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diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 87b7185..0a65191 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,296 +1,296 @@
# ---------------------------------
# - General Setup -
# ---------------------------------
stages:
- build
- test
- FOG:build
- FOG:test
- clean_code
- publish
variables:
# build directories
HEJ_BUILD_DIR: tmp_HEJ/HEJ_build
HEJ_INSTALL_DIR: tmp_HEJ/HEJ_installed
FOG_BUILD_DIR: tmp_HEJ/FOG_build
FOG_INSTALL_DIR: ${HEJ_INSTALL_DIR}
# docker images
DOCKER_BASIC: hejdock/hepenv
DOCKER_HEPMC3: hejdock/hepmc3env
DOCKER_QCDLOOP: hejdock/qcdloopenv
DOCKER_RIVET: hejdock/rivetenv
# ----------- Macros -----------
after_script:
- date
.tags_template:
tags: &tags_def
- docker
# save complete history of failed tests
.save_failure:
artifacts: &artifacts_failed
when: on_failure
untracked: true
expire_in: 3d
# ---------------------------------
# - Script Templates -
# ---------------------------------
# ----------- Build -----------
.HEJ_build:
tags: *tags_def
stage: build
before_script:
- date
- source /cvmfs/pheno.egi.eu/HEJ/HEJ_env.sh || exit 1
# prepare build
- t_HEJ_DIR=${PWD}
- t_HEJ_INSTALL_DIR=${PWD}/${HEJ_INSTALL_DIR}
- t_HEJ_BUILD_DIR=${PWD}/${HEJ_BUILD_DIR}
- mkdir -p ${t_HEJ_BUILD_DIR}
- cd ${t_HEJ_BUILD_DIR}
- cmake ${t_HEJ_DIR} -DCMAKE_BUILD_TYPE=DEBUG
-DCMAKE_INSTALL_PREFIX=${t_HEJ_INSTALL_DIR}
script:
- make -j $(nproc --ignore=1)
- make install
artifacts:
# save build and installed folder
name: build
expire_in: 1d
paths:
- ${HEJ_INSTALL_DIR}
- ${HEJ_BUILD_DIR}
# ----------- Test -----------
.HEJ_test:
tags: *tags_def
stage: test
before_script:
- date
- source /cvmfs/pheno.egi.eu/HEJ/HEJ_env.sh || exit 1
# load HEJ
- t_HEJ_DIR=${PWD}
- t_HEJ_INSTALL_DIR=${PWD}/${HEJ_INSTALL_DIR}
- export LD_LIBRARY_PATH=${t_HEJ_INSTALL_DIR}/lib:${LD_LIBRARY_PATH}
- export PATH=${t_HEJ_INSTALL_DIR}/bin:${PATH}
- cd ${HEJ_BUILD_DIR}
- cmake ${t_HEJ_DIR} # rerun cmake to create all test configure files
script:
- ctest --output-on-failure
artifacts: *artifacts_failed
## ----------- FOG build -----------
.FOG_build:
tags: *tags_def
stage: FOG:build
before_script:
- date
- source /cvmfs/pheno.egi.eu/HEJ/HEJ_env.sh || exit 1
# load HEJ
- t_HEJ_INSTALL_DIR=${PWD}/${HEJ_INSTALL_DIR}
- export LD_LIBRARY_PATH=${t_HEJ_INSTALL_DIR}/lib:${LD_LIBRARY_PATH}
- export PATH=${t_HEJ_INSTALL_DIR}/bin:${PATH}
# prepare build
- t_FOG_DIR=${PWD}/FixedOrderGen
- t_FOG_INSTALL_DIR=${PWD}/${FOG_INSTALL_DIR}
- t_FOG_BUILD_DIR=${PWD}/${FOG_BUILD_DIR}
- mkdir -p ${t_FOG_BUILD_DIR}
- cd ${t_FOG_BUILD_DIR}
- cmake ${t_FOG_DIR} -DCMAKE_BUILD_TYPE=DEBUG
-DCMAKE_INSTALL_PREFIX=${t_FOG_INSTALL_DIR}
script:
- make -j $(nproc --ignore=1)
- make install
artifacts:
# save build and installed folder
name: FOG_build
expire_in: 1d
paths:
- ${HEJ_INSTALL_DIR}
- ${FOG_INSTALL_DIR}
- ${FOG_BUILD_DIR}
## ----------- FOG test -----------
.FOG_test:
tags: *tags_def
stage: FOG:test
before_script:
- date
- source /cvmfs/pheno.egi.eu/HEJ/HEJ_env.sh || exit 1
# load HEJ
- t_FOG_DIR=${PWD}/FixedOrderGen
- t_HEJ_INSTALL_DIR=${PWD}/${HEJ_INSTALL_DIR}
- t_FOG_INSTALL_DIR=${PWD}/${FOG_INSTALL_DIR}
- export LD_LIBRARY_PATH=${t_HEJ_INSTALL_DIR}/lib:${LD_LIBRARY_PATH}
- export PATH=${t_HEJ_INSTALL_DIR}/bin:${t_FOG_INSTALL_DIR}/bin:${PATH}
- t_FOG_BUILD_DIR=${PWD}/${FOG_BUILD_DIR}
- cd ${t_FOG_BUILD_DIR}
- cmake ${t_FOG_DIR} # rerun cmake to create all test configure files
script:
- - make test
+ - ctest --output-on-failure
artifacts: *artifacts_failed
# ---------------------------------
# - Build & Test -
# ---------------------------------
# ----------- basic -----------
build:basic:
image: ${DOCKER_BASIC}
extends: .HEJ_build
test:basic:
image: ${DOCKER_BASIC}
extends: .HEJ_test
dependencies:
- build:basic
FOG:build:basic:
image: ${DOCKER_BASIC}
extends: .FOG_build
dependencies:
- build:basic
FOG:test:basic:
image: ${DOCKER_BASIC}
extends: .FOG_test
dependencies:
- FOG:build:basic
# ----------- HepMC 3 -----------
build:hepmc3:
image: ${DOCKER_HEPMC3}
extends: .HEJ_build
test:hepmc3:
image: ${DOCKER_HEPMC3}
extends: .HEJ_test
dependencies:
- build:hepmc3
# ----------- QCDloop -----------
build:qcdloop:
image: ${DOCKER_QCDLOOP}
extends: .HEJ_build
test:qcdloop:
image: ${DOCKER_QCDLOOP}
extends: .HEJ_test
dependencies:
- build:qcdloop
# ----------- rivet -----------
build:rivet:
image: ${DOCKER_RIVET}
extends: .HEJ_build
test:rivet:
image: ${DOCKER_RIVET}
extends: .HEJ_test
dependencies:
- build:rivet
script:
- ctest --output-on-failure
- bash -c '[ -f tst.yoda ]' && echo "found rivet output"
- rivet-cmphistos tst.yoda
- bash -c '[ -f MC_XS_XS.dat ]' && echo "yoda not empty"
# ---------------------------------
# - Clean Code -
# ---------------------------------
No_tabs:
stage: clean_code
tags: *tags_def
image: hejdock/git
dependencies: []
script:
- date
- check_tabs
# ----------- No gcc warnings -----------
.Warning_build:
extends: .HEJ_build
stage: clean_code
dependencies: []
script:
- cd ${t_HEJ_DIR}
# suppress warnings from side packages
- sed -i 's/include_directories(${LHAPDF/include_directories(SYSTEM ${LHAPDF/g' CMakeLists.txt
- sed -i 's/include_directories(${fastjet/include_directories(SYSTEM ${fastjet/g' CMakeLists.txt
- sed -i 's/include_directories(${Boost/include_directories(SYSTEM ${Boost/g' CMakeLists.txt
- cd ${t_HEJ_BUILD_DIR}
- cmake ${t_HEJ_DIR} -DCMAKE_CXX_FLAGS="-Werror"
- make -j $(nproc --ignore=1)
artifacts: # don't save anything
.Warning_FOG:
extends: .FOG_build
stage: clean_code
script:
- cd ${t_FOG_DIR}
# suppress warnings from side packages
- sed -i 's/include_directories(${LHAPDF/include_directories(SYSTEM ${LHAPDF/g' CMakeLists.txt
- sed -i 's/include_directories(${fastjet/include_directories(SYSTEM ${fastjet/g' CMakeLists.txt
- sed -i 's/include_directories(${Boost/include_directories(SYSTEM ${Boost/g' CMakeLists.txt
- cd ${t_FOG_BUILD_DIR}
- cmake ${t_FOG_DIR} -DCMAKE_CXX_FLAGS="-Werror"
- make -j $(nproc --ignore=1)
artifacts: # don't save anything
No_Warning:basic:
image: ${DOCKER_BASIC}
extends: .Warning_build
No_Warning:basic:FOG:
image: ${DOCKER_BASIC}
extends: .Warning_FOG
dependencies:
- build:basic
# ---------------------------------
# - Publish -
# ---------------------------------
Publish_version:
stage: publish
tags: *tags_def
image: hejdock/git
dependencies: []
only:
- /^v\d+\.\d+$/
except:
- tags
when: on_success
before_script:
- mkdir -p .ssh/ && echo "${SSH_KEY}" > .ssh/id_rsa && chmod 0600 .ssh/id_rsa
- rm -rf ~/.ssh/id_rsa; mkdir -p ~/.ssh/
- ln -s $PWD/.ssh/id_rsa ~/.ssh/id_rsa && chmod 0600 ~/.ssh/id_rsa
- ssh -T ${PUBLIC_GIT_PREFIX} -o "StrictHostKeyChecking no" || echo "added ssh"
script:
- git remote add public ${PUBLIC_GIT_PREFIX}${PUBLIC_GIT_POSTFIX}
- git checkout $CI_COMMIT_REF_NAME
- git branch
- git pull
- git push public
- git push public --tags
after_script:
- rm -f /root/.ssh/id_rsa && rm -fr .ssh
- git remote rm public
diff --git a/CMakeLists.txt b/CMakeLists.txt
index c48e69f..903f689 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,280 +1,292 @@
cmake_minimum_required(VERSION 3.1 FATAL_ERROR)
set(CMAKE_LEGACY_CYGWIN_WIN32 0)
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
-project("HEJ" VERSION 2.0.4 LANGUAGES C CXX)
+project("HEJ" VERSION 2.0.5 LANGUAGES C CXX)
# Set a default build type if none was specified
set(default_build_type "RelWithDebInfo")
if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
message(STATUS "Setting build type to '${default_build_type}' as none was specified.")
set(CMAKE_BUILD_TYPE "${default_build_type}" CACHE
STRING "Choose the type of build." FORCE)
# Set the possible values of build type for cmake-gui
set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS
"Debug" "Release" "MinSizeRel" "RelWithDebInfo")
endif()
## Flags for the compiler. No warning allowed.
if (CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_GNUCXX)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra")
elseif (MSVC)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /W4 /WX /EHsc")
endif()
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_STANDARD 14)
## Create Version
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/")
# Get the latest abbreviated commit hash of the working branch
execute_process(
COMMAND git rev-parse HEAD
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
OUTPUT_VARIABLE PROJECT_GIT_REVISION
OUTPUT_STRIP_TRAILING_WHITESPACE
)
# Get the current working branch
execute_process(
COMMAND git rev-parse --abbrev-ref HEAD
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
OUTPUT_VARIABLE PROJECT_GIT_BRANCH
OUTPUT_STRIP_TRAILING_WHITESPACE
)
## target directories for install
set(INSTALL_INCLUDE_DIR_BASE include)
set(INSTALL_INCLUDE_DIR ${INSTALL_INCLUDE_DIR_BASE}/HEJ)
set(INSTALL_BIN_DIR bin)
set(INSTALL_LIB_DIR lib)
set(INSTALL_CONFIG_DIR lib/cmake/HEJ)
## Template files
configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/cmake/Templates/Version.hh.in
${PROJECT_BINARY_DIR}/include/HEJ/Version.hh @ONLY )
configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/cmake/Templates/HEJ-config.cc.in
${PROJECT_BINARY_DIR}/src/bin/HEJ-config.cc @ONLY )
# Generate CMake config file
include(CMakePackageConfigHelpers)
configure_package_config_file(
cmake/Templates/hej-config.cmake.in
${CMAKE_CURRENT_BINARY_DIR}/${INSTALL_CONFIG_DIR}/hej-config.cmake
INSTALL_DESTINATION ${INSTALL_CONFIG_DIR}
PATH_VARS INSTALL_INCLUDE_DIR_BASE INSTALL_LIB_DIR
)
write_basic_package_version_file(
${CMAKE_CURRENT_BINARY_DIR}/${INSTALL_CONFIG_DIR}/hej-config-version.cmake
COMPATIBILITY SameMajorVersion
)
install(
FILES ${CMAKE_CURRENT_BINARY_DIR}/${INSTALL_CONFIG_DIR}/hej-config.cmake
${CMAKE_CURRENT_BINARY_DIR}/${INSTALL_CONFIG_DIR}/hej-config-version.cmake
DESTINATION ${INSTALL_CONFIG_DIR})
## Add directories and find dependences
include_directories(${CMAKE_CURRENT_SOURCE_DIR}/include ${PROJECT_BINARY_DIR}/include)
find_package(fastjet REQUIRED)
include_directories(${fastjet_INCLUDE_DIRS})
find_package(CLHEP 2.3 REQUIRED)
include_directories(${CLHEP_INCLUDE_DIRS})
find_package(LHAPDF REQUIRED)
include_directories(${LHAPDF_INCLUDE_DIRS})
## Amend unintuitive behaviour of FindBoost.cmake
## Priority of BOOST_ROOT over BOOSTROOT matches FindBoost.cmake
## at least for cmake 3.12
if(DEFINED BOOST_ROOT)
message("BOOST_ROOT set - only looking for Boost in ${BOOST_ROOT}")
set(Boost_NO_BOOST_CMAKE ON)
elseif(DEFINED BOOSTROOT)
message("BOOSTROOT set - only looking for Boost in ${BOOSTROOT}")
set(Boost_NO_BOOST_CMAKE ON)
endif()
find_package(Boost REQUIRED COMPONENTS iostreams)
include_directories(${Boost_INCLUDE_DIRS})
find_package(yaml-cpp) # requiring yaml does not work with fedora
include_directories(${YAML_CPP_INCLUDE_DIR})
if(${EXCLUDE_HepMC})
message(STATUS "Skipping HepMC")
# avoid "unused variable" warning if EXCLUDE_rivet is set by user
set(EXCLUDE_rivet TRUE)
else()
find_package(HepMC 2)
endif()
if(${HepMC_FOUND})
set(
CMAKE_CXX_FLAGS
"${CMAKE_CXX_FLAGS} -DHEJ_BUILD_WITH_HepMC_VERSION=${HepMC_VERSION_MAJOR}"
)
include_directories(${HepMC_INCLUDE_DIRS})
if(${EXCLUDE_rivet})
message(STATUS "Skipping rivet")
else()
find_package(rivet)
endif()
if(${rivet_FOUND})
include_directories(${rivet_INCLUDE_DIRS})
set(
CMAKE_CXX_FLAGS
"${CMAKE_CXX_FLAGS} -DHEJ_BUILD_WITH_RIVET"
)
endif()
endif()
if(${EXCLUDE_QCDloop})
message(STATUS "Skipping QCDloop")
else()
find_package(QCDloop 2)
endif()
if(${QCDloop_FOUND})
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DHEJ_BUILD_WITH_QCDLOOP")
include_directories(SYSTEM ${QCDloop_INCLUDE_DIRS})
endif()
add_subdirectory(src)
## define executable
add_executable(HEJ src/bin/HEJ.cc)
## link libraries
target_link_libraries(HEJ hejlib)
add_executable(HEJ-config src/bin/HEJ-config.cc)
file(GLOB hej_headers ${CMAKE_CURRENT_SOURCE_DIR}/include/HEJ/*.hh ${PROJECT_BINARY_DIR}/include/HEJ/*.hh)
file(GLOB lhef_headers ${CMAKE_CURRENT_SOURCE_DIR}/include/LHEF/*.h)
install(FILES ${hej_headers} DESTINATION ${INSTALL_INCLUDE_DIR})
install(FILES ${lhef_headers} DESTINATION include/LHEF/)
install(TARGETS HEJ HEJ-config DESTINATION ${INSTALL_BIN_DIR})
## tests
enable_testing()
set(tst_dir "${CMAKE_CURRENT_SOURCE_DIR}/t")
add_executable(test_classify ${tst_dir}/test_classify.cc)
add_executable(test_psp ${tst_dir}/test_psp.cc)
add_executable(test_ME_generic ${tst_dir}/test_ME_generic.cc)
add_executable(check_res ${tst_dir}/check_res.cc)
add_executable(check_lhe ${tst_dir}/check_lhe.cc)
add_library(scales SHARED ${tst_dir}/scales.cc)
add_executable(test_scale_import ${tst_dir}/test_scale_import)
add_executable(test_descriptions ${tst_dir}/test_descriptions)
add_executable(test_scale_arithmetics ${tst_dir}/test_scale_arithmetics)
+add_executable(test_parameters ${tst_dir}/test_parameters)
+add_executable(test_colours ${tst_dir}/test_colours)
target_link_libraries(test_classify hejlib)
target_link_libraries(test_psp hejlib)
target_link_libraries(test_ME_generic hejlib)
target_link_libraries(check_res hejlib)
target_link_libraries(check_lhe hejlib)
target_link_libraries(test_scale_import hejlib)
target_link_libraries(test_descriptions hejlib)
target_link_libraries(test_scale_arithmetics hejlib)
+target_link_libraries(test_parameters hejlib)
+target_link_libraries(test_colours hejlib)
## add tests
add_test(
NAME t_classify
COMMAND test_classify ${tst_dir}/classify.lhe.gz
)
add_test(
NAME t_psp
COMMAND test_psp ${tst_dir}/psp_gen.lhe.gz
)
set(tst_ME_data_dir "${tst_dir}/ME_data")
add_test(
NAME t_ME_j
COMMAND test_ME_generic ${tst_ME_data_dir}/config_mtinf.yml ${tst_ME_data_dir}/ME_jets_tree.dat ${tst_ME_data_dir}/PSP_jets.lhe.gz
)
add_test(
NAME t_ME_h
COMMAND test_ME_generic ${tst_ME_data_dir}/config_mtinf.yml ${tst_ME_data_dir}/ME_h_mtinf_tree.dat ${tst_ME_data_dir}/PSP_h.lhe.gz
)
# add_test(
# NAME t_ME_w
# COMMAND test_ME_generic ${tst_ME_data_dir}/config_w_ME.yml ${tst_ME_data_dir}/ME_w_tree.dat ${tst_ME_data_dir}/PSP_w.lhe.gz
# )
add_test(
NAME t_ME_w_FKL
COMMAND test_ME_generic ${tst_ME_data_dir}/config_w_ME.yml ${tst_ME_data_dir}/ME_w_FKL_tree.dat ${tst_ME_data_dir}/PSP_w_FKL.lhe.gz
)
add_test(
NAME t_ME_w_FKL_virt
COMMAND test_ME_generic ${tst_ME_data_dir}/config_w_ME.yml ${tst_ME_data_dir}/ME_w_FKL_virt.dat ${tst_ME_data_dir}/PSP_w_FKL.lhe.gz
)
if(${QCDloop_FOUND})
add_test(
NAME t_ME_h_mt
COMMAND test_ME_generic ${tst_ME_data_dir}/config_mt.yml ${tst_ME_data_dir}/ME_h_mt_tree.dat ${tst_ME_data_dir}/PSP_h.lhe.gz
)
add_test(
NAME t_ME_h_mtmb
COMMAND test_ME_generic ${tst_ME_data_dir}/config_mtmb.yml ${tst_ME_data_dir}/ME_h_mtmb_tree.dat ${tst_ME_data_dir}/PSP_h.lhe.gz
)
endif()
add_test(
NAME t_2j
COMMAND check_res ${tst_dir}/2j.lhe.gz 3.49391e+07 419684
)
add_test(
NAME t_3j
COMMAND check_res ${tst_dir}/3j.lhe.gz 2.37902e+06 25746.6
)
add_test(
NAME t_4j
COMMAND check_res ${tst_dir}/4j.lhe.gz 603713 72822.6
)
add_test(
NAME t_h_3j
COMMAND check_res ${tst_dir}/h_3j.lhe.gz 0.821622 0.0220334
)
add_test(
NAME t_h_3j_uno
COMMAND check_res ${tst_dir}/h_3j_uno.lhe.gz 0.0261968 0.000341549 uno
)
if(${HepMC_FOUND})
file(READ "${tst_dir}/jet_config.yml" config)
file(WRITE "${tst_dir}/jet_config_withHepMC.yml" "${config} - tst.hepmc")
if(${rivet_FOUND})
file(READ "${tst_dir}/jet_config_withHepMC.yml" config)
file(WRITE "${tst_dir}/jet_config_withRivet.yml" "${config}\n\nanalysis:\n rivet: MC_XS\n output: tst")
add_test(
NAME t_main
COMMAND HEJ ${tst_dir}/jet_config_withRivet.yml ${tst_dir}/2j.lhe.gz
)
else()
add_test(
NAME t_main
COMMAND HEJ ${tst_dir}/jet_config_withHepMC.yml ${tst_dir}/2j.lhe.gz
)
endif()
if(${HepMC_VERSION_MAJOR} GREATER 2)
add_executable(check_hepmc ${tst_dir}/check_hepmc.cc)
target_link_libraries(check_hepmc hejlib)
add_test(
NAME t_hepmc
COMMAND check_hepmc tst.hepmc
)
endif()
else()
add_test(
NAME t_main
COMMAND HEJ ${tst_dir}/jet_config.yml ${tst_dir}/2j.lhe.gz
)
endif()
add_test(
NAME t_lhe
COMMAND check_lhe tst.lhe
)
add_test(
NAME t_scale_import
COMMAND test_scale_import ${tst_dir}/jet_config_with_import.yml
)
add_test(
NAME t_descriptions
COMMAND test_descriptions
)
add_test(
NAME t_scale_arithmetics
COMMAND test_scale_arithmetics ${tst_dir}/jet_config.yml ${tst_dir}/2j.lhe.gz
)
+add_test(
+ NAME test_parameters
+ COMMAND test_parameters
+ )
+add_test(
+ NAME t_colour_flow
+ COMMAND test_colours
+ )
diff --git a/Changes-API.md b/Changes-API.md
new file mode 100644
index 0000000..f0a7cc8
--- /dev/null
+++ b/Changes-API.md
@@ -0,0 +1,53 @@
+# Changelog for HEJ API
+
+This log lists only changes on the HEJ API. These are primarily code changes
+relevant for calling HEJ as an API. This file should only be read as an addition
+to `Changes.md`, where the main features are documented.
+
+## Version 2.X
+
+### 2.X.0
+
+* Made `MatrixElement.tree_kin(...)` and `MatrixElement.tree_param(...)` public
+* New class `CrossSectionAccumulator` to keep track of Cross Section of the
+ different subproccess
+* New template struct `Parameters` similar to old `Weights`
+ - `Weights` are now an alias for `Parameters<double>`. Calling `Weights` did
+ not change
+ - `Weights.hh` was replaced by `Parameters.hh`. The old `Weights.hh` header
+ will be removed in HEJ Version 2.3.0
+* Function to multiplication and division of `EventParameters.weight` by double
+ - This can be combined with `Parameters`, e.g.
+ `Parameters<EventParameters>*Weights`, see also `Events.parameters()`
+ - Moved `EventParameters` to `Parameters.hh` header
+* Restructured `Event` class
+ - `Event` can now only be build from a (new) `Event::EventData` class
+ - Removed default constructor for `Event`
+ - `Event::EventData` replaces the old `UnclusteredEvent` struct.
+ - `UnclusteredEvent` is now deprecated, and will be removed in HEJ Version
+ 2.3.0
+ - Removed `Event.unclustered()` function
+ - Added new member function `Events.parameters()`, to directly access
+ (underlying) `Parameters<EventParameters>`
+
+## Version 2.0
+
+### 2.0.5
+
+* no further changes to API
+
+### 2.0.4
+
+* Fixed wrong path of `HEJ_INCLUDE_DIR` in `hej-config.cmake`
+
+### 2.0.3
+
+* no further changes to API
+
+### 2.0.2
+
+* no further changes to API
+
+### 2.0.1
+
+* no further changes to API
diff --git a/Changes.md b/Changes.md
index aea4b72..0d2386b 100644
--- a/Changes.md
+++ b/Changes.md
@@ -1,33 +1,61 @@
-# Version 2.0
+# Changelog
-## 2.X.0
+This is the log for changes to the HEJ program. Further changes to the HEJ API
+are documented in `Changes-API.md`. If you are using HEJ as a library, please
+also read the changes there.
+
+## Version 2.X
+
+### 2.X.0
-* Made `MatrixElement::tree_kin` and `MatrixElement::tree_param` public
* Allow multiplication and division of multiple scale functions e.g.
`H_T/2*m_j1j2`
+* Print cross sections at end of run
* Follow HepMC convention for particle Status codes: incoming = 11,
decaying = 2, outgoing = 1 (unchanged)
* New class `CrossSectionAccumulator` to keep track of Cross Section of the
different subproccess
-
-## 2.0.4
+* New template struct `Parameters` similar to old `Weights`
+ - `Weights` are now an alias for `Parameters<double>`. Calling `Weights` did
+ not change
+ - `Weights.hh` was replaced by `Parameters.hh`. The old `Weights.hh` header
+ will be removed in HEJ Version 2.3.0
+* Function to multiplication and division of `EventParameters.weight` by double
+ - This can be combined with `Parameters`, e.g.
+ `Parameters<EventParameters>*Weights`, see also `Events.parameters()`
+ - Moved `EventParameters` to `Parameters.hh` header
+* Restructured `Event` class
+ - `Event` can now only be build from a (new) `Event::EventData` class
+ - Removed default constructor for `Event`
+ - `Event::EventData` replaces the old `UnclusteredEvent` struct.
+ - `UnclusteredEvent` is now deprecated, and will be removed in HEJ Version
+ 2.3.0
+ - Removed `Event.unclustered()` function
+ - Added new member function `Events.parameters()`, to directly access
+ (underlying) `Parameters<EventParameters>`
+* Added optional Colour charges to particles (`Particle.colour`)
+ - Colours are read from and written to LHE files
+ - Colour connection in the HEJ limit can be generated via
+ `Event::generate_colours` (automatically done in the resummation)
+
+## 2.0.5
+
+* Fixed event classification for input not ordered in rapidity
+
+### 2.0.4
* Fixed wrong path of `HEJ_INCLUDE_DIR` in `hej-config.cmake`
-* Correctly include rivet headers
-* New `EXCLUDE_package` variable in `cmake` to not interface to specific
- packages
-* Consistent search and include for side packages in `cmake`
-## 2.0.3
+### 2.0.3
* Fixed parsing of (numerical factor) * (base scale) in configuration
* Don't change scale names, but sanitise Rivet output file names instead
-## 2.0.2
+### 2.0.2
* Changed scale names to `"_over_"` and `"_times_"` for proper file names (was
`"/"` and `"*"` before)
-## 2.0.1
+### 2.0.1
* Fixed name of fixed-order generator in error message.
diff --git a/FixedOrderGen/CMakeLists.txt b/FixedOrderGen/CMakeLists.txt
index bc4e530..ef16662 100644
--- a/FixedOrderGen/CMakeLists.txt
+++ b/FixedOrderGen/CMakeLists.txt
@@ -1,113 +1,113 @@
cmake_minimum_required(VERSION 3.1 FATAL_ERROR)
set(CMAKE_LEGACY_CYGWIN_WIN32 0)
set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
-project("HEJ Fixed Order Generation" VERSION 2.0.4 LANGUAGES C CXX)
+project("HEJ Fixed Order Generation" VERSION 2.0.5 LANGUAGES C CXX)
# Set a default build type if none was specified
set(default_build_type "RelWithDebInfo")
if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
message(STATUS "Setting build type to '${default_build_type}' as none was specified.")
set(CMAKE_BUILD_TYPE "${default_build_type}" CACHE
STRING "Choose the type of build." FORCE)
# Set the possible values of build type for cmake-gui
set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS
"Debug" "Release" "MinSizeRel" "RelWithDebInfo")
endif()
## Flags for the compiler. No warning allowed.
if (CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_GNUCXX)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra")
elseif (MSVC)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /W4 /WX /EHsc")
endif()
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_STANDARD 14)
## Create Version
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/")
# Get the latest abbreviated commit hash of the working branch
execute_process(
COMMAND git rev-parse HEAD
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
OUTPUT_VARIABLE PROJECT_GIT_REVISION
OUTPUT_STRIP_TRAILING_WHITESPACE
)
# Get the current working branch
execute_process(
COMMAND git rev-parse --abbrev-ref HEAD
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
OUTPUT_VARIABLE PROJECT_GIT_BRANCH
OUTPUT_STRIP_TRAILING_WHITESPACE
)
CONFIGURE_FILE( ${CMAKE_CURRENT_SOURCE_DIR}/cmake/Templates/Version.hh.in
${PROJECT_BINARY_DIR}/include/Version.hh @ONLY )
## Add directories and find dependences
include_directories(${CMAKE_CURRENT_SOURCE_DIR}/include ${PROJECT_BINARY_DIR}/include)
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/../cmake/Modules/")
find_package(HEJ 2 REQUIRED)
include_directories(${HEJ_INCLUDE_DIR})
find_package(fastjet REQUIRED)
include_directories(${fastjet_INCLUDE_DIRS})
find_package(CLHEP 2.3 REQUIRED)
include_directories(${CLHEP_INCLUDE_DIRS})
find_package(LHAPDF REQUIRED)
include_directories(${LHAPDF_INCLUDE_DIRS})
## Amend unintuitive behaviour of FindBoost.cmake
## Priority of BOOST_ROOT over BOOSTROOT matches FindBoost.cmake
## at least for cmake 3.12
if(DEFINED BOOST_ROOT)
message("BOOST_ROOT set - only looking for Boost in ${BOOST_ROOT}")
set(Boost_NO_BOOST_CMAKE ON)
elseif(DEFINED BOOSTROOT)
message("BOOSTROOT set - only looking for Boost in ${BOOSTROOT}")
set(Boost_NO_BOOST_CMAKE ON)
endif()
find_package(Boost REQUIRED COMPONENTS iostreams)
include_directories(${Boost_INCLUDE_DIRS})
find_package(yaml-cpp) # requiring yaml does not work with fedora
include_directories(${YAML_CPP_INCLUDE_DIR})
## define executable
file(GLOB HEJFOG_source ${CMAKE_CURRENT_SOURCE_DIR}/src/*.cc)
list(REMOVE_ITEM HEJFOG_source ${CMAKE_CURRENT_SOURCE_DIR}/src/main.cc)
add_library(hejfog STATIC ${HEJFOG_source})
add_executable(HEJFOG ${CMAKE_CURRENT_SOURCE_DIR}/src/main.cc)
## link libraries
set(libraries ${CMAKE_DL_LIBS} ${LHAPDF_LIBRARIES} ${CLHEP_LIBRARIES}
${fastjet_LIBRARIES} ${Boost_LIBRARIES} ${YAML_CPP_LIBRARIES} ${HEJ_LIBRARIES})
target_link_libraries(hejfog ${libraries})
target_link_libraries(HEJFOG hejfog)
install(TARGETS HEJFOG DESTINATION bin)
## tests
enable_testing()
set(tst_dir "${CMAKE_CURRENT_SOURCE_DIR}/t")
foreach(tst h_2j h_3j h_5j h_3j_uno1 h_3j_uno2 h_2j_decay 2j 4j W_2j_classify W_nj_classify)
add_executable(test_${tst} ${tst_dir}/${tst}.cc)
target_link_libraries(test_${tst} hejfog)
add_test(NAME t_${tst} COMMAND test_${tst} WORKING_DIRECTORY ${tst_dir})
endforeach()
add_test(
NAME t_main_2j
COMMAND HEJFOG ${tst_dir}/config_2j.yml
)
add_test(
NAME t_main_h2j
COMMAND HEJFOG ${tst_dir}/config_h_2j.yml
)
add_test(
NAME t_main_h2j_decay
COMMAND HEJFOG ${tst_dir}/config_h_2j_decay.yml
)
diff --git a/FixedOrderGen/include/EventGenerator.hh b/FixedOrderGen/include/EventGenerator.hh
index a039144..e2064c7 100644
--- a/FixedOrderGen/include/EventGenerator.hh
+++ b/FixedOrderGen/include/EventGenerator.hh
@@ -1,56 +1,57 @@
#pragma once
-#include "HEJ/PDF.hh"
#include "HEJ/MatrixElement.hh"
+#include "HEJ/optional.hh"
+#include "HEJ/PDF.hh"
#include "HEJ/RNG.hh"
+#include "Beam.hh"
#include "JetParameters.hh"
+#include "ParticleProperties.hh"
#include "Process.hh"
-#include "Beam.hh"
#include "Status.hh"
-#include "ParticleProperties.hh"
namespace HEJ{
class Event;
class HiggsCouplingSettings;
class ScaleGenerator;
}
//! Namespace for HEJ Fixed Order Generator
namespace HEJFOG{
class EventGenerator{
public:
EventGenerator(
Process process,
Beam beam,
HEJ::ScaleGenerator scale_gen,
JetParameters jets,
int pdf_id,
double subl_change,
unsigned int subl_channels,
ParticlesPropMap particles_properties,
HEJ::HiggsCouplingSettings Higgs_coupling,
HEJ::RNG & ran
);
- HEJ::Event gen_event();
+ HEJ::optional<HEJ::Event> gen_event();
Status status() const {
return status_;
}
private:
HEJ::PDF pdf_;
HEJ::MatrixElement ME_;
HEJ::ScaleGenerator scale_gen_;
Process process_;
JetParameters jets_;
Beam beam_;
Status status_;
double subl_change_;
unsigned int subl_channels_;
ParticlesPropMap particles_properties_;
std::reference_wrapper<HEJ::RNG> ran_;
};
}
diff --git a/FixedOrderGen/include/PhaseSpacePoint.hh b/FixedOrderGen/include/PhaseSpacePoint.hh
index 164c7ae..d2234b4 100644
--- a/FixedOrderGen/include/PhaseSpacePoint.hh
+++ b/FixedOrderGen/include/PhaseSpacePoint.hh
@@ -1,216 +1,216 @@
/** \file PhaseSpacePoint.hh
* \brief Contains the PhaseSpacePoint Class
*/
#pragma once
#include <bitset>
#include <vector>
#include "HEJ/Event.hh"
#include "HEJ/Particle.hh"
#include "HEJ/PDF.hh"
#include "HEJ/PDG_codes.hh"
#include "HEJ/RNG.hh"
#include "JetParameters.hh"
#include "ParticleProperties.hh"
#include "Status.hh"
namespace HEJFOG{
class Process;
using HEJ::Particle;
//! A point in resummation phase space
class PhaseSpacePoint{
public:
//! Default PhaseSpacePoint Constructor
PhaseSpacePoint() = default;
//! PhaseSpacePoint Constructor
/**
* @param proc The process to generate
* @param jet_properties Jet defintion & cuts
* @param pdf The pdf set (used for sampling)
* @param E_beam Energie of the beam
* @param subl_chance Chance to turn a potentially unordered
* emission into an actual one
* @param subl_channels Possible subleading channels.
* see HEJFOG::Subleading
* @param particle_properties Properties of producted boson
*
* Initially, only FKL phase space points are generated. subl_chance gives
* the change of turning one emissions into a subleading configuration,
* i.e. either unordered or central quark/anti-quark pair. Unordered
* emissions require that the most extremal emission in any direction is
* a quark or anti-quark and the next emission is a gluon. Quark/anti-quark
* pairs are only generated for W processes. At most one subleading
* emission will be generated in this way.
*/
PhaseSpacePoint(
Process const & proc,
JetParameters const & jet_properties,
HEJ::PDF & pdf, double E_beam,
double subl_chance,
unsigned int subl_channels,
ParticlesPropMap const & particles_properties,
HEJ::RNG & ran
);
//! Get Weight Function
/**
* @returns Weight of Event
*/
double weight() const{
return weight_;
}
Status status() const{
return status_;
}
//! Get Incoming Function
/**
* @returns Incoming Particles
*/
std::array<Particle, 2> const & incoming() const{
return incoming_;
}
//! Get Outgoing Function
/**
* @returns Outgoing Particles
*/
std::vector<Particle> const & outgoing() const{
return outgoing_;
}
std::unordered_map<size_t, std::vector<Particle>> const & decays() const{
return decays_;
}
private:
/**
* @internal
* @brief Generate LO parton momentum
*
* @param count Number of partons to generate
* @param is_pure_jets If true ensures momentum conservation in x and y
* @param jet_param Jet properties to fulfil
* @param max_pt max allowed pt for a parton (typically E_CMS)
* @param ran Random Number Generator
*
* @returns Momentum of partons
*
* Ensures that each parton is in its own jet.
* Generation is independent of parton flavour. Output is sorted in rapidity.
*/
std::vector<fastjet::PseudoJet> gen_LO_partons(
int count, bool is_pure_jets,
JetParameters const & jet_param,
double max_pt,
HEJ::RNG & ran
);
Particle gen_boson(
HEJ::ParticleID bosonid, double mass, double width,
HEJ::RNG & ran
);
template<class ParticleMomenta>
fastjet::PseudoJet gen_last_momentum(
ParticleMomenta const & other_momenta,
double mass_square, double y
) const;
bool jets_ok(
std::vector<fastjet::PseudoJet> const & Born_jets,
std::vector<fastjet::PseudoJet> const & partons
) const;
/**
* @internal
* @brief Generate incoming partons according to the PDF
*
* @param uf Scale used in the PDF
*/
void reconstruct_incoming(
Process const & proc, unsigned int subl_channels,
HEJ::PDF & pdf, double E_beam,
double uf,
HEJ::RNG & ran
);
/**
* @internal
* @brief Returns list of all allowed initial states partons
*/
std::array<std::bitset<11>,2> filter_partons(
Process const & proc, unsigned int const subl_channels,
HEJ::RNG & ran
);
HEJ::ParticleID generate_incoming_id(
size_t beam_idx, double x, double uf, HEJ::PDF & pdf,
std::bitset<11> allowed_partons, HEJ::RNG & ran
);
bool momentum_conserved(double ep) const;
HEJ::Particle const & most_backward_FKL(
std::vector<HEJ::Particle> const & partons
) const;
HEJ::Particle const & most_forward_FKL(
std::vector<HEJ::Particle> const & partons
) const;
HEJ::Particle & most_backward_FKL(std::vector<HEJ::Particle> & partons) const;
HEJ::Particle & most_forward_FKL(std::vector<HEJ::Particle> & partons) const;
bool extremal_FKL_ok(
std::vector<fastjet::PseudoJet> const & partons
) const;
double random_normal(double stddev, HEJ::RNG & ran);
/**
* @internal
* @brief Turns a FKL configuration into a subleading one
*
* @param chance Change to switch to subleading configuration
* @param channels Allowed channels for subleading process
* @param proc Process to decide which subleading
* configurations are allowed
*
* With a chance of "chance" the FKL configuration is either turned into
* a unordered configuration or, for A/W/Z bosons, a configuration with
* a central quark/anti-quark pair.
*/
void maybe_turn_to_subl(double chance, unsigned int channels,
Process const & proc, HEJ::RNG & ran);
void turn_to_uno(bool can_be_uno_backward, bool can_be_uno_forward, HEJ::RNG & ran);
void turn_to_qqx(bool allow_strange, HEJ::RNG & ran);
std::vector<Particle> decay_boson(
HEJ::Particle const & parent,
std::vector<Decay> const & decays,
HEJ::RNG & ran
);
/// @brief setup outgoing partons to ensure correct coupling to boson
void couple_boson(HEJ::ParticleID boson, HEJ::RNG & ran);
Decay select_decay_channel(
std::vector<Decay> const & decays,
HEJ::RNG & ran
);
double gen_hard_pt(
int np, double ptmin, double ptmax, double y,
HEJ::RNG & ran
);
double gen_soft_pt(int np, double ptmax, HEJ::RNG & ran);
double gen_parton_pt(
int count, JetParameters const & jet_param, double ptmax, double y,
HEJ::RNG & ran
);
double weight_;
Status status_;
std::array<Particle, 2> incoming_;
std::vector<Particle> outgoing_;
//! Particle decays in the format {outgoing index, decay products}
std::unordered_map<size_t, std::vector<Particle>> decays_;
};
- HEJ::UnclusteredEvent to_UnclusteredEvent(PhaseSpacePoint const & psp);
+ HEJ::Event::EventData to_EventData(PhaseSpacePoint const & psp);
}
diff --git a/FixedOrderGen/src/EventGenerator.cc b/FixedOrderGen/src/EventGenerator.cc
index eb99958..c97839a 100644
--- a/FixedOrderGen/src/EventGenerator.cc
+++ b/FixedOrderGen/src/EventGenerator.cc
@@ -1,80 +1,80 @@
#include "EventGenerator.hh"
#include "Process.hh"
#include "Beam.hh"
#include "JetParameters.hh"
#include "PhaseSpacePoint.hh"
#include "HEJ/Event.hh"
#include "HEJ/config.hh"
namespace HEJFOG{
EventGenerator::EventGenerator(
Process process,
Beam beam,
HEJ::ScaleGenerator scale_gen,
JetParameters jets,
int pdf_id,
double subl_change,
unsigned int subl_channels,
ParticlesPropMap particles_properties,
HEJ::HiggsCouplingSettings Higgs_coupling,
HEJ::RNG & ran
):
pdf_{pdf_id, beam.particles[0], beam.particles[1]},
ME_{
[this](double mu){ return pdf_.Halphas(mu); },
HEJ::MatrixElementConfig{
false,
std::move(Higgs_coupling)
}
},
scale_gen_{std::move(scale_gen)},
process_{std::move(process)},
jets_{std::move(jets)},
beam_{std::move(beam)},
subl_change_{subl_change},
subl_channels_{subl_channels},
particles_properties_{std::move(particles_properties)},
ran_{ran}
{
}
- HEJ::Event EventGenerator::gen_event(){
+ HEJ::optional<HEJ::Event> EventGenerator::gen_event(){
HEJFOG::PhaseSpacePoint psp{
process_,
jets_,
pdf_, beam_.energy,
subl_change_, subl_channels_,
particles_properties_,
ran_
};
status_ = psp.status();
if(status_ != good) return {};
HEJ::Event ev = scale_gen_(
HEJ::Event{
- to_UnclusteredEvent(std::move(psp)),
- jets_.def, jets_.min_pt
+ to_EventData( std::move(psp) ).cluster( jets_.def, jets_.min_pt)
}
);
+ ev.generate_colours(ran_);
+
const double shat = HEJ::shat(ev);
const double xa = (ev.incoming()[0].E()-ev.incoming()[0].pz())/(2.*beam_.energy);
const double xb = (ev.incoming()[1].E()+ev.incoming()[1].pz())/(2.*beam_.energy);
- // evaluate matrix element on this point
- const auto ME_weights = ME_.tree(ev);
- ev.central().weight *= ME_weights.central/(shat*shat);
+ // evaluate matrix element
+ ev.parameters() *= ME_.tree(ev)/(shat*shat);
+ // and PDFs
ev.central().weight *= pdf_.pdfpt(0,xa,ev.central().muf, ev.incoming()[0].type);
ev.central().weight *= pdf_.pdfpt(0,xb,ev.central().muf, ev.incoming()[1].type);
for(size_t i = 0; i < ev.variations().size(); ++i){
auto & var = ev.variations(i);
- var.weight *= ME_weights.variations[i]/(shat*shat);
var.weight *= pdf_.pdfpt(0,xa,var.muf, ev.incoming()[0].type);
var.weight *= pdf_.pdfpt(0,xb,var.muf, ev.incoming()[1].type);
}
return ev;
}
}
diff --git a/FixedOrderGen/src/PhaseSpacePoint.cc b/FixedOrderGen/src/PhaseSpacePoint.cc
index 8969c40..ed36539 100644
--- a/FixedOrderGen/src/PhaseSpacePoint.cc
+++ b/FixedOrderGen/src/PhaseSpacePoint.cc
@@ -1,665 +1,662 @@
#include "PhaseSpacePoint.hh"
#include <random>
#include <algorithm>
#include "HEJ/Constants.hh"
#include <CLHEP/Random/Randomize.h>
#include <CLHEP/Random/RanluxEngine.h>
#include "HEJ/exceptions.hh"
#include "HEJ/kinematics.hh"
#include "HEJ/Particle.hh"
#include "HEJ/utility.hh"
#include "Process.hh"
#include "Subleading.hh"
using namespace HEJ;
namespace HEJFOG{
static_assert(
std::numeric_limits<double>::has_quiet_NaN,
"no quiet NaN for double"
);
constexpr double NaN = std::numeric_limits<double>::quiet_NaN();
- HEJ::UnclusteredEvent to_UnclusteredEvent(PhaseSpacePoint const & psp){
- HEJ::UnclusteredEvent result;
+
+ HEJ::Event::EventData to_EventData(PhaseSpacePoint const & psp){
+ HEJ::Event::EventData result;
result.incoming = psp.incoming();
- std::sort(
- begin(result.incoming), end(result.incoming),
- [](Particle o1, Particle o2){return o1.p.pz()<o2.p.pz();}
- );
assert(result.incoming.size() == 2);
- result.outgoing = psp.outgoing();
+ result.outgoing=psp.outgoing();
+ // technically Event::EventData doesn't have to be sorted,
+ // but PhaseSpacePoint should be anyway
assert(
std::is_sorted(
begin(result.outgoing), end(result.outgoing),
HEJ::rapidity_less{}
)
);
assert(result.outgoing.size() >= 2);
- result.decays = psp.decays();
- result.central.mur = NaN;
- result.central.muf = NaN;
- result.central.weight = psp.weight();
+ result.decays=psp.decays();
+ result.parameters.central= {NaN, NaN, psp.weight() };
return result;
}
namespace{
bool can_swap_to_uno(
HEJ::Particle const & p1, HEJ::Particle const & p2
){
return is_parton(p1)
&& p1.type != pid::gluon
&& p2.type == pid::gluon;
}
size_t count_gluons(std::vector<Particle>::const_iterator first,
std::vector<Particle>::const_iterator last){
return std::count_if(first, last, [](Particle const & p)
{return p.type == pid::gluon;});
}
/** assumes FKL configurations between first and last,
* else there can be a quark in a non-extreme position
* e.g. uno configuration gqg would pass
*/
bool can_change_to_qqx(
std::vector<Particle>::const_iterator first,
std::vector<Particle>::const_iterator last){
return 1 < count_gluons(first,last);
}
bool is_AWZ_proccess(Process const & proc){
return proc.boson && is_AWZ_boson(*proc.boson);
}
bool is_up_type(Particle const & part){
return HEJ::is_anyquark(part) && !(abs(part.type)%2);
}
bool is_down_type(Particle const & part){
return HEJ::is_anyquark(part) && abs(part.type)%2;
}
/// true iff parton can couple to a W
bool can_couple_to_W(Particle const & part, int const sign_W){
return abs(part.type)<5
&& ( (sign_W*part.type > 0 && is_up_type(part))
|| (sign_W*part.type < 0 && is_down_type(part)) );
}
}
void PhaseSpacePoint::maybe_turn_to_subl(
double chance,
unsigned int const channels,
Process const & proc,
HEJ::RNG & ran
){
if(proc.njets <= 2) return;
assert(outgoing_.size() >= 2);
// decide what kind of subleading process is allowed
bool allow_uno = false;
bool allow_strange = true;
const size_t nout = outgoing_.size();
const bool can_be_uno_backward = (channels&Subleading::uno)
&& can_swap_to_uno(outgoing_[0], outgoing_[1]);
const bool can_be_uno_forward = (channels&Subleading::uno)
&& can_swap_to_uno(outgoing_[nout-1], outgoing_[nout-2]);
allow_uno = can_be_uno_backward || can_be_uno_forward;
bool allow_qqx = false;
if(is_AWZ_proccess(proc)) {
allow_qqx = (channels&Subleading::qqx)
&& can_change_to_qqx(outgoing_.cbegin(), outgoing_.cend());
const int sign_W = *proc.boson>0?1:-1;
if(std::none_of(outgoing_.cbegin(), outgoing_.cend(),
[sign_W](Particle const & p){ return can_couple_to_W(p, sign_W);})) {
// enforce qqx if A/W/Z can't couple somewhere else
assert(allow_qqx);
allow_uno = false;
chance = 1.;
// strange not allowed for W
if(abs(*proc.boson)== pid::Wp) allow_strange = false;
}
}
if(!allow_uno && !allow_qqx) return;
if(ran.flat() < chance){
weight_ /= chance;
if(allow_uno && !allow_qqx){
turn_to_uno(can_be_uno_backward, can_be_uno_forward, ran);
} else if (!allow_uno && allow_qqx) {
turn_to_qqx(allow_strange, ran);
} else {
assert( allow_uno && allow_qqx);
if(ran.flat() < 0.5) turn_to_uno(can_be_uno_backward, can_be_uno_forward, ran);
else turn_to_qqx(allow_strange, ran);
weight_ *= 2.;
}
} else weight_ /= 1 - chance;
}
void PhaseSpacePoint::turn_to_uno(
const bool can_be_uno_backward, const bool can_be_uno_forward,
HEJ::RNG & ran
){
if(!can_be_uno_backward && !can_be_uno_forward) return;
const size_t nout = outgoing_.size();
if(can_be_uno_backward && can_be_uno_forward){
if(ran.flat() < 0.5){
std::swap(outgoing_[0].type, outgoing_[1].type);
} else {
std::swap(outgoing_[nout-1].type, outgoing_[nout-2].type);
}
weight_ *= 2.;
} else if(can_be_uno_backward){
std::swap(outgoing_[0].type, outgoing_[1].type);
} else {
assert(can_be_uno_forward);
std::swap(outgoing_[nout-1].type, outgoing_[nout-2].type);
}
}
void PhaseSpacePoint::turn_to_qqx(const bool allow_stange, HEJ::RNG & ran){
/// find first and last gluon in FKL chain
auto first = std::find_if(outgoing_.begin(), outgoing_.end(),
[](Particle const & p){return p.type == pid::gluon;});
std::vector<Particle*> FKL_gluons;
for(auto p = first; p<outgoing_.end(); ++p){
if((*p).type == pid::gluon) FKL_gluons.push_back(&*p);
else if(is_quark(*p) || is_antiquark(*p)) break;
}
const size_t ng = FKL_gluons.size();
if(ng < 2)
throw std::logic_error("not enough gluons to create qqx");
// select flavour of quark
const double r1 = 2.*ran.flat()-1.;
const double max_flavour = allow_stange?n_f:n_f-1;
weight_ *= max_flavour*2;
int flavour = pid::down;
for (double sum = 1./max_flavour; sum < std::abs(r1); sum += 1./max_flavour)
++flavour;
flavour*=r1<0.?-1:1;
// select gluon for switch
const size_t idx = floor((ng-1) * ran.flat());
weight_ *= (ng-1);
FKL_gluons[idx]->type = ParticleID(flavour);
FKL_gluons[idx+1]->type = ParticleID(-flavour);
}
template<class ParticleMomenta>
fastjet::PseudoJet PhaseSpacePoint::gen_last_momentum(
ParticleMomenta const & other_momenta,
const double mass_square, const double y
) const {
std::array<double,2> pt{0.,0.};
for (auto const & p: other_momenta) {
pt[0]-= p.px();
pt[1]-= p.py();
}
const double mperp = sqrt(pt[0]*pt[0]+pt[1]*pt[1]+mass_square);
const double pz=mperp*sinh(y);
const double E=mperp*cosh(y);
return {pt[0], pt[1], pz, E};
}
PhaseSpacePoint::PhaseSpacePoint(
Process const & proc,
JetParameters const & jet_param,
HEJ::PDF & pdf, double E_beam,
double const subl_chance,
unsigned int const subl_channels,
ParticlesPropMap const & particles_properties,
HEJ::RNG & ran
)
{
assert(proc.njets >= 2);
if(proc.boson
&& particles_properties.find(*(proc.boson))
== particles_properties.end())
throw HEJ::missing_option("Boson "
+std::to_string(*(proc.boson))+" can't be generated: missing properties");
status_ = good;
weight_ = 1;
const int nout = proc.njets + (proc.boson?1:0);
outgoing_.reserve(nout);
// generate parton momenta
const bool is_pure_jets = !proc.boson;
auto partons = gen_LO_partons(
proc.njets, is_pure_jets, jet_param, E_beam, ran
);
// pre fill flavour with gluons
for(auto&& p_out: partons) {
- outgoing_.emplace_back(Particle{pid::gluon, std::move(p_out)});
+ outgoing_.emplace_back(Particle{pid::gluon, std::move(p_out), {}});
}
if(status_ != good) return;
// create boson
if(proc.boson){
const auto & boson_prop = particles_properties.at(*proc.boson);
auto boson(gen_boson(*proc.boson, boson_prop.mass, boson_prop.width, ran));
const auto pos = std::upper_bound(
begin(outgoing_),end(outgoing_),boson,rapidity_less{}
);
outgoing_.insert(pos, std::move(boson));
if(! boson_prop.decays.empty()){
const size_t boson_idx = std::distance(begin(outgoing_), pos);
decays_.emplace(
boson_idx,
decay_boson(outgoing_[boson_idx], boson_prop.decays, ran)
);
}
}
// normalisation of momentum-conserving delta function
weight_ *= pow(2*M_PI, 4);
reconstruct_incoming(proc, subl_channels, pdf,E_beam,jet_param.min_pt, ran);
if(status_ != good) return;
// set outgoing states
most_backward_FKL(outgoing_).type = incoming_[0].type;
most_forward_FKL(outgoing_).type = incoming_[1].type;
maybe_turn_to_subl(subl_chance, subl_channels, proc, ran);
if(proc.boson) couple_boson(*proc.boson, ran);
}
double PhaseSpacePoint::gen_hard_pt(
int np , double ptmin, double ptmax, double y,
HEJ::RNG & ran
) {
// heuristic parameters for pt sampling
const double ptpar = ptmin + np/5.;
const double arg_small_y = atan((ptmax - ptmin)/ptpar);
const double y_cut = 3.;
const double r1 = ran.flat();
if(y < y_cut){
const double pt = ptmin + ptpar*tan(r1*arg_small_y);
const double temp = cos(r1*arg_small_y);
weight_ *= pt*ptpar*arg_small_y/(temp*temp);
return pt;
}
const double ptpar2 = ptpar/(1 + 5*(y-y_cut));
const double temp = 1. - std::exp((ptmin-ptmax)/ptpar2);
const double pt = ptmin - ptpar2*std::log(1-r1*temp);
weight_ *= pt*ptpar2*temp/(1-r1*temp);
return pt;
}
double PhaseSpacePoint::gen_soft_pt(int np, double max_pt, HEJ::RNG & ran) {
constexpr double ptpar = 4.;
const double r = ran.flat();
const double pt = max_pt + ptpar/np*std::log(r);
weight_ *= pt*ptpar/(np*r);
return pt;
}
double PhaseSpacePoint::gen_parton_pt(
int count, JetParameters const & jet_param, double max_pt, double y,
HEJ::RNG & ran
) {
constexpr double p_small_pt = 0.02;
if(! jet_param.peak_pt) {
return gen_hard_pt(count, jet_param.min_pt, max_pt, y, ran);
}
const double r = ran.flat();
if(r > p_small_pt) {
weight_ /= 1. - p_small_pt;
return gen_hard_pt(count, *jet_param.peak_pt, max_pt, y, ran);
}
weight_ /= p_small_pt;
const double pt = gen_soft_pt(count, *jet_param.peak_pt, ran);
if(pt < jet_param.min_pt) {
weight_=0.0;
status_ = not_enough_jets;
return jet_param.min_pt;
}
return pt;
}
std::vector<fastjet::PseudoJet> PhaseSpacePoint::gen_LO_partons(
int np, bool is_pure_jets,
JetParameters const & jet_param,
double max_pt,
HEJ::RNG & ran
){
if (np<2) throw std::invalid_argument{"Not enough partons in gen_LO_partons"};
weight_ /= pow(16.*pow(M_PI,3),np);
weight_ /= std::tgamma(np+1); //remove rapidity ordering
std::vector<fastjet::PseudoJet> partons;
partons.reserve(np);
for(int i = 0; i < np; ++i){
const double y = -jet_param.max_y + 2*jet_param.max_y*ran.flat();
weight_ *= 2*jet_param.max_y;
const bool is_last_parton = i+1 == np;
if(is_pure_jets && is_last_parton) {
constexpr double parton_mass_sq = 0.;
partons.emplace_back(gen_last_momentum(partons, parton_mass_sq, y));
break;
}
const double phi = 2*M_PI*ran.flat();
weight_ *= 2.0*M_PI;
const double pt = gen_parton_pt(np, jet_param, max_pt, y, ran);
if(weight_ == 0.0) return {};
partons.emplace_back(fastjet::PtYPhiM(pt, y, phi));
assert(jet_param.min_pt <= partons[i].pt());
assert(partons[i].pt() <= max_pt+1e-5);
}
// Need to check that at LO, the number of jets = number of partons;
fastjet::ClusterSequence cs(partons, jet_param.def);
auto cluster_jets=cs.inclusive_jets(jet_param.min_pt);
if (cluster_jets.size()!=unsigned(np)){
weight_=0.0;
status_ = not_enough_jets;
return {};
}
std::sort(begin(partons), end(partons), rapidity_less{});
return partons;
}
Particle PhaseSpacePoint::gen_boson(
HEJ::ParticleID bosonid, double mass, double width,
HEJ::RNG & ran
){
// Usual phase space measure
weight_ /= 16.*pow(M_PI, 3);
// Generate a y Gaussian distributed around 0
/// @TODO: magic number only for Higgs
/// @TODO better sampling for W
const double y = random_normal(1.6, ran);
const double r1 = ran.flat();
const double sH = mass*(
mass + width*tan(M_PI/2.*r1 + (r1-1.)*atan(mass/width))
);
auto p = gen_last_momentum(outgoing_, sH, y);
- return Particle{bosonid, std::move(p)};
+ return Particle{bosonid, std::move(p), {}};
}
Particle const & PhaseSpacePoint::most_backward_FKL(
std::vector<Particle> const & partons
) const{
if(!HEJ::is_parton(partons[0])) return partons[1];
return partons[0];
}
Particle const & PhaseSpacePoint::most_forward_FKL(
std::vector<Particle> const & partons
) const{
const size_t last_idx = partons.size() - 1;
if(!HEJ::is_parton(partons[last_idx])) return partons[last_idx-1];
return partons[last_idx];
}
Particle & PhaseSpacePoint::most_backward_FKL(
std::vector<Particle> & partons
) const{
if(!HEJ::is_parton(partons[0])) return partons[1];
return partons[0];
}
Particle & PhaseSpacePoint::most_forward_FKL(
std::vector<Particle> & partons
) const{
const size_t last_idx = partons.size() - 1;
if(!HEJ::is_parton(partons[last_idx])) return partons[last_idx-1];
return partons[last_idx];
}
namespace {
/// partons are ordered: even = anti, 0 = gluon
ParticleID index_to_pid(size_t i){
if(!i) return pid::gluon;
return static_cast<ParticleID>(i%2?(i+1)/2:-i/2);
}
/// partons are ordered: even = anti, 0 = gluon
size_t pid_to_index(ParticleID id){
if(id==pid::gluon) return 0;
return id>0?id*2-1:abs(id)*2;
}
std::bitset<11> init_allowed(ParticleID const id){
if(abs(id) == pid::proton)
return ~0;
std::bitset<11> out = 0;
if(is_parton(id))
out[pid_to_index(id)] = 1;
return out;
}
/// decides which "index" (see index_to_pid) are allowed for process
std::bitset<11> allowed_quarks(ParticleID const boson){
std::bitset<11> allowed = ~0;
if(abs(boson) == pid::Wp){
// special case W:
// Wp: anti-down or up-type quark, no b/t -> 0001100110(1) = 205
// Wm: down or anti-up-type quark, no b/t -> 0010011001(1) = 307
allowed = boson>0?205:307;
}
return allowed;
}
}
/**
* checks which partons are allowed as initial state:
* 1. only allow what is given in the Runcard (p -> all)
* 2. A/W/Z require something to couple to
* a) no qqx => no incoming gluon
* b) 2j => no incoming gluon
* c) 3j => can couple OR is gluon => 2 gluons become qqx later
*/
std::array<std::bitset<11>,2> PhaseSpacePoint::filter_partons(
Process const & proc, unsigned int const subl_channels, HEJ::RNG & ran
){
std::array<std::bitset<11>,2> allowed_partons{
init_allowed(proc.incoming[0]),
init_allowed(proc.incoming[1])
};
bool const allow_qqx = subl_channels&Subleading::qqx;
// special case A/W/Z
if(is_AWZ_proccess(proc) && ((proc.njets < 4) || !allow_qqx)){
// all possible incoming states
auto allowed(allowed_quarks(*proc.boson));
if(proc.njets == 2 || !allow_qqx) allowed[0]=0;
// possible states per leg
std::array<std::bitset<11>,2> const maybe_partons{
allowed_partons[0]&allowed, allowed_partons[1]&allowed};
if(maybe_partons[0].any() && maybe_partons[1].any()){
// two options to get allowed initial state => choose one at random
const size_t idx = ran.flat() < 0.5;
allowed_partons[idx] = maybe_partons[idx];
// else choose the possible
} else if(maybe_partons[0].any()) {
allowed_partons[0] = maybe_partons[0];
} else if(maybe_partons[1].any()) {
allowed_partons[1] = maybe_partons[1];
} else{
throw std::invalid_argument{"Incoming state not allowed."};
}
}
return allowed_partons;
}
void PhaseSpacePoint::reconstruct_incoming(
Process const & proc, unsigned int const subl_channels,
HEJ::PDF & pdf, double E_beam,
double uf,
HEJ::RNG & ran
){
std::tie(incoming_[0].p, incoming_[1].p) = incoming_momenta(outgoing_);
// calculate xa, xb
const double sqrts=2*E_beam;
const double xa=(incoming_[0].p.e()-incoming_[0].p.pz())/sqrts;
const double xb=(incoming_[1].p.e()+incoming_[1].p.pz())/sqrts;
// abort if phase space point is outside of collider energy reach
if (xa>1. || xb>1.){
weight_=0;
status_ = too_much_energy;
return;
}
// pick pdfs
/** @TODO
* ufa, ufb don't correspond to our final scale choice.
* The HEJ scale generators currently expect a full event as input,
* so fixing this is not completely trivial
*/
auto const & ids = proc.incoming;
std::array<std::bitset<11>,2> allowed_partons(
filter_partons(proc, subl_channels, ran));
for(size_t i = 0; i < 2; ++i){
if(ids[i] == pid::proton || ids[i] == pid::p_bar){
incoming_[i].type =
generate_incoming_id(i, i?xb:xa, uf, pdf, allowed_partons[i], ran);
} else {
assert(allowed_partons[i][pid_to_index(ids[i])]);
incoming_[i].type = ids[i];
}
}
assert(momentum_conserved(1e-7));
}
HEJ::ParticleID PhaseSpacePoint::generate_incoming_id(
size_t const beam_idx, double const x, double const uf,
HEJ::PDF & pdf, std::bitset<11> allowed_partons, HEJ::RNG & ran
){
std::array<double,11> pdf_wt;
pdf_wt[0] = allowed_partons[0]?fabs(pdf.pdfpt(beam_idx,x,uf,pid::gluon)):0.;
double pdftot = pdf_wt[0];
for(size_t i = 1; i < pdf_wt.size(); ++i){
pdf_wt[i] = allowed_partons[i]?4./9.*fabs(pdf.pdfpt(beam_idx,x,uf,index_to_pid(i))):0;
pdftot += pdf_wt[i];
}
const double r1 = pdftot * ran.flat();
double sum = 0;
for(size_t i=0; i < pdf_wt.size(); ++i){
if (r1 < (sum+=pdf_wt[i])){
weight_*= pdftot/pdf_wt[i];
return index_to_pid(i);
}
}
std::cerr << "Error in choosing incoming parton: "<<x<<" "<<uf<<" "
<<sum<<" "<<pdftot<<" "<<r1<<std::endl;
throw std::logic_error{"Failed to choose parton flavour"};
}
void PhaseSpacePoint::couple_boson(
HEJ::ParticleID const boson, HEJ::RNG & ran
){
if(abs(boson) != pid::Wp) return; // only matters for W
/// @TODO this could be use to sanity check gamma and Z
// find all possible quarks
const int sign_W = boson>0?1:-1;
std::vector<Particle*> allowed_parts;
for(auto & part: outgoing_){
// Wp -> up OR anti-down, Wm -> anti-up OR down, no bottom
if ( can_couple_to_W(part, sign_W) )
allowed_parts.push_back(&part);
}
if(allowed_parts.size() == 0){
throw std::logic_error{"Found no parton for coupling with boson"};
}
// select one and flip it
size_t idx = 0;
if(allowed_parts.size() > 1){
/// @TODO more efficient sampling
/// old code: probability[i] = exp(parton[i].y - W.y)
idx = floor(ran.flat()*allowed_parts.size());
weight_ *= allowed_parts.size();
}
allowed_parts[idx]->type =
static_cast<ParticleID>( allowed_parts[idx]->type - sign_W );
}
double PhaseSpacePoint::random_normal(
double stddev,
HEJ::RNG & ran
){
const double r1 = ran.flat();
const double r2 = ran.flat();
const double lninvr1 = -log(r1);
const double result = stddev*sqrt(2.*lninvr1)*cos(2.*M_PI*r2);
weight_ *= exp(result*result/(2*stddev*stddev))*sqrt(2.*M_PI)*stddev;
return result;
}
bool PhaseSpacePoint::momentum_conserved(double ep) const{
fastjet::PseudoJet diff;
for(auto const & in: incoming()) diff += in.p;
for(auto const & out: outgoing()) diff -= out.p;
return nearby_ep(diff, fastjet::PseudoJet{}, ep);
}
Decay PhaseSpacePoint::select_decay_channel(
std::vector<Decay> const & decays,
HEJ::RNG & ran
){
double br_total = 0.;
for(auto const & decay: decays) br_total += decay.branching_ratio;
// adjust weight
// this is given by (channel branching ratio)/(chance to pick channel)
// where (chance to pick channel) =
// (channel branching ratio)/(total branching ratio)
weight_ *= br_total;
const double r1 = br_total*ran.flat();
double br_sum = 0.;
for(auto const & decay: decays){
br_sum += decay.branching_ratio;
if(r1 < br_sum) return decay;
}
throw std::logic_error{"unreachable"};
}
std::vector<Particle> PhaseSpacePoint::decay_boson(
HEJ::Particle const & parent,
std::vector<Decay> const & decays,
HEJ::RNG & ran
){
const auto channel = select_decay_channel(decays, ran);
if(channel.products.size() != 2){
throw HEJ::not_implemented{
"only decays into two particles are implemented"
};
}
std::vector<Particle> decay_products(channel.products.size());
for(size_t i = 0; i < channel.products.size(); ++i){
decay_products[i].type = channel.products[i];
}
// choose polar and azimuth angle in parent rest frame
const double E = parent.m()/2;
const double theta = 2.*M_PI*ran.flat();
const double cos_phi = 2.*ran.flat()-1.;
const double sin_phi = sqrt(1. - cos_phi*cos_phi); // Know 0 < phi < pi
const double px = E*cos(theta)*sin_phi;
const double py = E*sin(theta)*sin_phi;
const double pz = E*cos_phi;
decay_products[0].p.reset(px, py, pz, E);
decay_products[1].p.reset(-px, -py, -pz, E);
for(auto & particle: decay_products) particle.p.boost(parent.p);
return decay_products;
}
}
diff --git a/FixedOrderGen/src/Unweighter.cc b/FixedOrderGen/src/Unweighter.cc
index 0ac4d74..7bb1695 100644
--- a/FixedOrderGen/src/Unweighter.cc
+++ b/FixedOrderGen/src/Unweighter.cc
@@ -1,34 +1,26 @@
#include "Unweighter.hh"
#include <cassert>
#include "HEJ/Event.hh"
namespace HEJFOG {
namespace detail {
bool has_jet_softer_than(HEJ::Event const & ev, double pt) {
assert(! ev.jets().empty());
const auto softest_jet = fastjet::sorted_by_pt(ev.jets()).back();
return softest_jet.pt() < pt;
}
}
- namespace {
- void normalise_weights(HEJ::Event & ev, double target) {
- const double awt = std::abs(ev.central().weight);
- ev.central().weight *= target/awt;
- for(auto & var: ev.variations()) var.weight *= target/awt;
- }
- }
-
HEJ::optional<HEJ::Event> Unweighter::unweight(HEJ::Event ev) const {
if(detail::has_jet_softer_than(ev, min_unweight_pt_)) return ev;
const double awt = std::abs(ev.central().weight);
if(ran_.get().flat() < awt/cut_) {
- if(awt < cut_) normalise_weights(ev, cut_);
+ if(awt < cut_) ev.parameters() *= cut_/awt;
return ev;
}
return {};
}
}
diff --git a/FixedOrderGen/src/main.cc b/FixedOrderGen/src/main.cc
index 6d55edb..01b9b80 100644
--- a/FixedOrderGen/src/main.cc
+++ b/FixedOrderGen/src/main.cc
@@ -1,233 +1,228 @@
/**
* Name: main.cc
* Authors: Jeppe R. Andersen
*/
#include <algorithm>
#include <chrono>
#include <fstream>
#include <iostream>
#include <map>
#include <memory>
#include "yaml-cpp/yaml.h"
#include "LHEF/LHEF.h"
#include "HEJ/CombinedEventWriter.hh"
#include "HEJ/CrossSectionAccumulator.hh"
#include "HEJ/get_analysis.hh"
#include "HEJ/LesHouchesWriter.hh"
#include "HEJ/make_RNG.hh"
#include "HEJ/ProgressBar.hh"
#include "HEJ/stream.hh"
#include "config.hh"
#include "EventGenerator.hh"
#include "PhaseSpacePoint.hh"
#include "Unweighter.hh"
#include "Version.hh"
namespace{
constexpr auto banner =
" __ ___ __ ______ __ __ \n"
" / / / (_)___ _/ /_ / ____/___ ___ _________ ___ __ / /__ / /______ \n"
" / /_/ / / __ `/ __ \\ / __/ / __ \\/ _ \\/ ___/ __ `/ / / / __ / / _ \\/ __/ ___/ \n"
" / __ / / /_/ / / / / / /___/ / / / __/ / / /_/ / /_/ / / /_/ / __/ /_(__ ) \n"
" /_/ /_/_/\\__, /_/ /_/ /_____/_/ /_/\\___/_/ \\__, /\\__, / \\____/\\___/\\__/____/ \n"
" ____///__/ __ ____ ///__//____/ ______ __ \n"
" / ____(_) _____ ____/ / / __ \\_________/ /__ _____ / ____/__ ____ ___ _________ _/ /_____ _____\n"
" / /_ / / |/_/ _ \\/ __ / / / / / ___/ __ / _ \\/ ___/ / / __/ _ \\/ __ \\/ _ \\/ ___/ __ `/ __/ __ \\/ ___/\n"
" / __/ / /> </ __/ /_/ / / /_/ / / / /_/ / __/ / / /_/ / __/ / / / __/ / / /_/ / /_/ /_/ / / \n"
" /_/ /_/_/|_|\\___/\\__,_/ \\____/_/ \\__,_/\\___/_/ \\____/\\___/_/ /_/\\___/_/ \\__,_/\\__/\\____/_/ \n"
;
constexpr double invGeV2_to_pb = 389379292.;
constexpr long long max_warmup_events = 10000;
}
HEJFOG::Config load_config(char const * filename){
try{
return HEJFOG::load_config(filename);
}
catch(std::exception const & exc){
std::cerr << "Error: " << exc.what() << '\n';
std::exit(EXIT_FAILURE);
}
}
std::unique_ptr<HEJ::Analysis> get_analysis(
YAML::Node const & parameters
){
try{
return HEJ::get_analysis(parameters);
}
catch(std::exception const & exc){
std::cerr << "Failed to load analysis: " << exc.what() << '\n';
std::exit(EXIT_FAILURE);
}
}
-void rescale_weights(HEJ::Event & ev, double factor) {
- ev.central().weight *= factor;
- for(auto & var: ev.variations()){
- var.weight *= factor;
- }
-}
-
int main(int argn, char** argv) {
using namespace std::string_literals;
if (argn < 2) {
std::cerr << "\n# Usage:\n." << argv[0] << " config_file\n";
return EXIT_FAILURE;
}
std::cout << banner;
std::cout << "Version " << HEJFOG::Version::String()
<< ", revision " << HEJFOG::Version::revision() << std::endl;
fastjet::ClusterSequence::print_banner();
using clock = std::chrono::system_clock;
const auto start_time = clock::now();
// read configuration
auto config = load_config(argv[1]);
std::unique_ptr<HEJ::Analysis> analysis = get_analysis(
config.analysis_parameters
);
assert(analysis != nullptr);
auto ran = HEJ::make_RNG(config.rng.name, config.rng.seed);
assert(ran != nullptr);
HEJ::ScaleGenerator scale_gen{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
std::move(scale_gen),
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
*ran
};
LHEF::HEPRUP heprup;
heprup.IDBMUP=std::pair<long,long>(config.beam.particles[0], config.beam.particles[1]);
heprup.EBMUP=std::make_pair(config.beam.energy, config.beam.energy);
heprup.PDFGUP=std::make_pair(0,0);
heprup.PDFSUP=std::make_pair(config.pdf_id,config.pdf_id);
heprup.NPRUP=1;
heprup.XSECUP=std::vector<double>(1.);
heprup.XERRUP=std::vector<double>(1.);
heprup.LPRUP=std::vector<int>{1};
heprup.generators.emplace_back(LHEF::XMLTag{});
heprup.generators.back().name = HEJFOG::Version::package_name();
heprup.generators.back().version = HEJFOG::Version::String();
HEJ::CombinedEventWriter writer{config.output, heprup};
HEJ::optional<HEJFOG::Unweighter> unweighter{};
std::map<HEJFOG::Status, int> status_counter;
std::vector<HEJ::Event> events;
int trials = 0;
// warm-up phase to train unweighter
if(config.unweight) {
std::cout << "Calibrating unweighting ...\n";
const auto warmup_start = clock::now();
const size_t warmup_events = config.unweight->sample_size;
HEJ::ProgressBar<size_t> warmup_progress{std::cout, warmup_events};
for(; events.size() < warmup_events; ++trials){
auto ev = generator.gen_event();
++status_counter[generator.status()];
- if(generator.status() == HEJFOG::good && analysis->pass_cuts(ev, ev)) {
- events.emplace_back(std::move(ev));
+ assert( (generator.status() == HEJFOG::good) == bool(ev) );
+ if(generator.status() == HEJFOG::good && analysis->pass_cuts(*ev, *ev)) {
+ events.emplace_back(std::move(*ev));
++warmup_progress;
}
}
std::cout << std::endl;
unweighter = HEJFOG::Unweighter{
begin(events), end(events), config.unweight->max_dev, *ran,
config.jets.peak_pt?(*config.jets.peak_pt):0.
};
std::vector<HEJ::Event> unweighted_events;
for(auto && ev: events) {
auto unweighted = unweighter->unweight(std::move(ev));
if(unweighted) {
unweighted_events.emplace_back(std::move(*unweighted));
}
}
events = std::move(unweighted_events);
if(events.empty()) {
std::cerr <<
"Failed to generate events. Please increase \"unweight: sample size\""
" or reduce \"unweight: max deviation\"\n";
return EXIT_FAILURE;
}
const auto warmup_end = clock::now();
const double completion = static_cast<double>(events.size())/config.events;
const std::chrono::duration<double> remaining_time =
(warmup_end- warmup_start)*(1./completion - 1);
const auto finish = clock::to_time_t(
std::chrono::time_point_cast<std::chrono::seconds>(warmup_end + remaining_time)
);
std::cout
<< "Generated " << events.size() << "/" << config.events << " events ("
<< static_cast<int>(std::round(100*completion)) << "%)\n"
<< "Estimated remaining generation time: "
<< remaining_time.count() << " seconds ("
<< std::put_time(std::localtime(&finish), "%c") << ")\n\n";
}
HEJ::ProgressBar<long long> progress{std::cout, config.events};
progress.increment(events.size());
events.reserve(config.events);
for(; events.size() < static_cast<size_t>(config.events); ++trials){
auto ev = generator.gen_event();
++status_counter[generator.status()];
- if(generator.status() == HEJFOG::good && analysis->pass_cuts(ev, ev)) {
+ assert( (generator.status() == HEJFOG::good) == bool(ev) );
+ if(generator.status() == HEJFOG::good && analysis->pass_cuts(*ev, *ev)) {
if(unweighter) {
- auto unweighted = unweighter->unweight(std::move(ev));
+ auto unweighted = unweighter->unweight(std::move(*ev));
if(! unweighted) continue;
- ev = std::move(*unweighted);
+ ev = std::move(unweighted);
}
- events.emplace_back(std::move(ev));
+ events.emplace_back(std::move(*ev));
++progress;
}
}
std::cout << std::endl;
HEJ::CrossSectionAccumulator xs;
for(auto & ev: events){
- rescale_weights(ev, invGeV2_to_pb/trials);
+ ev.parameters() *= invGeV2_to_pb/trials;
analysis->fill(ev, ev);
writer.write(ev);
xs.fill(ev);
}
analysis->finalise();
const std::chrono::duration<double> run_time = (clock::now() - start_time);
std::cout << "\nTask Runtime: " << run_time.count() << " seconds.\n\n";
std::cout << xs << '\n';
for(auto && entry: status_counter){
const double fraction = static_cast<double>(entry.second)/trials;
const int percent = std::round(100*fraction);
std::cout << "status "
<< std::left << std::setw(16) << (to_string(entry.first) + ":")
<< " [";
for(int i = 0; i < percent/2; ++i) std::cout << '#';
for(int i = percent/2; i < 50; ++i) std::cout << ' ';
std::cout << "] " << percent << "%\n";
}
}
diff --git a/FixedOrderGen/t/2j.cc b/FixedOrderGen/t/2j.cc
index 80bdff3..ea68d04 100644
--- a/FixedOrderGen/t/2j.cc
+++ b/FixedOrderGen/t/2j.cc
@@ -1,59 +1,60 @@
#ifdef NDEBUG
#undef NDEBUG
#endif
#include <algorithm>
#include <cmath>
#include <cassert>
#include <iostream>
#include "config.hh"
#include "EventGenerator.hh"
#include "HEJ/Mixmax.hh"
#include "HEJ/Event.hh"
#include "HEJ/PDF.hh"
#include "HEJ/MatrixElement.hh"
using namespace HEJFOG;
int main(){
constexpr double invGeV2_to_pb = 389379292.;
constexpr double xs_ref = 86.42031848*1e6; //calculated with "combined" HEJ svn r3480
auto config = load_config("config_2j.yml");
HEJ::Mixmax ran{};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
HEJ::ScaleGenerator{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
},
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
ran
};
double xs = 0., xs_err = 0.;
for (int trials = 0; trials < config.events; ++trials){
auto ev = generator.gen_event();
if(generator.status() != good) continue;
- ev.central().weight *= invGeV2_to_pb;
- ev.central().weight /= config.events;
+ assert(ev);
+ ev->central().weight *= invGeV2_to_pb;
+ ev->central().weight /= config.events;
- xs += ev.central().weight;
- xs_err += ev.central().weight*ev.central().weight;
+ xs += ev->central().weight;
+ xs_err += ev->central().weight*ev->central().weight;
}
xs_err = std::sqrt(xs_err);
std::cout << xs_ref << " ~ " << xs << " +- " << xs_err << '\n';
assert(std::abs(xs - xs_ref) < 3*xs_err);
assert(xs_err < 0.01*xs);
}
diff --git a/FixedOrderGen/t/4j.cc b/FixedOrderGen/t/4j.cc
index 5b4e1b4..a597242 100644
--- a/FixedOrderGen/t/4j.cc
+++ b/FixedOrderGen/t/4j.cc
@@ -1,60 +1,61 @@
#ifdef NDEBUG
#undef NDEBUG
#endif
#include <algorithm>
#include <cmath>
#include <cassert>
#include <iostream>
#include "config.hh"
#include "EventGenerator.hh"
#include "HEJ/Mixmax.hh"
#include "HEJ/Event.hh"
#include "HEJ/PDF.hh"
#include "HEJ/MatrixElement.hh"
using namespace HEJFOG;
int main(){
constexpr double invGeV2_to_pb = 389379292.;
constexpr double xs_ref = 0.81063619*1e6; //calculated with "combined" HEJ svn r3480
auto config = load_config("config_2j.yml");
config.process.njets = 4;
HEJ::Mixmax ran{};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
HEJ::ScaleGenerator{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
},
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
ran
};
double xs = 0., xs_err = 0.;
for (int trials = 0; trials < config.events; ++trials){
auto ev = generator.gen_event();
if(generator.status() != good) continue;
- ev.central().weight *= invGeV2_to_pb;
- ev.central().weight /= config.events;
+ assert(ev);
+ ev->central().weight *= invGeV2_to_pb;
+ ev->central().weight /= config.events;
- xs += ev.central().weight;
- xs_err += ev.central().weight*ev.central().weight;
+ xs += ev->central().weight;
+ xs_err += ev->central().weight*ev->central().weight;
}
xs_err = std::sqrt(xs_err);
std::cout << xs_ref << " ~ " << xs << " +- " << xs_err << '\n';
assert(std::abs(xs - xs_ref) < 3*xs_err);
assert(xs_err < 0.03*xs);
}
diff --git a/FixedOrderGen/t/h_2j.cc b/FixedOrderGen/t/h_2j.cc
index 3e3135e..4ad315d 100644
--- a/FixedOrderGen/t/h_2j.cc
+++ b/FixedOrderGen/t/h_2j.cc
@@ -1,67 +1,68 @@
#ifdef NDEBUG
#undef NDEBUG
#endif
#include <algorithm>
#include <cmath>
#include <cassert>
#include <iostream>
#include "config.hh"
#include "EventGenerator.hh"
#include "HEJ/Ranlux64.hh"
#include "HEJ/Event.hh"
#include "HEJ/PDF.hh"
#include "HEJ/MatrixElement.hh"
using namespace HEJFOG;
int main(){
constexpr double invGeV2_to_pb = 389379292.;
constexpr double xs_ref = 2.04928; // +- 0.00377252
//calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
auto config = load_config("config_h_2j.yml");
HEJ::Ranlux64 ran{};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
HEJ::ScaleGenerator{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
},
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
ran
};
double xs = 0., xs_err = 0.;
for (int trials = 0; trials < config.events; ++trials){
auto ev = generator.gen_event();
if(generator.status() != good) continue;
- ev.central().weight *= invGeV2_to_pb;
- ev.central().weight /= config.events;
+ assert(ev);
+ ev->central().weight *= invGeV2_to_pb;
+ ev->central().weight /= config.events;
const auto the_Higgs = std::find_if(
- begin(ev.outgoing()), end(ev.outgoing()),
+ begin(ev->outgoing()), end(ev->outgoing()),
[](HEJ::Particle const & p){ return p.type == HEJ::ParticleID::h; }
);
- assert(the_Higgs != end(ev.outgoing()));
+ assert(the_Higgs != end(ev->outgoing()));
if(std::abs(the_Higgs->rapidity()) > 5.) continue;
- xs += ev.central().weight;
- xs_err += ev.central().weight*ev.central().weight;
+ xs += ev->central().weight;
+ xs_err += ev->central().weight*ev->central().weight;
}
xs_err = std::sqrt(xs_err);
std::cout << xs_ref << " ~ " << xs << " +- " << xs_err << std::endl;
assert(std::abs(xs - xs_ref) < 3*xs_err);
assert(xs_err < 0.01*xs);
}
diff --git a/FixedOrderGen/t/h_2j_decay.cc b/FixedOrderGen/t/h_2j_decay.cc
index 8454b7b..e404707 100644
--- a/FixedOrderGen/t/h_2j_decay.cc
+++ b/FixedOrderGen/t/h_2j_decay.cc
@@ -1,86 +1,87 @@
#ifdef NDEBUG
#undef NDEBUG
#endif
#include <algorithm>
#include <cmath>
#include <cassert>
#include <iostream>
#include "config.hh"
#include "EventGenerator.hh"
#include "HEJ/Event.hh"
#include "HEJ/MatrixElement.hh"
#include "HEJ/Particle.hh"
#include "HEJ/PDF.hh"
#include "HEJ/Ranlux64.hh"
#include "HEJ/utility.hh"
using namespace HEJFOG;
bool pass_dR_cut(
std::vector<fastjet::PseudoJet> const & jets,
std::vector<HEJ::Particle> const & photons
){
constexpr double delta_R_min = 0.7;
for(auto const & jet: jets){
for(auto const & photon: photons){
if(jet.delta_R(photon.p) < delta_R_min) return false;
}
}
return true;
}
int main(){
constexpr double invGeV2_to_pb = 389379292.;
constexpr double xs_ref = 0.00429198; // +- 1.0488e-05
//calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
auto config = load_config("config_h_2j_decay.yml");
HEJ::Ranlux64 ran{};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
HEJ::ScaleGenerator{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
},
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
ran
};
double xs = 0., xs_err = 0.;
for (int trials = 0; trials < config.events; ++trials){
auto ev = generator.gen_event();
if(generator.status() != good) continue;
- assert(ev.decays().size() == 1);
- const auto decay = begin(ev.decays());
- assert(ev.outgoing().size() > decay->first);
- const auto & the_Higgs = ev.outgoing()[decay->first];
+ assert(ev);
+ assert(ev->decays().size() == 1);
+ const auto decay = begin(ev->decays());
+ assert(ev->outgoing().size() > decay->first);
+ const auto & the_Higgs = ev->outgoing()[decay->first];
assert(the_Higgs.type == HEJ::pid::Higgs);
assert(decay->second.size() == 2);
auto const & gamma = decay->second;
assert(gamma[0].type == HEJ::pid::photon);
assert(gamma[1].type == HEJ::pid::photon);
assert(HEJ::nearby_ep(gamma[0].p + gamma[1].p, the_Higgs.p, 1e-6));
- if(!pass_dR_cut(ev.jets(), gamma)) continue;
- ev.central().weight *= invGeV2_to_pb;
- ev.central().weight /= config.events;
+ if(!pass_dR_cut(ev->jets(), gamma)) continue;
+ ev->central().weight *= invGeV2_to_pb;
+ ev->central().weight /= config.events;
- xs += ev.central().weight;
- xs_err += ev.central().weight*ev.central().weight;
+ xs += ev->central().weight;
+ xs_err += ev->central().weight*ev->central().weight;
}
xs_err = std::sqrt(xs_err);
std::cout << xs_ref << " ~ " << xs << " +- " << xs_err << std::endl;
assert(std::abs(xs - xs_ref) < 3*xs_err);
assert(xs_err < 0.012*xs);
}
diff --git a/FixedOrderGen/t/h_3j.cc b/FixedOrderGen/t/h_3j.cc
index cad089a..bb2baff 100644
--- a/FixedOrderGen/t/h_3j.cc
+++ b/FixedOrderGen/t/h_3j.cc
@@ -1,68 +1,69 @@
#ifdef NDEBUG
#undef NDEBUG
#endif
#include <algorithm>
#include <cmath>
#include <cassert>
#include <iostream>
#include "config.hh"
#include "EventGenerator.hh"
#include "HEJ/Ranlux64.hh"
#include "HEJ/Event.hh"
#include "HEJ/MatrixElement.hh"
#include "HEJ/PDF.hh"
using namespace HEJFOG;
int main(){
constexpr double invGeV2_to_pb = 389379292.;
constexpr double xs_ref = 1.07807; // +- 0.0071
//calculated with HEJ revision 93efdc851b02a907a6fcc63956387f9f4c1111c2 +1
auto config = load_config("config_h_2j.yml");
config.process.njets = 3;
HEJ::Ranlux64 ran{};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
HEJ::ScaleGenerator{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
},
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
ran
};
double xs = 0., xs_err = 0.;
for (int trials = 0; trials < config.events; ++trials){
auto ev = generator.gen_event();
if(generator.status() != good) continue;
- ev.central().weight *= invGeV2_to_pb;
- ev.central().weight /= config.events;
+ assert(ev);
+ ev->central().weight *= invGeV2_to_pb;
+ ev->central().weight /= config.events;
const auto the_Higgs = std::find_if(
- begin(ev.outgoing()), end(ev.outgoing()),
+ begin(ev->outgoing()), end(ev->outgoing()),
[](HEJ::Particle const & p){ return p.type == HEJ::ParticleID::h; }
);
- assert(the_Higgs != end(ev.outgoing()));
+ assert(the_Higgs != end(ev->outgoing()));
if(std::abs(the_Higgs->rapidity()) > 5.) continue;
- xs += ev.central().weight;
- xs_err += ev.central().weight*ev.central().weight;
+ xs += ev->central().weight;
+ xs_err += ev->central().weight*ev->central().weight;
}
xs_err = std::sqrt(xs_err);
std::cout << xs_ref << " ~ " << xs << " +- " << xs_err << std::endl;
assert(std::abs(xs - xs_ref) < 3*xs_err);
assert(xs_err < 0.02*xs);
}
diff --git a/FixedOrderGen/t/h_3j_uno1.cc b/FixedOrderGen/t/h_3j_uno1.cc
index 4c0f6f3..c100dcb 100644
--- a/FixedOrderGen/t/h_3j_uno1.cc
+++ b/FixedOrderGen/t/h_3j_uno1.cc
@@ -1,72 +1,73 @@
#ifdef NDEBUG
#undef NDEBUG
#endif
// check that adding uno emissions doesn't change the FKL cross section
#include <algorithm>
#include <cassert>
#include <cmath>
#include <iostream>
#include "config.hh"
#include "EventGenerator.hh"
#include "HEJ/Ranlux64.hh"
#include "Subleading.hh"
#include "HEJ/Event.hh"
#include "HEJ/MatrixElement.hh"
#include "HEJ/PDF.hh"
using namespace HEJFOG;
int main(){
constexpr double invGeV2_to_pb = 389379292.;
constexpr double xs_ref = 0.0243548; // +- 0.000119862
//calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
auto config = load_config("config_h_2j.yml");
config.process.njets = 3;
config.process.incoming = {HEJ::pid::u, HEJ::pid::u};
config.subleading_channels = HEJFOG::Subleading::uno;
HEJ::Ranlux64 ran{};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
HEJ::ScaleGenerator{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
},
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
ran
};
double xs = 0., xs_err = 0.;
int uno_found = 0;
for (int trials = 0; trials < config.events; ++trials){
auto ev = generator.gen_event();
if(generator.status() != good) continue;
- if(ev.type() != HEJ::event_type::FKL){
+ assert(ev);
+ if(ev->type() != HEJ::event_type::FKL){
++uno_found;
continue;
}
- ev.central().weight *= invGeV2_to_pb;
- ev.central().weight /= config.events;
+ ev->central().weight *= invGeV2_to_pb;
+ ev->central().weight /= config.events;
- xs += ev.central().weight;
- xs_err += ev.central().weight*ev.central().weight;
+ xs += ev->central().weight;
+ xs_err += ev->central().weight*ev->central().weight;
}
xs_err = std::sqrt(xs_err);
std::cout << xs_ref << " ~ " << xs << " +- " << xs_err << '\n';
std::cout << uno_found << " events with unordered emission" << std::endl;
assert(uno_found > 0);
assert(std::abs(xs - xs_ref) < 3*xs_err);
assert(xs_err < 0.05*xs);
}
diff --git a/FixedOrderGen/t/h_3j_uno2.cc b/FixedOrderGen/t/h_3j_uno2.cc
index 5c6c409..4dc4770 100644
--- a/FixedOrderGen/t/h_3j_uno2.cc
+++ b/FixedOrderGen/t/h_3j_uno2.cc
@@ -1,67 +1,68 @@
#ifdef NDEBUG
#undef NDEBUG
#endif
// check uno cross section
#include <algorithm>
#include <cassert>
#include <cmath>
#include <iostream>
#include "config.hh"
#include "EventGenerator.hh"
#include "HEJ/Ranlux64.hh"
#include "Subleading.hh"
#include "HEJ/Event.hh"
#include "HEJ/MatrixElement.hh"
#include "HEJ/PDF.hh"
using namespace HEJFOG;
int main(){
constexpr double invGeV2_to_pb = 389379292.;
constexpr double xs_ref = 0.00347538; // +- 3.85875e-05
//calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
auto config = load_config("config_h_2j.yml");
config.process.njets = 3;
config.process.incoming = {HEJ::pid::u, HEJ::pid::u};
config.subleading_fraction = 1.;
config.subleading_channels = HEJFOG::Subleading::uno;
HEJ::Ranlux64 ran{};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
HEJ::ScaleGenerator{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
},
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
ran
};
double xs = 0., xs_err = 0.;
for (int trials = 0; trials < config.events; ++trials){
auto ev = generator.gen_event();
- if(ev.type() == HEJ::event_type::FKL) continue;
if(generator.status() != good) continue;
- ev.central().weight *= invGeV2_to_pb;
- ev.central().weight /= config.events;
+ assert(ev);
+ if(ev->type() == HEJ::event_type::FKL) continue;
+ ev->central().weight *= invGeV2_to_pb;
+ ev->central().weight /= config.events;
- xs += ev.central().weight;
- xs_err += ev.central().weight*ev.central().weight;
+ xs += ev->central().weight;
+ xs_err += ev->central().weight*ev->central().weight;
}
xs_err = std::sqrt(xs_err);
std::cout << xs_ref << " ~ " << xs << " +- " << xs_err << std::endl;
assert(std::abs(xs - xs_ref) < 3*xs_err);
assert(xs_err < 0.05*xs);
}
diff --git a/FixedOrderGen/t/h_5j.cc b/FixedOrderGen/t/h_5j.cc
index 6aa3d40..a1b60e8 100644
--- a/FixedOrderGen/t/h_5j.cc
+++ b/FixedOrderGen/t/h_5j.cc
@@ -1,63 +1,64 @@
#ifdef NDEBUG
#undef NDEBUG
#endif
// This is a regression test
// the reference cross section has not been checked against any other program
#include <algorithm>
#include <cassert>
#include <cmath>
#include <iostream>
#include "config.hh"
#include "EventGenerator.hh"
#include "HEJ/Ranlux64.hh"
#include "HEJ/Event.hh"
#include "HEJ/MatrixElement.hh"
#include "HEJ/PDF.hh"
using namespace HEJFOG;
int main(){
constexpr double invGeV2_to_pb = 389379292.;
constexpr double xs_ref = 0.252273; // +- 0.00657742
//calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
auto config = load_config("config_h_2j.yml");
config.process.njets = 5;
HEJ::Ranlux64 ran{};
HEJFOG::EventGenerator generator{
config.process,
config.beam,
HEJ::ScaleGenerator{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
},
config.jets,
config.pdf_id,
config.subleading_fraction,
config.subleading_channels,
config.particles_properties,
config.Higgs_coupling,
ran
};
double xs = 0., xs_err = 0.;
for (int trials = 0; trials < config.events; ++trials){
auto ev = generator.gen_event();
if(generator.status() != good) continue;
- ev.central().weight *= invGeV2_to_pb;
- ev.central().weight /= config.events;
+ assert(ev);
+ ev->central().weight *= invGeV2_to_pb;
+ ev->central().weight /= config.events;
- xs += ev.central().weight;
- xs_err += ev.central().weight*ev.central().weight;
+ xs += ev->central().weight;
+ xs_err += ev->central().weight*ev->central().weight;
}
xs_err = std::sqrt(xs_err);
std::cout << xs_ref << " ~ " << xs << " +- " << xs_err << std::endl;
assert(std::abs(xs - xs_ref) < 3*xs_err);
assert(xs_err < 0.06*xs);
}
diff --git a/doc/developer_manual/biblio.bib b/doc/developer_manual/biblio.bib
index cd82f36..a2bfb84 100644
--- a/doc/developer_manual/biblio.bib
+++ b/doc/developer_manual/biblio.bib
@@ -1,138 +1,173 @@
@Article{Andersen:2008gc,
author = "Andersen, Jeppe R. and Del Duca, Vittorio and White, Chris
D.",
title = "{Higgs Boson Production in Association with Multiple Hard
Jets}",
journal = "JHEP",
volume = "02",
year = "2009",
pages = "015",
eprint = "0808.3696",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
doi = "10.1088/1126-6708/2009/02/015",
SLACcitation = "%%CITATION = 0808.3696;%%"
}
@Article{Andersen:2008ue,
author = "Andersen, Jeppe R. and White, Chris D.",
title = "{A New Framework for Multijet Predictions and its
application to Higgs Boson production at the LHC}",
journal = "Phys. Rev.",
volume = "D78",
year = "2008",
pages = "051501",
eprint = "0802.2858",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
doi = "10.1103/PhysRevD.78.051501",
SLACcitation = "%%CITATION = 0802.2858;%%"
}
@article{Alwall:2006yp,
author = "Alwall, Johan and others",
title = "{A Standard format for Les Houches event files}",
booktitle = "{Monte Carlos for the LHC: A Workshop on the Tools for
LHC Event Simulation (MC4LHC) Geneva, Switzerland, July
17-16, 2006}",
journal = "Comput. Phys. Commun.",
volume = "176",
year = "2007",
pages = "300-304",
doi = "10.1016/j.cpc.2006.11.010",
eprint = "hep-ph/0609017",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "FERMILAB-PUB-06-337-T, CERN-LCGAPP-2006-03",
SLACcitation = "%%CITATION = HEP-PH/0609017;%%"
}
@article{Andersen:2017kfc,
author = "Andersen, Jeppe R. and Hapola, Tuomas and Maier, Andreas
and Smillie, Jennifer M.",
title = "{Higgs Boson Plus Dijets: Higher Order Corrections}",
journal = "JHEP",
volume = "09",
year = "2017",
pages = "065",
doi = "10.1007/JHEP09(2017)065",
eprint = "1706.01002",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "EDINBURGH-2017-11, IPPP-17-33, DCPT-17-66, MCNET-17-9",
SLACcitation = "%%CITATION = ARXIV:1706.01002;%%"
}
@article{Andersen:2018tnm,
author = "Andersen, Jeppe R. and Hapola, Tuomas and Heil, Marian
and Maier, Andreas and Smillie, Jennifer M.",
title = "{Higgs-boson plus Dijets: Higher-Order Matching for
High-Energy Predictions}",
year = "2018",
eprint = "1805.04446",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "DCPT/18/66, IPPP/18/33, MCnet-18-10, DCPT-18-66,
IPPP-18-33, MCNET-18-10",
SLACcitation = "%%CITATION = ARXIV:1805.04446;%%"
}
@article{Andersen:2012gk,
author = "Andersen, Jeppe R. and Hapola, Tuomas and Smillie,
Jennifer M.",
title = "{W Plus Multiple Jets at the LHC with High Energy Jets}",
journal = "JHEP",
volume = "09",
year = "2012",
pages = "047",
doi = "10.1007/JHEP09(2012)047",
eprint = "1206.6763",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "EDINBURGH-2012-13, IPPP-12-45, DCPT-12-90,
CP3-ORIGINS-2012-017, DIAS-2012-18, --DIAS-2012-18",
SLACcitation = "%%CITATION = ARXIV:1206.6763;%%"
}
@article{Andersen:2016vkp,
author = "Andersen, Jeppe R. and Medley, Jack J. and Smillie,
Jennifer M.",
title = "{$Z/\gamma^{∗}$ plus multiple hard jets in high energy
collisions}",
journal = "JHEP",
volume = "05",
year = "2016",
pages = "136",
doi = "10.1007/JHEP05(2016)136",
eprint = "1603.05460",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "EDINBURGH-2016-03, IPPP-16-19, DCPT-16-38, MCNET-16-08",
SLACcitation = "%%CITATION = ARXIV:1603.05460;%%"
}
@article{DelDuca:2003ba,
author = "Del Duca, V. and Kilgore, W. and Oleari, C. and Schmidt,
C.R. and Zeppenfeld, D.",
title = "{Kinematical limits on Higgs boson production via gluon
fusion in association with jets}",
journal = "Phys.Rev.",
volume = "D67",
pages = "073003",
doi = "10.1103/PhysRevD.67.073003",
year = "2003",
eprint = "hep-ph/0301013",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "DCPT-02-148, DFTT-20-2002, IPPP-02-74, MADPH-02-1276,
MSUHEP-20620",
SLACcitation = "%%CITATION = HEP-PH/0301013;%%",
}
@article{DelDuca:2001fn,
author = "Del Duca, V. and Kilgore, W. and Oleari, C. and Schmidt,
C. and Zeppenfeld, D.",
title = "{Gluon fusion contributions to H + 2 jet production}",
journal = "Nucl.Phys.",
volume = "B616",
pages = "367-399",
doi = "10.1016/S0550-3213(01)00446-1",
year = "2001",
eprint = "hep-ph/0108030",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "MADPH-01-1235, BNL-HET-01-28, MSUHEP-10709, DFTT-19-2001",
SLACcitation = "%%CITATION = HEP-PH/0108030;%%",
}
+@article{Andersen:2011zd,
+ author = "Andersen, Jeppe R. and Lonnblad, Leif and Smillie,
+ Jennifer M.",
+ title = "{A Parton Shower for High Energy Jets}",
+ journal = "JHEP",
+ volume = "07",
+ year = "2011",
+ pages = "110",
+ doi = "10.1007/JHEP07(2011)110",
+ eprint = "1104.1316",
+ archivePrefix = "arXiv",
+ primaryClass = "hep-ph",
+ reportNumber = "CERN-PH-TH-2011-072, CP3-ORIGINS-2011-14,
+ EDINBURGH-2011-16, LU-TP-11-15, MCNET-11-12, LU-TP
+ --11-15",
+ SLACcitation = "%%CITATION = ARXIV:1104.1316;%%"
+}
+@article{Andersen:2017sht,
+ author = "Andersen, Jeppe R. and Brooks, Helen M. and Lönnblad,
+ Leif",
+ title = "{Merging High Energy with Soft and Collinear Logarithms
+ using HEJ and PYTHIA}",
+ journal = "JHEP",
+ volume = "09",
+ year = "2018",
+ pages = "074",
+ doi = "10.1007/JHEP09(2018)074",
+ eprint = "1712.00178",
+ archivePrefix = "arXiv",
+ primaryClass = "hep-ph",
+ reportNumber = "CPT/17/184, IPPP/17/92, LU-TP 17-38, MCnet-17-22,
+ CoEPP-MN-17-22, CPT-17-184, IPPP-17-92, LU-TP-17-38,
+ MCNET-17-22, COEPP-MN-17-22",
+ SLACcitation = "%%CITATION = ARXIV:1712.00178;%%"
+}
diff --git a/doc/developer_manual/developer_manual.tex b/doc/developer_manual/developer_manual.tex
index de04414..8fafed2 100644
--- a/doc/developer_manual/developer_manual.tex
+++ b/doc/developer_manual/developer_manual.tex
@@ -1,1436 +1,1535 @@
\documentclass[a4paper,11pt]{article}
\usepackage{fourier}
\usepackage[T1]{fontenc}
\usepackage{microtype}
\usepackage{geometry}
\usepackage{enumitem}
\setlist[description]{leftmargin=\parindent,labelindent=\parindent}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage[utf8x]{inputenc}
\usepackage{graphicx}
\usepackage{xcolor}
\usepackage{todonotes}
\usepackage{listings}
\usepackage{xspace}
\usepackage{tikz}
+\usepackage{subcaption}
\usetikzlibrary{arrows.meta}
\usetikzlibrary{shapes}
\usetikzlibrary{calc}
\usepackage[colorlinks,linkcolor={blue!50!black}]{hyperref}
\graphicspath{{build/figures/}{figures/}}
\emergencystretch \hsize
\newcommand{\HEJ}{{\tt HEJ}\xspace}
\newcommand{\HIGHEJ}{\emph{High Energy Jets}\xspace}
\newcommand{\cmake}{\href{https://cmake.org/}{cmake}\xspace}
\newcommand{\html}{\href{https://www.w3.org/html/}{html}\xspace}
\newcommand{\YAML}{\href{http://yaml.org/}{YAML}\xspace}
\newcommand{\QCDloop}{\href{https://github.com/scarrazza/qcdloop}{QCDloop}\xspace}
\newcommand{\as}{\alpha_s}
\DeclareRobustCommand{\mathgraphics}[1]{\vcenter{\hbox{\includegraphics{#1}}}}
\def\spa#1.#2{\left\langle#1\,#2\right\rangle}
\def\spb#1.#2{\left[#1\,#2\right]} \def\spaa#1.#2.#3{\langle\mskip-1mu{#1} |
#2 | {#3}\mskip-1mu\rangle} \def\spbb#1.#2.#3{[\mskip-1mu{#1} | #2 |
{#3}\mskip-1mu]} \def\spab#1.#2.#3{\langle\mskip-1mu{#1} | #2 |
{#3}\mskip-1mu\rangle} \def\spba#1.#2.#3{\langle\mskip-1mu{#1}^+ | #2 |
{#3}^+\mskip-1mu\rangle} \def\spav#1.#2.#3{\|\mskip-1mu{#1} | #2 |
{#3}\mskip-1mu\|^2} \def\jc#1.#2.#3{j^{#1}_{#2#3}}
\definecolor{darkgreen}{rgb}{0,0.4,0}
\lstset{ %
backgroundcolor=\color{lightgray}, % choose the background color; you must add \usepackage{color} or \usepackage{xcolor}
basicstyle=\footnotesize\usefont{T1}{DejaVuSansMono-TLF}{m}{n}, % the size of the fonts that are used for the code
breakatwhitespace=false, % sets if automatic breaks should only happen at whitespace
breaklines=false, % sets automatic line breaking
captionpos=t, % sets the caption-position to bottom
commentstyle=\color{red}, % comment style
deletekeywords={...}, % if you want to delete keywords from the given language
escapeinside={\%*}{*)}, % if you want to add LaTeX within your code
extendedchars=true, % lets you use non-ASCII characters; for 8-bits encodings only, does not work with UTF-8
frame=false, % adds a frame around the code
keepspaces=true, % keeps spaces in text, useful for keeping indentation of code (possibly needs columns=flexible)
keywordstyle=\color{blue}, % keyword style
otherkeywords={}, % if you want to add more keywords to the set
numbers=none, % where to put the line-numbers; possible values are (none, left, right)
numbersep=5pt, % how far the line-numbers are from the code
rulecolor=\color{black}, % if not set, the frame-color may be changed on line-breaks within not-black text (e.g. comments (green here))
showspaces=false, % show spaces everywhere adding particular underscores; it overrides 'showstringspaces'
showstringspaces=false, % underline spaces within strings only
showtabs=false, % show tabs within strings adding particular underscores
stepnumber=2, % the step between two line-numbers. If it's 1, each line will be numbered
stringstyle=\color{gray}, % string literal style
tabsize=2, % sets default tabsize to 2 spaces
title=\lstname,
emph={},
emphstyle=\color{darkgreen}
}
\begin{document}
\tikzstyle{mynode}=[rectangle split,rectangle split parts=2, draw,rectangle split part fill={lightgray, none}]
\title{HEJ 2 developer manual}
\author{}
\maketitle
\tableofcontents
\newpage
\section{Overview}
\label{sec:overview}
HEJ 2 is a C++ program and library implementing an algorithm to
apply \HIGHEJ resummation~\cite{Andersen:2008ue,Andersen:2008gc} to
pre-generated fixed-order events. This document is intended to give an
overview over the concepts and structure of this implementation.
\subsection{Project structure}
\label{sec:project}
HEJ 2 is developed under the \href{https://git-scm.com/}{git}
version control system. The main repository is on the IPPP
\href{https://gitlab.com/}{gitlab} server under
\url{https://gitlab.dur.scotgrid.ac.uk/hej/hej}. To get a local
copy, get an account on the gitlab server and use
\begin{lstlisting}[language=sh,caption={}]
git clone git@gitlab.dur.scotgrid.ac.uk:hej/hej.git
\end{lstlisting}
This should create a directory \texttt{hej} with the following
contents:
\begin{description}
\item[doc:] Contains additional documentation, see section~\ref{sec:doc}.
\item[include:] Contains the C++ header files.
\item[src:] Contains the C++ source files.
\item[t:] Contains the source code for the automated tests.
\item[CMakeLists.txt:] Configuration file for the \cmake build
system. See section~\ref{sec:cmake}.
\item[cmake:] Auxiliary files for \cmake. This includes modules for
finding installed software in \texttt{cmake/Modules} and templates for
code generation during the build process in \texttt{cmake/Templates}.
\item[config.yml:] Sample configuration file for running HEJ 2.
\item[FixedOrderGen:] Contains the code for the fixed-order generator,
see section~\ref{sec:HEJFOG}.
\end{description}
In the following all paths are given relative to the
\texttt{hej} directory.
\subsection{Documentation}
\label{sec:doc}
The \texttt{doc} directory contains user documentation in
\texttt{doc/sphinx} and the configuration to generate source code
documentation in \texttt{doc/doxygen}.
The user documentation explains how to install and run HEJ 2. The
format is
\href{http://docutils.sourceforge.net/rst.html}{reStructuredText}, which
is mostly human-readable. Other formats, like \html, can be generated with the
\href{http://www.sphinx-doc.org/en/master/}{sphinx} generator with
\begin{lstlisting}[language=sh,caption={}]
make html
\end{lstlisting}
To document the source code we use
\href{https://www.stack.nl/~dimitri/doxygen/}{doxygen}. To generate
\html documentation, use the command
\begin{lstlisting}[language=sh,caption={}]
doxygen Doxyfile
\end{lstlisting}
in the \texttt{doc/doxygen} directory.
\subsection{Build system}
\label{sec:cmake}
For the most part, HEJ 2 is a library providing classes and
functions that can be used to add resummation to fixed-order events. In
addition, there is a relatively small executable program leveraging this
library to read in events from an input file and produce resummation
events. Both the library and the program are built and installed with
the help of \cmake.
Debug information can be turned on by using
\begin{lstlisting}[language=sh,caption={}]
cmake base/directory -DCMAKE_BUILD_TYPE=Debug
make install
\end{lstlisting}
This facilitates the use of debuggers like \href{https://www.gnu.org/software/gdb/}{gdb}.
The main \cmake configuration file is \texttt{CMakeLists.txt}. It defines the
compiler flags, software prerequisites, header and source files used to
build HEJ 2, and the automated tests.
\texttt{cmake/Modules} contains module files that help with the
detection of the software prerequisites and \texttt{cmake/Templates}
template files for the automatic generation of header and
source files. For example, this allows to only keep the version
information in one central location (\texttt{CMakeLists.txt}) and
automatically generate a header file from the template \texttt{Version.hh.in} to propagate this to the C++ code.
\subsection{General coding guidelines}
\label{sec:notes}
The goal is to make the HEJ 2 code well-structured and
readable. Here are a number of guidelines to this end.
\begin{description}
\item[Observe the boy scout rule.] Always leave the code cleaner
than how you found it. Ugly hacks can be useful for testing, but
shouldn't make their way into the main branch.
\item[Ask if something is unclear.] Often there is a good reason why
code is written the way it is. Sometimes that reason is only obvious to
the original author (use \lstinline!git blame! to find them), in which
case they should be poked to add a comment. Sometimes there is no good
reason, but nobody has had the time to come up with something better,
yet. In some places the code might just be bad.
\item[Don't break tests.] There are a number of tests in the \texttt{t}
directory, which can be run with \lstinline!make test!. Ideally, all
tests should run successfully in each git revision. If your latest
commit broke a test and you haven't pushed to the central repository
yet, you can fix it with \lstinline!git commit --amend!. If an earlier
local commit broke a test, you can use \lstinline!git rebase -i! if
you feel confident. Additionally each \lstinline!git push! is also
automatically tested via the GitLab CI (see appendix~\ref{sec:gitlabCI}).
\item[Test your new code.] When you add some new functionality, also add an
automated test. This can be useful even if you don't know the
``correct'' result because it prevents the code from changing its behaviour
silently in the future. \href{http://www.valgrind.org/}{valgrind} is a
very useful tool to detect potential memory leaks.
\item[Stick to the coding style.] It is somewhat easier to read code
that has a uniform coding and indentation style. We don't have a
strict style, but it helps if your code looks similar to what is
already there.
\end{description}
\section{Program flow}
\label{sec:flow}
A run of the HEJ 2 program has three stages: initialisation,
event processing, and cleanup. The following sections outline these
stages and their relations to the various classes and functions in the
code. Unless denoted otherwise, all classes and functions are part of
the \lstinline!HEJ! namespace. The code for the HEJ 2 program is
in \texttt{src/bin/HEJ.cc}, all other code comprises the HEJ 2
library. Classes and free functions are usually implemented in header
and source files with a corresponding name, i.e. the code for
\lstinline!MyClass! can usually be found in
\texttt{include/HEJ/MyClass.hh} and \texttt{src/MyClass.cc}.
\subsection{Initialisation}
\label{sec:init}
The first step is to load and parse the \YAML configuration file. The
entry point for this is the \lstinline!load_config! function and the
related code can be found in \texttt{include/HEJ/YAMLreader.hh},
\texttt{include/HEJ/config.hh} and the corresponding \texttt{.cc} files
in the \texttt{src} directory. The implementation is based on the
\href{https://github.com/jbeder/yaml-cpp}{yaml-cpp} library.
The \lstinline!load_config! function returns a \lstinline!Config! object
containing all settings. To detect potential mistakes as early as
possible, we throw an exception whenever one of the following errors
occurs:
\begin{itemize}
\item There is an unknown option in the \YAML file.
\item A setting is invalid, for example a string is given where a number
would be expected.
\item An option value is not set.
\end{itemize}
The third rule is sometimes relaxed for ``advanced'' settings with an
obvious default, like for importing custom scales or analyses.
The information stored in the \lstinline!Config! object is then used to
initialise various objects required for the event processing stage
described in section~\ref{sec:processing}. First, the
\lstinline!get_analysis! function creates an object that inherits from
the \lstinline!Analysis! interface.\footnote{In the context of C++ the
proper technical expression is ``pure abstract class''.} Using an
interface allows us to decide the concrete type of the analysis at run
time instead of having to make a compile-time decision. Depending on the
settings, \lstinline!get_analysis! creates either a user-defined
analysis loaded from an external library (see the user documentation
\url{https://hej.web.cern.ch/HEJ/doc/current/user/}) or the default \lstinline!EmptyAnalysis!, which does
nothing.
Together with a number of further objects, whose roles are described in
section~\ref{sec:processing}, we also initialise the global random
number generator. We again use an interface to defer deciding the
concrete type until the program is actually run. Currently, we support the
\href{https://mixmax.hepforge.org/}{MIXMAX}
(\texttt{include/HEJ/Mixmax.hh}) and Ranlux64
(\texttt{include/HEJ/Ranlux64.hh}) random number generators, both are provided
by \href{http://proj-clhep.web.cern.ch/}{CLHEP}.
We also set up a \lstinline!LHEF::Reader! object (see
\href{http://home.thep.lu.se/~leif/LHEF/}{\texttt{include/LHEF/LHEF.h}}) for
reading events from a file in the Les
Houches event file format~\cite{Alwall:2006yp}. A small wrapper around
the
\href{https://www.boost.org/doc/libs/1_67_0/libs/iostreams/doc/index.html}{boost
iostreams} library allows us to also read event files compressed with
\href{https://www.gnu.org/software/gzip/}{gzip}. The wrapper code is in
\texttt{include/HEJ/stream.hh} and the \texttt{src/stream.cc}.
\subsection{Event processing}
\label{sec:processing}
In the second stage events are continously read from the event
file. After jet clustering, a number of corresponding resummation events
are generated for each input event and fed into the analysis and a
number of output files. The roles of various classes and functions are
illustrated in the following flow chart:
\begin{center}
\begin{tikzpicture}[node distance=2cm and 5mm]
\node (reader) [mynode]
{\lstinline!LHEF::Reader::readEvent!\nodepart{second}{read event}};
\node
- (cluster) [mynode,below=of reader]
- {\lstinline!Event! constructor\nodepart{second}{cluster jets}};
+ (data) [mynode,below=of reader]
+ {\lstinline!Event::EventData! constructor\nodepart{second}{convert to \HEJ object}};
+ \node
+ (cluster) [mynode,below=of data]
+ {\lstinline!Event::EventData::cluster!\nodepart{second}{cluster jets \&
+ classify \lstinline!EventType!}};
\node
(resum) [mynode,below=of cluster]
{\lstinline!EventReweighter::reweight!\nodepart{second}{perform resummation}};
\node
(cut) [mynode,below=of resum]
{\lstinline!Analysis::pass_cuts!\nodepart{second}{apply cuts}};
\node
(fill) [mynode,below left=of cut]
{\lstinline!Analysis::fill!\nodepart{second}{analyse event}};
\node
(write) [mynode,below right=of cut]
{\lstinline!CombinedEventWriter::write!\nodepart{second}{write out event}};
\node
(control) [below=of cut] {};
\draw[-{Latex[length=3mm, width=1.5mm]}]
- (reader.south) -- node[left] {\lstinline!LHEF::HEPEUP!} (cluster.north);
+ (reader.south) -- node[left] {\lstinline!LHEF::HEPEUP!} (data.north);
+ \draw[-{Latex[length=3mm, width=1.5mm]}]
+ (data.south) -- node[left] {\lstinline!Event::EventData!} (cluster.north);
\draw[-{Latex[length=3mm, width=1.5mm]}]
(cluster.south) -- node[left] {\lstinline!Event!} (resum.north);
\draw[-{Latex[length=3mm, width=1.5mm]}]
(resum.south) -- (cut.north);
\draw[-{Latex[length=3mm, width=1.5mm]}]
($(resum.south)+(7mm, 0cm)$) -- ($(cut.north)+(7mm, 0cm)$);
\draw[-{Latex[length=3mm, width=1.5mm]}]
($(resum.south)-(7mm, 0cm)$) -- node[left] {\lstinline!Event!} ($(cut.north)-(7mm, 0cm)$);
\draw[-{Latex[length=3mm, width=1.5mm]}]
($(cut.south)-(3mm,0mm)$) .. controls ($(control)-(3mm,0mm)$) ..node[left] {\lstinline!Event!} (fill.east);
\draw[-{Latex[length=3mm, width=1.5mm]}]
($(cut.south)-(3mm,0mm)$) .. controls ($(control)-(3mm,0mm)$) .. (write.west);
\draw[-{Latex[length=3mm, width=1.5mm]}]
($(cut.south)+(3mm,0mm)$) .. controls ($(control)+(3mm,0mm)$) .. (fill.east);
\draw[-{Latex[length=3mm, width=1.5mm]}]
($(cut.south)+(3mm,0mm)$) .. controls ($(control)+(3mm,0mm)$) ..node[right] {\lstinline!Event!} (write.west);
\end{tikzpicture}
\end{center}
-The resummation is performed by the \lstinline!EventReweighter! class,
-which is described in more detail in section~\ref{sec:resum}. The
-\lstinline!CombinedEventWriter! writes events to zero or more output
-files. To this end, it contains a number of objects implementing the
-\lstinline!EventWriter! interface. These event writers typically write
-the events to a file in a given format. We currently have the
-\lstinline!LesHouchesWriter! for event files in the Les Houches Event
-File format and the \lstinline!HepMCWriter! for the
+
+\lstinline!EventData! is an intermediate container, its members are completely
+accessible. In contrast after jet clustering and classification the phase space
+inside \lstinline!Event! can not be changed any more
+(\href{https://wikipedia.org/wiki/Builder_pattern}{Builder design pattern}). The
+resummation is performed by the \lstinline!EventReweighter! class, which is
+described in more detail in section~\ref{sec:resum}. The
+\lstinline!CombinedEventWriter! writes events to zero or more output files. To
+this end, it contains a number of objects implementing the
+\lstinline!EventWriter! interface. These event writers typically write the
+events to a file in a given format. We currently have the
+\lstinline!LesHouchesWriter! for event files in the Les Houches Event File
+format and the \lstinline!HepMCWriter! for the
\href{https://hepmc.web.cern.ch/hepmc/}{HepMC} format (Version 2 and 3).
\subsection{Resummation}
\label{sec:resum}
In the \lstinline!EventReweighter::reweight! member function, we first
classify the input fixed-order event (FKL, unordered, non-HEJ, \dots)
and decide according to the user settings whether to discard, keep, or
resum the event. If we perform resummation for the given event, we
generate a number of trial \lstinline!PhaseSpacePoint! objects. Phase
space generation is discussed in more detail in
section~\ref{sec:pspgen}. We then perform jet clustering according to
the settings for the resummation jets on each
\lstinline!PhaseSpacePoint!, update the factorisation and
renormalisation scale in the resulting \lstinline!Event! and reweight it
according to the ratio of pdf factors and \HEJ matrix elements between
resummation and original fixed-order event:
\begin{center}
- \begin{tikzpicture}[node distance=2cm and 5mm]
+ \begin{tikzpicture}[node distance=1.5cm and 5mm]
\node (in) {};
\node (treat) [diamond,draw,below=of in,minimum size=3.5cm,
label={[anchor=west, inner sep=8pt]west:discard},
label={[anchor=east, inner sep=14pt]east:keep},
label={[anchor=south, inner sep=20pt]south:reweight}
] {};
\draw (treat.north west) -- (treat.south east);
\draw (treat.north east) -- (treat.south west);
\node
(psp) [mynode,below=of treat]
{\lstinline!PhaseSpacePoint! constructor};
\node
(cluster) [mynode,below=of psp]
- {\lstinline!Event! constructor\nodepart{second}{cluster jets}};
+ {\lstinline!Event::EventData::cluster!\nodepart{second}{cluster jets}};
+ \node
+ (colour) [mynode,below=of cluster]
+ {\lstinline!Event::generate_colours()!\nodepart{second}{generate particle colour}};
\node
- (gen_scales) [mynode,below=of cluster]
+ (gen_scales) [mynode,below=of colour]
{\lstinline!ScaleGenerator::operator()!\nodepart{second}{update scales}};
\node
(rescale) [mynode,below=of gen_scales]
{\lstinline!PDF::pdfpt!,
\lstinline!MatrixElement!\nodepart{second}{reweight}};
\node (out) [below of=rescale] {};
+
\draw[-{Latex[length=3mm, width=1.5mm]}]
(in.south) -- node[left] {\lstinline!Event!} (treat.north);
\draw[-{Latex[length=3mm, width=1.5mm]}]
(treat.south) -- node[left] {\lstinline!Event!} (psp.north);
+
\draw[-{Latex[length=3mm, width=1.5mm]}]
(psp.south) -- (cluster.north);
\draw[-{Latex[length=3mm, width=1.5mm]}]
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\draw[-{Latex[length=3mm, width=1.5mm]}]
($(psp.south)-(7mm, 0cm)$) -- node[left]
{\lstinline!PhaseSpacePoint!} ($(cluster.north)-(7mm, 0cm)$);
+
\draw[-{Latex[length=3mm, width=1.5mm]}]
- (cluster.south) -- (gen_scales.north);
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\draw[-{Latex[length=3mm, width=1.5mm]}]
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+
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($(rescale.south)-(7mm, 0cm)$) -- node[left]
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-- node[left] {\lstinline!Event!} (helper |- gen_scales.east) -- (gen_scales.east)
;
\end{tikzpicture}
\end{center}
-
\subsection{Phase space point generation}
\label{sec:pspgen}
The resummed and matched \HEJ cross section for pure jet production of
FKL configurations is given by (cf. eq. (3) of~\cite{Andersen:2018tnm})
\begin{align}
\label{eq:resumdijetFKLmatched2}
% \begin{split}
\sigma&_{2j}^\mathrm{resum, match}=\sum_{f_1, f_2}\ \sum_m
\prod_{j=1}^m\left(
\int_{p_{j\perp}^B=0}^{p_{j\perp}^B=\infty}
\frac{\mathrm{d}^2\mathbf{p}_{j\perp}^B}{(2\pi)^3}\ \int
\frac{\mathrm{d} y_j^B}{2} \right) \
(2\pi)^4\ \delta^{(2)}\!\!\left(\sum_{k=1}^{m}
\mathbf{p}_{k\perp}^B\right)\nonumber\\
&\times\ x_a^B\ f_{a, f_1}(x_a^B, Q_a^B)\ x_b^B\ f_{b, f_2}(x_b^B, Q_b^B)\
\frac{\overline{\left|\mathcal{M}_\text{LO}^{f_1f_2\to f_1g\cdots
gf_2}\big(\big\{p^B_j\big\}\big)\right|}^2}{(\hat {s}^B)^2}\nonumber\\
& \times (2\pi)^{-4+3m}\ 2^m \nonumber\\
&\times\ \sum_{n=2}^\infty\
\int_{p_{1\perp}=p_{\perp,\mathrm{min}} }^{p_{1\perp}=\infty}
\frac{\mathrm{d}^2\mathbf{p}_{1\perp}}{(2\pi)^3}\
\int_{p_{n\perp}=p_{\perp,\mathrm{min}}}^{p_{n\perp}=\infty}
\frac{\mathrm{d}^2\mathbf{p}_{n\perp}}{(2\pi)^3}\
\prod_{i=2}^{n-1}\int_{p_{i\perp}=\lambda}^{p_{i\perp}=\infty}
\frac{\mathrm{d}^2\mathbf{p}_{i\perp}}{(2\pi)^3}\ (2\pi)^4\ \delta^{(2)}\!\!\left(\sum_{k=1}^n
\mathbf{p}_{k\perp}\right )\\
&\times \ \mathbf{T}_y \prod_{i=1}^n
\left(\int \frac{\mathrm{d} y_i}{2}\right)\
\mathcal{O}_{mj}^e\
\left(\prod_{l=1}^{m-1}\delta^{(2)}(\mathbf{p}_{\mathcal{J}_{l}\perp}^B -
\mathbf{j}_{l\perp})\right)\
\left(\prod_{l=1}^m\delta(y^B_{\mathcal{J}_l}-y_{\mathcal{J}_l})\right)
\ \mathcal{O}_{2j}(\{p_i\})\nonumber\\
&\times \frac{(\hat{s}^B)^2}{\hat{s}^2}\ \frac{x_a f_{a,f_1}(x_a, Q_a)\ x_b f_{b,f_2}(x_b, Q_b)}{x_a^B\ f_{a,f_1}(x_a^B, Q_a^B)\ x_b^B\ f_{b,f_2}(x_b^B, Q_b^B)}\ \frac{\overline{\left|\mathcal{M}_{\mathrm{HEJ}}^{f_1 f_2\to f_1 g\cdots
gf_2}(\{ p_i\})\right|}^2}{\overline{\left|\mathcal{M}_\text{LO, HEJ}^{f_1f_2\to f_1g\cdots
gf_2}\big(\big\{p^B_j\big\}\big)\right|}^{2}} \,.\nonumber
% \end{split}
\end{align}
The first two lines correspond to the generation of the fixed-order
input events with incoming partons $f_1, f_2$ and outgoing momenta
$p_j^B$, where $\mathbf{p}_{j\perp}^B$ and $y_j^B$ denote the respective
transverse momentum and rapidity. Note that, at leading order, these
coincide with the fixed-order jet momenta $p_{\mathcal{J}_j}^B$.
$f_{a,f_1}(x_a, Q_a),f_{b,f_2}(x_b, Q_b)$ are the pdf factors for the incoming partons with
momentum fractions $x_a$ and $x_b$. The square of the partonic
centre-of-mass energy is denoted by $\hat{s}^B$ and
$\mathcal{M}_\text{LO}^{f_1f_2\to f_1g\cdots gf_2}$ is the
leading-order matrix element.
The third line is a factor accounting for the different multiplicities
between fixed-order and resummation events. Lines four and five are
the integration over the resummation phase space described in this
section. $p_i$ are the momenta of the outgoing partons in resummation
phase space. $\mathbf{T}_y$ denotes rapidity
ordering and $\mathcal{O}_{mj}^e$ projects out the exclusive $m$-jet
component. The relation between resummation and fixed-order momenta is
fixed by the $\delta$ functions. The first sets each transverse fixed-order jet
momentum to some function $\mathbf{j_{l\perp}}$ of the resummation
momenta. The exact form is described in section~\ref{sec:ptj_res}. The second
$\delta$ forces the rapidities of resummation and fixed-order jets to be
the same. Finally, the last line is the reweighting of pdf and matrix
element factors already shown in section~\ref{sec:resum}.
There are two kinds of cut-off in the integration over the resummation
partons. $\lambda$ is a technical cut-off connected to the cancellation
of infrared divergencies between real and virtual corrections. Its
numerical value is set in
\texttt{include/HEJ/Constants.h}. $p_{\perp,\mathrm{min}}$ regulates
and \emph{uncancelled} divergence in the extremal parton momenta. Its
size is set by the user configuration \url{https://hej.web.cern.ch/HEJ/doc/current/user/HEJ.html#settings}.
It is straightforward to generalise eq.~(\ref{eq:resumdijetFKLmatched2})
to unordered configurations and processes with additional colourless
emissions, for example a Higgs or electroweak boson. In the latter case only
the fixed-order integration and the matrix elements change.
\subsubsection{Gluon Multiplicity}
\label{sec:psp_ng}
The first step in evaluating the resummation phase space in
eq.~(\ref{eq:resumdijetFKLmatched2}) is to randomly pick terms in the
sum over the number of emissions. This sampling of the gluon
multiplicity is done in the \lstinline!PhaseSpacePoint::sample_ng!
function in \texttt{src/PhaseSpacePoint.cc}.
The typical number of extra emissions depends strongly on the rapidity
span of the underlying fixed-order event. Let us, for example, consider
a fixed-order FKL-type multi-jet configuration with rapidities
$y_{j_f},\,y_{j_b}$ of the most forward and backward jets,
respectively. By eq.~(\ref{eq:resumdijetFKLmatched2}), the jet
multiplicity and the rapidity of each jet are conserved when adding
resummation. This implies that additional hard radiation is restricted
to rapidities $y$ within a region $y_{j_b} \lesssim y \lesssim
y_{j_f}$. Within \HEJ, we require the most forward and most backward
emissions to be hard \todo{specify how hard} in order to avoid divergences, so this constraint
in fact applies to \emph{all} additional radiation.
To simplify the remaining discussion, let us remove the FKL rapidity
ordering
\begin{equation}
\label{eq:remove_y_order}
\mathbf{T}_y \prod_{i=1}^n\int \frac{\mathrm{d}y_i}{2} =
\frac{1}{n!}\prod_{i=1}^n\int
\frac{\mathrm{d}y_i}{2}\,,
\end{equation}
where all rapidity integrals now cover a region which is approximately
bounded by $y_{j_b}$ and $y_{j_f}$. Each of the $m$ jets has to contain at least
one parton; selecting random emissions we can rewrite the phase space
integrals as
\begin{equation}
\label{eq:select_jets}
\frac{1}{n!}\prod_{i=1}^n\int [\mathrm{d}p_i] =
\left(\prod_{i=1}^{m}\int [\mathrm{d}p_i]\ {\cal J}_i(p_i)\right)
\frac{1}{n_g!}\prod_{i=m+1}^{m+n_g}\int [\mathrm{d}p_i]
\end{equation}
with jet selection functions
\begin{equation}
\label{eq:def_jet_selection}
{\cal J}_i(p) =
\begin{cases}
1 &p\text{ clustered into jet }i\\
0 & \text{otherwise}
\end{cases}
\end{equation}
and $n_g \equiv n - m$. Here and in the following we use the short-hand
notation $[\mathrm{d}p_i]$ to denote the phase-space measure for parton
$i$. As is evident from eq.~\eqref{eq:select_jets}, adding an extra emission
$n_g+1$ introduces a suppression factor $\tfrac{1}{n_g+1}$. However, the
additional phase space integral also results in an enhancement proportional
to $\Delta y_{j_f j_b} = y_{j_f} - y_{j_b}$. This is a result of the
rapidity-independence of the MRK limit of the integrand, consisting of the
matrix elements divided by the flux factor. Indeed, we observe that the
typical number of gluon emissions is to a good approximation proportional to
the rapidity separation and the phase space integral is dominated by events
with $n_g \approx \Delta y_{j_f j_b}$.
For the actual phase space sampling, we assume a Poisson distribution
and extract the mean number of gluon emissions in different rapidity
bins and fit the results to a linear function in $\Delta y_{j_f j_b}$,
finding a coefficient of $0.975$ for the inclusive production of a Higgs
boson with two jets. Here are the observed and fitted average gluon
multiplicities as a function of $\Delta y_{j_f j_b}$:
\begin{center}
\includegraphics[width=.75\textwidth]{ng_mean}
\end{center}
As shown for two rapidity slices the assumption of a Poisson
distribution is also a good approximation:
\begin{center}
\includegraphics[width=.49\textwidth]{{ng_1.5}.pdf}\hfill
\includegraphics[width=.49\textwidth]{{ng_5.5}.pdf}
\end{center}
\subsubsection{Number of Gluons inside Jets}
\label{sec:psp_ng_jet}
For each of the $n_g$ gluon emissions we can split the phase-space
integral into a (disconnected) region inside the jets and a remainder:
\begin{equation}
\label{eq:psp_split}
\int [\mathrm{d}p_i] = \int [\mathrm{d}p_i]\,
\theta\bigg(\sum_{j=1}^{m}{\cal J}_j(p_i)\bigg) + \int [\mathrm{d}p_i]\,
\bigg[1-\theta\bigg(\sum_{j=1}^{m}{\cal J}_j(p_i)\bigg)\bigg]\,.
\end{equation}
The next step is to decide how many of the gluons will form part of a
jet. This is done in the \lstinline!PhaseSpacePoint::sample_ng_jets!
function.
We choose an importance sampling which is flat in the plane
spanned by the azimuthal angle $\phi$ and the rapidity $y$. This is
observed in BFKL and valid in the limit of Multi-Regge-Kinematics
(MRK). Furthermore, we assume anti-$k_t$ jets, which cover an area of
$\pi R^2$.
In principle, the total accessible area in the $y$-$\phi$ plane is given
by $2\pi \Delta y_{fb}$, where $\Delta y_{fb}\geq \Delta y_{j_f j_b}$ is
the a priori unknown rapidity separation between the most forward and
backward partons. In most cases the extremal jets consist of single
partons, so that $\Delta y_{fb} = \Delta y_{j_f j_b}$. For the less common
case of two partons forming a jet we observe a maximum distance of $R$
between the constituents and the jet centre. In rare cases jets have
more than two constituents. Empirically, they are always within a
distance of $\tfrac{5}{3}R$ to the centre of the jet, so
$\Delta y_{fb} \leq \Delta y_{j_f j_b} + \tfrac{10}{3} R$. In practice, the
extremal partons are required to carry a large fraction of the jet
transverse momentum and will therefore be much closer to the jet axis.
In summary, for sufficiently large rapidity separations we can use the
approximation $\Delta y_{fb} \approx \Delta y_{j_f j_b}$. This scenario
is depicted here:
\begin{center}
\includegraphics[width=0.5\linewidth]{ps_large_y}
\end{center}
If there is no overlap between jets, the probability $p_{\cal J, >}$ for
an extra gluon to end up inside a jet is then given by
\begin{equation}
\label{eq:p_J_large}
p_{\cal J, >} = \frac{(m - 1)\*R^2}{2\Delta y_{j_f j_b}}\,.
\end{equation}
For a very small rapidity separation, eq.~\eqref{eq:p_J_large}
obviously overestimates the true probability. The maximum phase space
covered by jets in the limit of a vanishing rapidity distance between
all partons is $2mR \Delta y_{fb}$:
\begin{center}
\includegraphics[width=0.5\linewidth]{ps_small_y}
\end{center}
We therefore estimate the probability for a parton to end up inside a jet as
\begin{equation}
\label{eq:p_J}
p_{\cal J} = \min\bigg(\frac{(m - 1)\*R^2}{2\Delta y_{j_f j_b}}, \frac{mR}{\pi}\bigg)\,.
\end{equation}
Here we compare this estimate with the actually observed
fraction of additional emissions into jets as a function of the rapidity
separation:
\begin{center}
\includegraphics[width=0.75\linewidth]{pJ}
\end{center}
\subsubsection{Gluons outside Jets}
\label{sec:gluons_nonjet}
Using our estimate for the probability of a gluon to be a jet
constituent, we choose a number $n_{g,{\cal J}}$ of gluons inside
jets, which also fixes the number $n_g - n_{g,{\cal J}}$ of gluons
outside jets. As explained later on, we need to generate the momenta of
the gluons outside jets first. This is done in
\lstinline!PhaseSpacePoint::gen_non_jet!.
The azimuthal angle $\phi$ is generated flat within $0\leq \phi \leq 2
\pi$. The allowed rapidity interval is set by the most forward and
backward partons, which are necessarily inside jets. Since these parton
rapidities are not known at this point, we also have to postpone the
rapidity generation for the gluons outside jets. For the scalar
transverse momentum $p_\perp = |\mathbf{p}_\perp|$ of a gluon outside
jets we use the parametrisation
\begin{equation}
\label{eq:p_nonjet}
p_\perp = \lambda + \tilde{p}_\perp\*\tan(\tau\*r)\,, \qquad
\tau = \arctan\bigg(\frac{p_{\perp{\cal J}_\text{min}} - \lambda}{\tilde{p}_\perp}\bigg)\,.
\end{equation}
For $r \in [0,1)$, $p_\perp$ is always less than the minimum momentum
$p_{\perp{\cal J}_\text{min}}$ required for a jet. $\tilde{p}_\perp$ is
a free parameter, a good empirical value is $\tilde{p}_\perp = [1.3 +
0.2\*(n_g - n_{g,\cal J})]\,$GeV
\subsubsection{Resummation jet momenta}
\label{sec:ptj_res}
On the one hand, each jet momentum is given by the sum of its
constituent momenta. On the other hand, the resummation jet momenta are
fixed by the constraints in line five of the master
equation~\eqref{eq:resumdijetFKLmatched2}. We therefore have to
calculate the resummation jet momenta from these constraints before
generating the momenta of the gluons inside jets. This is done in
\lstinline!PhaseSpacePoint::reshuffle! and in the free
\lstinline!resummation_jet_momenta! function (declared in \texttt{resummation\_jet.hh}).
The resummation jet momenta are determined by the $\delta$ functions in
line five of eq.~(\ref{eq:resumdijetFKLmatched2}). The rapidities are
fixed to the rapidities of the jets in the input fixed-order events, so
that the FKL ordering is guaranteed to be preserved.
In traditional \HEJ reshuffling the transverse momentum are given through
\begin{equation}
\label{eq:ptreassign_old}
\mathbf{p}^B_{\mathcal{J}_{l\perp}} = \mathbf{j}_{l\perp} \equiv \mathbf{p}_{\mathcal{J}_{l}\perp}
+ \mathbf{q}_\perp \,\frac{|\mathbf{p}_{\mathcal{J}_{l}\perp}|}{P_\perp},
\end{equation}
where $\mathbf{q}_\perp = \sum_{j=1}^n \mathbf{p}_{i\perp}
\bigg[1-\theta\bigg(\sum_{j=1}^{m}{\cal J}_j(p_i)\bigg)\bigg] $ is the
total transverse momentum of all partons \emph{outside} jets and
$P_\perp = \sum_{j=1}^m |\mathbf{p}_{\mathcal{J}_{j}\perp}|$. Since the
total transverse momentum of an event vanishes, we can also use
$\mathbf{q}_\perp = - \sum_{j=1}^m
\mathbf{p}_{\mathcal{J}_{j}\perp}$. Eq.~(\ref{eq:ptreassign}) is a
non-linear system of equations in the resummation jet momenta
$\mathbf{p}_{\mathcal{J}_{l}\perp}$. Hence we would have to solve
\begin{equation}
\label{eq:ptreassign_eq}
\mathbf{p}_{\mathcal{J}_{l}\perp}=\mathbf{j}^B_{l\perp} \equiv\mathbf{j}_{l\perp}^{-1}
\left(\mathbf{p}^B_{\mathcal{J}_{l\perp}}\right)
\end{equation}
numerically.
Since solving such a system is computationally expensive, we instead
change the reshuffling around to be linear in the resummation jet
momenta. Hence~\eqref{eq:ptreassign_eq} gets replaces by
\begin{equation}
\label{eq:ptreassign}
\mathbf{p}_{\mathcal{J}_{l\perp}} = \mathbf{j}^B_{l\perp} \equiv \mathbf{p}^B_{\mathcal{J}_{l}\perp}
- \mathbf{q}_\perp \,\frac{|\mathbf{p}^B_{\mathcal{J}_{l}\perp}|}{P^B_\perp},
\end{equation}
which is linear in the resummation momentum. Consequently the equivalent
of~\eqref{eq:ptreassign_old} is non-linear in the Born momentum. However
the exact form of~\eqref{eq:ptreassign_old} is not relevant for the resummation.
Both methods have been tested for two and three jets with the \textsc{rivet}
standard analysis \texttt{MC\_JETS}. They didn't show any differences even
after $10^9$ events.
The reshuffling relation~\eqref{eq:ptreassign} allows the transverse
momenta $p^B_{\mathcal{J}_{l\perp}}$ of the fixed-order jets to be
somewhat below the minimum transverse momentum of resummation jets. It
is crucial that this difference does not become too large, as the
fixed-order cross section diverges for vanishing transverse momenta. In
the production of a Higgs boson with resummation jets above $30\,$GeV we observe
that the contribution from fixed-order events with jets softer than
about $20\,$GeV can be safely neglected. This is shown in the following
plot of the differential cross section over the transverse momentum of
the softest fixed-order jet:
\begin{center}
\includegraphics[width=.75\textwidth]{ptBMin}
\end{center}
Finally, we have to account for the fact that the reshuffling
relation~\eqref{eq:ptreassign} is non-linear in the Born momenta. To
arrive at the master formula~\eqref{eq:resumdijetFKLmatched2} for the
cross section, we have introduced unity in the form of an integral over
the Born momenta with $\delta$ functions in the integrand, that is
\begin{equation}
\label{eq:delta_intro}
1 = \int_{p_{j\perp}^B=0}^{p_{j\perp}^B=\infty}
\mathrm{d}^2\mathbf{p}_{j\perp}^B\delta^{(2)}(\mathbf{p}_{\mathcal{J}_{j\perp}}^B -
\mathbf{j}_{j\perp})\,.
\end{equation}
If the arguments of the $\delta$ functions are not linear in the Born
momenta, we have to compensate with additional Jacobians as
factors. Explicitly, for the reshuffling relation~\eqref{eq:ptreassign}
we have
\begin{equation}
\label{eq:delta_rewrite}
\prod_{l=1}^m \delta^{(2)}(\mathbf{p}_{\mathcal{J}_{l\perp}}^B -
\mathbf{j}_{l\perp}) = \Delta \prod_{l=1}^m \delta^{(2)}(\mathbf{p}_{\mathcal{J}_{l\perp}} -
\mathbf{j}_{l\perp}^B)\,,
\end{equation}
where $\mathbf{j}_{l\perp}^B$ is given by~\eqref{eq:ptreassign_eq} and only
depends on the Born momenta. We have extended the product to run to $m$
instead of $m-1$ by eliminating the last $\delta$ function
$\delta^{(2)}\!\!\left(\sum_{k=1}^n \mathbf{p}_{k\perp}\right )$.
The Jacobian $\Delta$ is the determinant of a $2m \times 2m$ matrix with $l, l' = 1,\dots,m$
and $X, X' = x,y$.
\begin{equation}
\label{eq:jacobian}
\Delta = \left|\frac{\partial\,\mathbf{j}^B_{l'\perp}}{\partial\, \mathbf{p}^B_{{\cal J}_l \perp}} \right|
= \left| \delta_{l l'} \delta_{X X'} - \frac{q_X\, p^B_{{\cal
J}_{l'}X'}}{\left|\mathbf{p}^B_{{\cal J}_{l'} \perp}\right| P^B_\perp}\left(\delta_{l l'}
- \frac{\left|\mathbf{p}^B_{{\cal J}_l \perp}\right|}{P^B_\perp}\right)\right|\,.
\end{equation}
The determinant is calculated in \lstinline!resummation_jet_weight!,
again coming from the \texttt{resummation\_jet.hh} header.
Having to introduce this Jacobian is not a disadvantage specific to the new
reshuffling. If we instead use the old reshuffling
relation~\eqref{eq:ptreassign_old} we \emph{also} have to introduce a
similar Jacobian since we actually want to integrate over the
resummation phase space and need to transform the argument of the
$\delta$ function to be linear in the resummation momenta for this.
\subsubsection{Gluons inside Jets}
\label{sec:gluons_jet}
After the steps outlined in section~\ref{sec:psp_ng_jet}, we have a
total number of $m + n_{g,{\cal J}}$ constituents. In
\lstinline!PhaseSpacePoint::distribute_jet_partons! we distribute them
randomly among the jets such that each jet has at least one
constituent. We then generate their momenta in
\lstinline!PhaseSpacePoint::split! using the \lstinline!Splitter! class.
The phase space integral for a jet ${\cal J}$ is given by
\begin{equation}
\label{eq:ps_jetparton} \prod_{i\text{ in }{\cal J}} \bigg(\int
\mathrm{d}\mathbf{p}_{i\perp}\ \int \mathrm{d} y_i
\bigg)\delta^{(2)}\Big(\sum_{i\text{ in }{\cal J}} \mathbf{p}_{i\perp} -
\mathbf{j}_{\perp}^B\Big)\delta(y_{\mathcal{J}}-y^B_{\mathcal{J}})\,.
\end{equation}
For jets with a single constituent, the parton momentum is obiously equal to the
jet momentum. In the case of two constituents, we observe that the
partons are always inside the jet cone with radius $R$ and often very
close to the jet centre. The following plots show the typical relative
distance $\Delta R/R$ for this scenario:
\begin{center}
\includegraphics[width=0.45\linewidth]{dR_2}
\includegraphics[width=0.45\linewidth]{dR_2_small}
\end{center}
According to this preference for small values of $\Delta R$, we
parametrise the $\Delta R$ integrals as
\begin{equation}
\label{eq:dR_sampling}
\frac{\Delta R}{R} =
\begin{cases}
0.25\,x_R & x_R < 0.4 \\
1.5\,x_R - 0.5 & x_R \geq 0.4
\end{cases}\,.
\end{equation}
Next, we generate $\Theta_1 \equiv \Theta$ and use the constraint $\Theta_2 = \Theta
\pm \pi$. The transverse momentum of the first parton is then given by
\begin{equation}
\label{eq:delta_constraints}
p_{1\perp} =
\frac{p_{\mathcal{J} y} - \tan(\phi_2) p_{\mathcal{J} x}}{\sin(\phi_1)
- \tan(\phi_2)\cos(\phi_1)}\,.
\end{equation}
We get $p_{2\perp}$ by exchanging $1 \leftrightarrow 2$ in the
indices. To obtain the Jacobian of the transformation, we start from the
single jet phase space eq.~(\ref{eq:ps_jetparton}) with the rapidity
delta function already rewritten to be linear in the rapidity of the
last parton, i.e.
\begin{equation}
\label{eq:jet_2p}
\prod_{i=1,2} \bigg(\int
\mathrm{d}\mathbf{p}_{i\perp}\ \int \mathrm{d} y_i
\bigg)\delta^{(2)}\Big(\mathbf{p}_{1\perp} + \mathbf{p}_{2\perp} -
\mathbf{j}_{\perp}^B\Big)\delta(y_2- \dots)\,.
\end{equation}
The integral over the second parton momentum is now trivial; we can just replace
the integral over $y_2$ with the equivalent constraint
\begin{equation}
\label{eq:R2}
\int \mathrm{d}R_2 \ \delta\bigg(R_2 - \bigg[\phi_{\cal J} - \arctan
\bigg(\frac{p_{{\cal J}y} - p_{1y}}{p_{{\cal J}x} -
p_{1x}}\bigg)\bigg]/\cos \Theta\bigg) \,.
\end{equation}
In order to fix the integral over $p_{1\perp}$ instead, we rewrite this
$\delta$ function. This introduces the Jacobian
\begin{equation}
\label{eq:jac_pt1}
\bigg|\frac{\partial p_{1\perp}}{\partial R_2} \bigg| =
\frac{\cos(\Theta)\mathbf{p}_{2\perp}^2}{p_{{\cal J}\perp}\sin(\phi_{\cal J}-\phi_1)}\,.
\end{equation}
The final form of the integral over the two parton momenta is then
\begin{equation}
\label{eq:ps_jet_2p}
\int \mathrm{d}R_1\ R_1 \int \mathrm{d}R_2 \int \mathrm{d}x_\Theta\ 2\pi \int
\mathrm{d}p_{1\perp}\ p_{1\perp} \int \mathrm{d}p_{2\perp}
\ \bigg|\frac{\partial p_{1\perp}}{\partial R_2} \bigg|\delta(p_{1\perp}
-\dots) \delta(p_{2\perp} - \dots)\,.
\end{equation}
As is evident from section~\ref{sec:psp_ng_jet}, jets with three or more
constituents are rare and an efficient phase-space sampling is less
important. For such jets, we exploit the observation that partons with a
distance larger than $R_{\text{max}} = \tfrac{5}{3} R$ to
the jet centre are never clustered into the jet. Assuming $N$
constituents, we generate all components
for the first $N-1$ partons and fix the remaining parton with the
$\delta$-functional. In order to end up inside the jet, we use the
parametrisation
\begin{align}
\label{eq:ps_jet_param}
\phi_i ={}& \phi_{\cal J} + \Delta \phi_i\,, & \Delta \phi_i ={}& \Delta
R_i
\cos(\Theta_i)\,, \\
y_i ={}& y_{\cal J} + \Delta y_i\,, & \Delta y_i ={}& \Delta
R_i
\sin(\Theta_i)\,,
\end{align}
and generate $\Theta_i$ and $\Delta R_i$ randomly with $\Delta R_i \leq
R_{\text{max}}$ and the empiric value $R_{\text{max}} = 5\*R/3$. We can
then write the phase space integral for a single parton as $(p_\perp = |\mathbf{p}_\perp|)$
\begin{equation}
\label{eq:ps_jetparton_x}
\int \mathrm{d}\mathbf{p}_{\perp}\ \int
\mathrm{d} y \approx \int_{\Box} \mathrm{d}x_{\perp}
\mathrm{d}x_{ R}
\mathrm{d}x_{\theta}\
2\*\pi\,\*R_{\text{max}}^2\,\*x_{R}\,\*p_{\perp}\,\*(p_{\perp,\text{max}}
- p_{\perp,\text{min}})
\end{equation}
with
\begin{align}
\label{eq:ps_jetparton_parameters}
\Delta \phi ={}& R_{\text{max}}\*x_{R}\*\cos(2\*\pi\*x_\theta)\,,&
\Delta y ={}& R_{\text{max}}\*x_{R}\*\sin(2\*\pi\*x_\theta)\,, \\
p_{\perp} ={}& (p_{\perp,\text{max}} - p_{\perp,\text{min}})\*x_\perp +
p_{\perp,\text{min}}\,.
\end{align}
$p_{\perp,\text{max}}$ is determined from the requirement that the total
contribution from the first $n-1$ partons --- i.e. the projection onto the
jet $p_{\perp}$ axis --- must never exceed the jet $p_\perp$. This gives
\todo{This bound is too high}
\begin{equation}
\label{eq:pt_max}
p_{i\perp,\text{max}} = \frac{p_{{\cal J}\perp} - \sum_{j<i} p_{j\perp}
\cos \Delta
\phi_j}{\cos \Delta
\phi_i}\,.
\end{equation}
The $x$ and $y$ components of the last parton follow immediately from
the first $\delta$ function. The last rapidity is fixed by the condition that
the jet rapidity is kept fixed by the reshuffling, i.e.
\begin{equation}
\label{eq:yJ_delta}
y^B_{\cal J} = y_{\cal J} = \frac 1 2 \ln \frac{\sum_{i=1}^n E_i+ p_{iz}}{\sum_{i=1}^n E_i - p_{iz}}\,.
\end{equation}
With $E_n \pm p_{nz} = p_{n\perp}\exp(\pm y_n)$ this can be rewritten to
\begin{equation}
\label{eq:yn_quad_eq}
\exp(2y_{\cal J}) = \frac{\sum_{i=1}^{n-1} E_i+ p_{iz}+p_{n\perp} \exp(y_n)}{\sum_{i=1}^{n-1} E_i - p_{iz}+p_{n\perp} \exp(-y_n)}\,,
\end{equation}
which is a quadratic equation in $\exp(y_n)$. The physical solution is
\begin{align}
\label{eq:yn}
y_n ={}& \log\Big(-b + \sqrt{b^2 + \exp(2y_{\cal J})}\,\Big)\,,\\
b ={}& \bigg(\sum_{i=1}^{n-1} E_i + p_{iz} - \exp(2y_{\cal J})
\sum_{i=1}^{n-1} E_i - p_{iz}\bigg)/(2 p_{n\perp})\,.
\end{align}
\todo{what's wrong with the following?} To eliminate the remaining rapidity
integral, we transform the $\delta$ function to be linear in the
rapidity $y$ of the last parton. The corresponding Jacobian is
\begin{equation}
\label{eq:jacobian_y}
\bigg|\frac{\partial y_{\cal J}}{\partial y_n}\bigg|^{-1} = 2 \bigg( \frac{E_n +
p_{nz}}{E_{\cal J} + p_{{\cal J}z}} + \frac{E_n - p_{nz}}{E_{\cal J} -
p_{{\cal J}z}}\bigg)^{-1}\,.
\end{equation}
Finally, we check that all designated constituents are actually
clustered into the considered jet.
\subsubsection{Final steps}
\label{sec:final}
Knowing the rapidity span covered by the extremal partons, we can now
generate the rapdities for the partons outside jets. We perform jet
clustering on all partons and check in
\lstinline!PhaseSpacePoint::jets_ok! that all the following criteria are
fulfilled:
\begin{itemize}
\item The number of resummation jets must match the number of
fixed-order jets.
\item No partons designated to be outside jets may end up inside jets.
\item All other outgoing partons \emph{must} end up inside jets.
\item The extremal (in rapidity) partons must be inside the extremal
jets. If there is, for example, an unordered forward emission, the
most forward parton must end up inside the most forward jet and the
next parton must end up inside second jet.
\item The rapidities of fixed-order and resummation jets must match.
\end{itemize}
After this, we adjust the phase-space normalisation according to the
third line of eq.~(\ref{eq:resumdijetFKLmatched2}), determine the
flavours of the outgoing partons, and adopt any additional colourless
bosons from the fixed-order input event. Finally, we use momentum
conservation to reconstruct the momenta of the incoming partons.
+\subsection{Colour connection}
+\label{sec:Colour}
+
+\begin{figure}
+ \input{src/ColourConnect.tex}
+ \caption{Left: Non-crossing colour flow dominating in the MRK limit. The
+ crossing of the colour line connecting to particle 2 can be resolved by
+ writing particle 2 on the left. Right: A colour flow with a (manifest)
+ colour-crossing. The crossing can only be resolved if one breaks the
+ rapidities order, e.g. switching particles 2 and 3. From~\cite{Andersen:2017sht}.}
+ \label{fig:Colour_crossing}
+\end{figure}
+
+After the phase space for the resummation event is generated, we can construct
+the colour for each particle. To generate the colour flow one has to call
+\lstinline!Event::generate_colours! on any \HEJ configuration. For non-\HEJ
+event we do not change the colour, and assume it is provided by the user (e.g.
+through the LHE file input). The colour connection is done in the large $N_c$
+(infinite number of colour) limit with leading colour in
+MRK~\cite{Andersen:2008ue, Andersen:2017sht}. The idea is to allow only
+$t$-channel colour exchange, without any crossing colour lines. For example the
+colour crossing in the colour connection on the left of
+figure~\ref{fig:Colour_crossing} can be resolved by switching \textit{particle
+2} to the left.
+
+We can write down the colour connections by following the colour flow from
+\textit{gluon a} to \textit{gluon b} and back to \textit{gluon a}, e.g.
+figure~\ref{fig:Colour_gleft} corresponds to $a123ba$. In such an expression any
+valid, non-crossing colour flow will connect all external legs while respecting
+the rapidity ordering. Thus configurations like the left of
+figure~\ref{fig:Colour_crossing} are allowed ($a134b2a$), but the right of the
+same figures breaks the rapidity ordering between 2 and 3 ($a1324ba$). Note that
+connections between $b$ and $a$ are in inverse order, e.g. $ab321a$ corresponds to~\ref{fig:Colour_gright} ($a123ba$) just with colour and anti-colour swapped.
+
+\begin{figure}
+\centering
+\subcaptionbox{$a123ba$\label{fig:Colour_gright}}{
+ \includegraphics[height=0.25\textwidth]{figures/colour_gright.jpg}}
+\subcaptionbox{$a13b2a$\label{fig:Colour_gleft}}{
+ \includegraphics[height=0.25\textwidth]{figures/colour_gleft.jpg}}
+\subcaptionbox{$a\_123ba$\label{fig:Colour_qx}}{
+ \includegraphics[height=0.25\textwidth]{figures/colour_qx.jpg}}
+\subcaptionbox{$a\_23b1a$\label{fig:Colour_uno}}{
+ \includegraphics[height=0.25\textwidth]{figures/colour_uno.jpg}}
+\subcaptionbox{$a14b3\_2a$\label{fig:Colour_qqx}}{
+ \includegraphics[height=0.25\textwidth]{figures/colour_centralqqx.jpg}}
+\caption{Different colour non-crossing colour connections. Both incoming
+ particles are drawn at the top or bottom and the outgoing left or right.
+ The Feynman diagram is shown in black and the colour flow in blue.}
+ %TODO Maybe make these plots nicer (in Latex/asy)
+\end{figure}
+
+If we replace two gluons with a quark, (anti-)quark pair we break one of the
+colour connections. Still the basic concept from before holds, we just have to
+treat the connection between two (anti-)quarks like an unmovable (anti-)colour.
+We denote such a connection by a underscore (e.g. $1\_a$). For example the
+equivalent of~\ref{fig:Colour_gright} ($a123ba$) with an incoming antiquark
+is~\ref{fig:Colour_qx} ($a\_123ba$). As said this also holds for other
+subleading configurations like unordered emission~\ref{fig:Colour_uno} or
+central quark-antiquark pairs~\ref{fig:Colour_qqx} \footnote{Obviously this can
+not be guaranteed for non-\HEJ configurations, e.g. $qQ\to Qq$ requires a
+$u$-channel exchange.}.
+
+Some rapidity ordering can have multiple possible colour connections,
+e.g.~\ref{fig:Colour_gright} and~\ref{fig:Colour_gleft}. This is always the case
+if a gluon radiates off a gluon line. In that case we randomly connect the gluon
+to either the colour or anti-colour. Thus in the generation we keep track
+whether we are on a quark or gluon line, and act accordingly.
+
+
+
\subsection{The matrix element }
\label{sec:ME}
The derivation of the \HEJ matrix element is explained in some detail
in~\cite{Andersen:2017kfc}, where also results for leading and
subleading matrix elements for pure multijet production and production
of a Higgs boson with at least two associated jets are listed. Matrix
elements for $W$ and $Z/\gamma^*$ production together with jets are
given in~\cite{Andersen:2012gk,Andersen:2016vkp}, but not yet included.
The matrix elements are implemented in the \lstinline!MatrixElement!
class. To discuss the structure, let us consider the squared matrix
element for FKL multijet production with $n$ final-state partons:
\begin{align}
\label{eq:ME}
\begin{split}
\overline{\left|\mathcal{M}_\text{HEJ}^{f_1 f_2 \to f_1
g\cdots g f_2}\right|}^2 = \ &\frac {(4\pi\alpha_s)^n} {4\ (N_c^2-1)}
\cdot\ \textcolor{blue}{\frac {K_{f_1}(p_1^-, p_a^-)} {t_1}\ \cdot\ \frac{K_{f_2}(p_n^+, p_b^+)}{t_{n-1}}\ \cdot\ \left\|S_{f_1 f_2\to f_1 f_2}\right\|^2}\\
& \cdot \prod_{i=1}^{n-2} \textcolor{gray}{\left( \frac{-C_A}{t_it_{i+1}}\
V^\mu(q_i,q_{i+1})V_\mu(q_i,q_{i+1}) \right)}\\
& \cdot \prod_{j=1}^{n-1} \textcolor{red}{\exp\left[\omega^0(q_{j\perp})(y_{j+1}-y_j)\right]}.
\end{split}
\end{align}
The structure and momentum assignment of the unsquared matrix element is
as illustrated here:
\begin{center}
\includegraphics{HEJ_amplitude}
\end{center}
The square
of the complete matrix element as given in eq.~(\ref{eq:ME}) is
calculated by \lstinline!MatrixElement::operator()!. The \textcolor{red}{last line} of
eq.~\eqref{eq:ME} constitutes the all-order virtual correction,
implemented in
\lstinline!MatrixElement::virtual_corrections!.
$\omega^0$ is the
\textit{regularised Regge trajectory}
\begin{equation}
\label{eq:omega_0}
\omega^0(q_\perp) = - C_A \frac{\alpha_s}{\pi} \log \left(\frac{q_\perp^2}{\lambda^2}\right)\,,
\end{equation}
where $\lambda$ is the slicing parameter limiting the softness of real
gluon emissions, cf. eq.~(\ref{eq:resumdijetFKLmatched2}).
The remaining parts, which correspond to the square of the leading-order
HEJ matrix element $\overline{\left|\mathcal{M}_\text{LO,
HEJ}^{f_1f_2\to f_1g\cdots
gf_2}\big(\big\{p^B_j\big\}\big)\right|}^{2}$, are computed in
\lstinline!MatrixElement::tree!. We can further factor off the
scale-dependent ``parametric'' part
\lstinline!MatrixElement::tree_param! containing all factors of the
strong coupling $4\pi\alpha_s$. Using this function saves some CPU time
when adjusting the renormalisation scale, see
section~\ref{sec:resum}. The remaining ``kinematic'' factors are
calculated in \lstinline!MatrixElement::kin!.
\subsubsection{Matrix elements for Higgs plus dijet}
\label{sec:ME_h_jets}
In the production of a Higgs boson together with jets the parametric
parts and the virtual corrections only require minor changes in the
respective functions. However, in the ``kinematic'' parts we have to
distinguish between several cases, which is done in
\lstinline!MatrixElement::tree_kin_Higgs!. The Higgs boson can be
\emph{central}, i.e. inside the rapidity range spanned by the extremal
partons (\lstinline!MatrixElement::tree_kin_Higgs_central!) or
\emph{peripheral} and outside this range
(\lstinline!MatrixElement::tree_kin_Higgs_first! or
\lstinline!MatrixElement::tree_kin_Higgs_last!). In case there is also
an unordered gluon emission the matrix element is already suppressed by one
logarithm $\log(s/t)$. Therefore at NLL the Higgs boson can only be emitted
centrally\footnote{In principle emitting a Higgs boson \textit{on the other
side} of the unordered gluon is possible by contracting an unordered and
external Higgs current. Obviously this would not cover all possible
configurations, e.g. $qQ\to HgqQ$ requires contraction of the standard $Q\to Q$
current with an (unknown) $q\to Hgq$ one.}.
If a Higgs boson with momentum $p_H$ is emitted centrally, after parton
$j$ in rapidity, the matrix element reads
\begin{equation}
\label{eq:ME_h_jets_central}
\begin{split}
\overline{\left|\mathcal{M}_\text{HEJ}^{f_1 f_2 \to f_1 g\cdot H
\cdot g f_2}\right|}^2 = \ &\frac {\alpha_s^2 (4\pi\alpha_s)^n} {4\ (N_c^2-1)}
\cdot\ \textcolor{blue}{\frac {K_{f_1}(p_1^-, p_a^-)} {t_1}\
\cdot\ \frac{1}{t_j t_{j+1}} \cdot\ \frac{K_{f_2}(p_n^+, p_b^+)}{t_{n}}\ \cdot\ \left\|S_{f_1
f_2\to f_1 H f_2}\right\|^2}\\
& \cdot \prod_{\substack{i=1\\i \neq j}}^{n-1} \textcolor{gray}{\left( \frac{-C_A}{t_it_{i+1}}\
V^\mu(q_i,q_{i+1})V_\mu(q_i,q_{i+1}) \right)}\\
& \cdot \textcolor{red}{\prod_{i=1}^{n-1}
\exp\left[\omega^0(q_{i\perp})\Delta y_i\right]}
\end{split}
\end{equation}
with the momentum definitions
\begin{center}
\includegraphics{HEJ_central_Higgs_amplitude}
\end{center}
$q_i$ is the $i$th $t$-channel momentum and $\Delta y_i$ the rapidity
gap between outgoing \emph{particles} (not partons) $i$ and $i+1$ in
rapidity ordering.
For \emph{peripheral} emission in the backward direction
(\lstinline!MatrixElement::tree_kin_Higgs_first!) we first check whether
the most backward parton is a gluon or an (anti-)quark. In the latter
case the leading contribution to the matrix element arises through
emission off the $t$-channel gluons and we can use the same formula
eq.~(\ref{eq:ME_h_jets_central}) as for central emission. If the most
backward parton is a gluon, the square of the matrix element can be
written as
\begin{equation}
\label{eq:ME_h_jets_peripheral}
\begin{split}
\overline{\left|\mathcal{M}_\text{HEJ}^{g f_2 \to H g\cdot g f_2}\right|}^2 = \ &\frac {\alpha_s^2 (4\pi\alpha_s)^n} {\textcolor{blue}{4\ (N_c^2-1)}}
\textcolor{blue}{\cdot\ K_{H}\
\frac{K_{f_2}(p_n^+, p_b^+)}{t_{n-1}}\ \cdot\ \left\|S_{g
f_2\to H g f_2}\right\|^2}\\
& \cdot \prod_{\substack{i=1}}^{n-2} \textcolor{gray}{\left( \frac{-C_A}{t_it_{i+1}}\
V^\mu(q_i,q_{i+1})V_\mu(q_i,q_{i+1}) \right)}\\
& \cdot \textcolor{red}{\prod_{i=1}^{n-1}
\exp\left[\omega^0(q_{i\perp}) (y_{i+1} - y_i)\right]}
\end{split}
\end{equation}
with the momenta as follows:
\begin{center}
\includegraphics{HEJ_peripheral_Higgs_amplitude}
\end{center}
The \textcolor{blue}{blue part} is implemented in
\lstinline!MatrixElement::MH2_forwardH!. All other building blocks are
already available.\todo{Impact factors} The actual current contraction
is calculated in \lstinline!MH2gq_outsideH! inside
\lstinline!currents.cc!, which corresponds to $\tfrac{16 \pi^2}{t_1} \left\|S_{g
f_2\to H g f_2}\right\|^2$.\todo{Fix this insane normalisation}
The forward emission of a Higgs boson is completely analogous. We can
use the same function \lstinline!MatrixElement::MH2_forwardH!, swapping
$p_1 \leftrightarrow p_n,\,p_a \leftrightarrow p_b$.
\subsubsection{FKL ladder and Lipatov vertices}
\label{sec:FKL_ladder}
The ``FKL ladder'' is the product
\begin{equation}
\label{eq:FKL_ladder}
\prod_{i=1}^{n-2} \left( \frac{-C_A}{t_it_{i+1}}\
V^\mu(q_i,q_{i+1})V_\mu(q_i,q_{i+1}) \right)
\end{equation}
appearing in the square of the matrix element for $n$ parton production,
cf. eq.~(\ref{eq:ME}), and implemented in
\lstinline!MatrixElement::FKL_ladder_weight!. The Lipatov vertex contraction
$V^\mu(q_i,q_{i+1})V_\mu(q_i,q_{i+1})$ is implemented \lstinline!C2Lipatovots!.
It is given by \todo{equation} \todo{mention difference between the two versions
of \lstinline!C2Lipatovots!, maybe even get rid of one}.
\subsubsection{Currents}
\label{sec:currents}
The current factors $\frac{K_{f_1}K_{f_2}}{t_1 t_{n-1}}\left\|S_{f_1
f_2\to f_1 f_2}\right\|^2$ and their extensions for unordered and Higgs
boson emissions are implemented in the \lstinline!jM2!$\dots$ functions
of \texttt{src/currents.cc}. \todo{Only $\|S\|^2$ should be in currents}
\footnote{The current implementation for
Higgs production in \texttt{src/currents.cc} includes the $1/4$ factor
inside $S$, opposing to~\eqref{eq:ME}. Thus the overall normalisation is
unaffected.} The ``colour acceleration multiplier'' (CAM) $K_{f}$
for a parton $f\in\{g,q,\bar{q}\}$ is defined as
\begin{align}
\label{eq:K_g}
K_g(p_1^-, p_a^-) ={}& \frac{1}{2}\left(\frac{p_1^-}{p_a^-} + \frac{p_a^-}{p_1^-}\right)\left(C_A -
\frac{1}{C_A}\right)+\frac{1}{C_A}\\
\label{eq:K_q}
K_q(p_1^-, p_a^-) ={}&K_{\bar{q}}(p_1^-, p_a^-) = C_F\,.
\end{align}
The Higgs current CAM used in eq.~(\ref{eq:ME_h_jets_peripheral}) is
\begin{equation}
\label{eq:K_H}
K_H = C_A\,.
\end{equation}
The current contractions are given by\todo{check all this
carefully!}
\begin{align}
\label{eq:S}
\left\|S_{f_1 f_2\to f_1 f_2}\right\|^2 ={}& \sum_{\substack{\lambda_a =
+,-\\\lambda_b = +,-}} \left|j^{\lambda_a}_\mu(p_1, p_a)\
j^{\lambda_b\,\mu}(p_n, p_b)\right|^2 = 2\sum_{\lambda =
+,-} \left|j^{-}_\mu(p_1, p_a)\ j^{\lambda\,\mu}(p_n, p_b)\right|^2\,,\\
\left\|S_{f_1 f_2\to f_1 H f_2}\right\|^2 ={}& \sum_{\substack{\lambda_a =
+,-\\\lambda_b = +,-}} \left|j^{\lambda_a}_\mu(p_1, p_a)V_H^{\mu\nu}(q_j, q_{j+1})\
j^{\lambda_b}_\nu(p_n, p_b)\right|^2\,,\\
\left\|S_{g f_2 \to H g f_2}\right\|^2 ={}& \sum_{
\substack{
\lambda_{a} = +,-\\
\lambda_{1} =+,-\\
\lambda_{b} = +,-
}}
\left|j^{\lambda_a\lambda_1}_{H\,\mu}(p_1, p_a, p_H)\ j^{\lambda_b\,\mu}(p_n, p_b)\right|^2\,.
\end{align}
The ``basic'' currents $j$ are independent of the parton flavour and read
\begin{equation}
\label{eq:j}
j^\pm_\mu(p, q) = u^{\pm,\dagger}(p)\ \sigma^\pm_\mu\ u^{\pm}(q)\,,
\end{equation}
where $\sigma_\mu^\pm = (1, \pm \sigma_i)$ and $\sigma_i$ are the Pauli
matrices
\begin{equation}
\label{eq:Pauli_matrices}
\sigma_1 =
\begin{pmatrix}
0 & 1\\ 1 & 0
\end{pmatrix}
\,,
\qquad \sigma_2 =
\begin{pmatrix}
0 & -i\\ i & 0
\end{pmatrix}
\,,
\qquad \sigma_3 =
\begin{pmatrix}
1 & 0\\ 0 & -1
\end{pmatrix}
\,.
\end{equation}
The two-component chiral spinors are given by
\begin{align}
\label{eq:u_plus}
u^+(p)={}& \left(\sqrt{p^+}, \sqrt{p^-} \hat{p}_\perp \right) \,,\\
\label{eq:u_minus}
u^-(p)={}& \left(\sqrt{p^-} \hat{p}^*_\perp, -\sqrt{p^+}\right)\,,
\end{align}
with $p^\pm = E\pm p_z,\, \hat{p}_\perp = \tfrac{p_\perp}{|p_\perp|},\,
p_\perp = p_x + i p_y$. The spinors for vanishing transverse momentum
are obtained by replacing $\hat{p_\perp} \to -1$.
Explicitly, the currents read
\begin{align}
\label{eq:j-_explicit}
j^-_\mu(p, q) ={}&
\begin{pmatrix}
\sqrt{p^+\,q^+} + \sqrt{p^-\,q^-} \hat{p}_{\perp} \hat{q}_{\perp}^*\\
\sqrt{p^-\,q^+}\, \hat{p}_{\perp} + \sqrt{p^+\,q^-}\,\hat{q}_{\perp}^*\\
-i \sqrt{p^-\,q^+}\, \hat{p}_{\perp} + i \sqrt{p^+\,q^-}\, \hat{q}_{\perp}^*\\
\sqrt{p^+\,q^+} - \sqrt{p^-\,q^-}\, \hat{p}_{\perp}\, \hat{q}_{\perp}^*
\end{pmatrix}\\
j^+_\mu(p, q) ={}&\big(j^-_\mu(p, q)\big)^*
\end{align}
If $q= p_{\text{in}}$ is the momentum of an incoming parton, we have
$\hat{p}_{\text{in} \perp} = -1$ and either $p_{\text{in}}^+ = 0$ or
$p_{\text{in}}^- = 0$. The current simplifies further:\todo{Helicities flipped w.r.t code}
\begin{align}
\label{eq:j_explicit}
j^-_\mu(p_{\text{out}}, p_{\text{in}}) ={}&
\begin{pmatrix}
\sqrt{p_{\text{in}}^+\,p_{\text{out}}^+}\\
\sqrt{p_{\text{in}}^+\,p_{\text{out}}^-} \ \hat{p}_{\text{out}\,\perp}\\
-i\,j^-_1\\
j^-_0
\end{pmatrix}
& p_{\text{in}\,z} > 0\,,\\
j^-_\mu(p_{\text{out}}, p_{\text{in}}) ={}&
\begin{pmatrix}
-\sqrt{p_{\text{in}}^-\,p_{\text{out}}^{-\phantom{+}}} \ \hat{p}_{\text{out}\,\perp}\\
- \sqrt{p_{\text{in}}^-\,p_{\text{out}}^+}\\
i\,j^-_1\\
-j^-_0
\end{pmatrix} & p_{\text{in}\,z} < 0\,.
\end{align}
\section{The fixed-order generator}
\label{sec:HEJFOG}
Even at leading order, standard fixed-order generators can only generate
events with a limited number of final-state particles within reasonable
CPU time. The purpose of the fixed-order generator is to supplement this
with high-multiplicity input events according to the first two lines of
eq.~\eqref{eq:resumdijetFKLmatched2} with the \HEJ approximation
$\mathcal{M}_\text{LO, HEJ}^{f_1f_2\to f_1g\cdots gf_2}$ instead of the
full fixed-order matrix element $\mathcal{M}_\text{LO}^{f_1f_2\to
f_1g\cdots gf_2}$. Its usage is described in the user
documentation \url{https://hej.web.cern.ch/HEJ/doc/current/user/HEJFOG.html}.
\subsection{File structure}
\label{sec:HEJFOG_structure}
The code for the fixed-order generator is in the \texttt{FixedOrderGen}
directory, which contains the following:
\begin{description}
\item[include:] Contains the C++ header files.
\item[src:] Contains the C++ source files.
\item[t:] Contains the source code for the automated tests.
\item[CMakeLists.txt:] Configuration file for the \cmake build system.
\item[configFO.yml:] Sample configuration file for the fixed-order generator.
\end{description}
The code is generally in the \lstinline!HEJFOG! namespace. Functions and
classes \lstinline!MyClass! are usually declared in
\texttt{include/MyClass.hh} and implemented in \texttt{src/MyClass.cc}.
\subsection{Program flow}
\label{sec:prog_flow}
A single run of the fixed-order generator consists of three or four
stages.
First, we perform initialisation similar to HEJ 2, see
section~\ref{sec:init}. Since there is a lot of overlap we frequently
reuse classes and functions from HEJ 2, i.e. from the
\lstinline!HEJ! namespace. The code for parsing the configuration file
is in \texttt{include/config.hh} and implemented in
\texttt{src/config.cc}.
If partial unweighting is requested in the user settings \url{https://hej.web.cern.ch/HEJ/doc/current/user/HEJFOG.html#settings},
the initialisation is followed by a calibration phase. We use a
\lstinline!EventGenerator! to produce a number of trial
events. We use these to calibrate the \lstinline!Unweighter! in
its constructor and produce a first batch of partially unweighted
events. This also allows us to estimate our unweighting efficiency.
In the next step, we continue to generate events and potentially
unweight them. Once the user-defined target number of events is reached,
we adjust their weights according to the number of required trials. As
in HEJ 2 (see section~\ref{sec:processing}), we pass the final
events to a \lstinline!HEJ::Analysis! and a
\lstinline!HEJ::CombinedEventWriter!.
\subsection{Event generation}
\label{sec:evgen}
Event generation is performed by the
\lstinline!EventGenerator::gen_event! member function. We begin by generating a
\lstinline!PhaseSpacePoint!. This is not to be confused with
the resummation phase space points represented by
\lstinline!HEJ::PhaseSpacePoint!! After jet clustering, we compute the
leading-order matrix element (see section~\ref{sec:ME}) and pdf factors.
The phase space point generation is performed in the
\lstinline!PhaseSpacePoint! constructor. We first construct the
user-defined number of $n_p$ partons (by default gluons) in
\lstinline!PhaseSpacePoint::gen_LO_partons!. We use flat sampling in
rapidity and azimuthal angle. For the scalar transverse momenta, we
distinguish between two cases. By default, they are generated based on a
random variable $x_{p_\perp}$ according to
\begin{equation}
\label{eq:pt_sampling}
p_\perp = p_{\perp,\text{min}} +
\begin{cases}
p_{\perp,\text{par}}
\tan\left(
x_{p_\perp}
\arctan\left(
\frac{p_{\perp,\text{max}} - p_{\perp,\text{min}}}{p_{\perp,\text{par}}}
\right)
\right)
& y < y_\text{cut}
\\
- \tilde{p}_{\perp,\text{par}}\log\left(1 - x_{p_\perp}\left[1 -
\exp\left(\frac{p_{\perp,\text{min}} -
p_{\perp,\text{max}}}{\tilde{p}_{\perp,\text{par}}}\right)\right]\right)
& y \geq y_\text{cut}
\end{cases}\,,
\end{equation}
where $p_{\perp,\text{min}}$ is the minimum jet transverse momentum,
$p_{\perp,\text{max}}$ is the maximum transverse parton momentum,
tentatively set to the beam energy, and $y_\text{cut}$, $p_{\perp,\text{par}}$
and $\tilde{p}_{\perp,\text{par}}$ are generation parameters set to
heuristically determined values of
\begin{align}
y_\text{cut}&=3,\\
p_{\perp,\text{par}}&=p_{\perp,\min}+\frac{n_p}{5}, \\
\tilde{p}_{\perp,\text{par}}&=\frac{p_{\perp,\text{par}}}{1 +
5(y-y_\text{cut})}.
\end{align}
The problem with this generation is that the transverse momenta peak at
the minimum transverse momentum required for fixed-order jets. However,
if we use the generated events as input for \HEJ resummation, events
with such soft transverse momenta hardly contribute, see
section~\ref{sec:ptj_res}. To generate efficient input for resummation,
there is the user option \texttt{peak pt}, which specifies the
dominant transverse momentum for resummation jets. If this option is
set, most jets will be generated as above, but with
$p_{\perp,\text{min}}$ set to the peak transverse momentum $p_{\perp,
\text{peak}}$. In addition, there is a small chance of around $2\%$ to
generate softer jets. The heuristic ansatz for the transverse momentum
distribution in the ``soft'' region is
\begin{equation}
\label{FO_pt_soft}
\frac{\partial \sigma}{\partial p_\perp} \propto e^{n_p\frac{p_\perp- p_{\perp,
\text{peak}}}{\bar{p}_\perp}}\,,
\end{equation}
where $n_p$ is the number of partons and $\bar{p}_\perp \approx
4\,$GeV. To achieve this distribution, we use
\begin{equation}
\label{eq:FO_pt_soft_sampling}
p_\perp = p_{\perp, \text{peak}} + \bar{p}_\perp \frac{\log x_{p_\perp}}{n_p}
\end{equation}
and discard the phase space point if the parton is too soft, i.e. below the threshold for
fixed-order jets.
After ensuring that all partons form separate jets, we generate any
potential colourless emissions. We then determine the incoming momenta
and flavours in \lstinline!PhaseSpacePoint::reconstruct_incoming! and
adjust the outgoing flavours to ensure an FKL configuration. Finally, we
may reassign outgoing flavours to generate suppressed (for example
unordered) configurations.
\subsection{Unweighting}
\label{sec:unweight}
Straightforward event generation tends to produce many events with small
weights. Those events have a negligible contribution to the final
observables, but can take up considerable storage space and CPU time in
later processing stages. This problem can be addressed by unweighting.
For naive unweighting, one would determine the maximum weight
$w_\text{max}$ of all events, discard each event with weight $w$ with a
probability $p=w/w_\text{max}$, and set the weights of all remaining
events to $w_\text{max}$. The downside to this procedure is that it also
eliminates a sizeable fraction of events with moderate weight, so that
the statistical convergence deteriorates.
To ameliorate this problem, we perform unweighting only for events with
sufficiently small weights. This is done by the
\lstinline!Unweighter! class. In the constructor we estimate the
mean and width of the weight-weight distribution from a sample of
events. We use these estimates to determine the maximum weight below
which unweighting is performed. The actual unweighting is the done in
the \lstinline!Unweighter::unweight! function.
\input{currents}
\appendix
\section{Continuous Integration}
\label{sec:gitlabCI}
GitLab provides ways to directly test code via \textit{Continuous integrations}.
The CI is controlled by \texttt{.gitlab-ci.yml}. For all options for the YAML
file see \href{https://docs.gitlab.com/ee/ci/yaml/}{docs.gitlab.com/ee/ci/yaml/}.
GitLab also provides a small tool to check that YAML syntax is correct under
\lstinline!CI/CD > Pipelines > CI Lint! or
\href{https://gitlab.dur.scotgrid.ac.uk/hej/HEJ/-/ci/lint}{gitlab.dur.scotgrid.ac.uk/hej/HEJ/-/ci/lint}.
Currently the CI is configured to trigger a \textit{Pipeline} on each
\lstinline!git push!. The corresponding \textit{GitLab runners} are configured
under \lstinline!CI/CD Settings>Runners! in the GitLab UI. All runners use a
\href{https://www.docker.com/}{docker} image as virtual environments\footnote{To
use only Docker runners set the \lstinline!docker! tag in
\texttt{.gitlab-ci.yml}.}. The specific docker images maintained separately. If
you add a new dependences, please also provide a docker image for the CI. The
goal to be able to test \HEJ with all possible configurations.
Each pipeline contains multiple stages (see \lstinline!stages! in
\texttt{.gitlab-ci.yml}) which are executed in order from top to bottom.
Additionally each stage contains multiple jobs. For example the stage
\textit{build} contains the jobs \lstinline!build:basic!,
\lstinline!build:qcdloop!, \lstinline!build:rivet!, etc., which compile \HEJ for
different environments and dependences, by using different in the Docker images.
Jobs staring with an dot are ignored by the Runner, e.g. \lstinline!.HEJ_build!
is only used as a template but never executed directly. Only after all jobs of
the previous stage was executed without any error the next stage will start.
To pass information between one stage and the next we use \lstinline!artifacts!.
The runner will automatically load all artifacts form all
\lstinline!dependencies! for each job\footnote{If no dependencies are defined
\textit{all} artifacts from all previous jobs are downloaded. Thus please
specify an empty dependence if you do not want to load any artifacts.}. For
example the compiled \HEJ code from \lstinline!build:basic! gets loaded in
\lstinline!test:basic! and \lstinline!FOG:build:basic!, without recompiling \HEJ
again. Additionally artifacts can be downloaded from the GitLab web page, which
could be handy for debugging.
The actual commands are given in the \lstinline!before_script!,
\lstinline!script! and \lstinline!after_script!
\footnote{\lstinline!after_script! is always executed} sections, and are
standard Linux shell commands (dependent on the docker image). Any failed
command, i.e. returning not zero, stops the job and making the pipeline fail
entirely. Most tests are just running \lstinline!make test! or are based on it.
Thus, to emphasise it again, write tests for your code in \lstinline!cmake!. The
CI is only intended to make automated testing in different environments easier.
\bibliographystyle{JHEP}
\bibliography{biblio}
\end{document}
diff --git a/doc/developer_manual/figures/ColourConnects_FKL.pdf b/doc/developer_manual/figures/ColourConnects_FKL.pdf
new file mode 100755
index 0000000..f011d62
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diff --git a/doc/developer_manual/figures/ColourConnects_crossed.pdf b/doc/developer_manual/figures/ColourConnects_crossed.pdf
new file mode 100755
index 0000000..e161928
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diff --git a/doc/developer_manual/figures/colour_centralqqx.jpg b/doc/developer_manual/figures/colour_centralqqx.jpg
new file mode 100644
index 0000000..84ea16a
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diff --git a/doc/developer_manual/figures/colour_gleft.jpg b/doc/developer_manual/figures/colour_gleft.jpg
new file mode 100644
index 0000000..9a24558
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diff --git a/doc/developer_manual/figures/colour_gright.jpg b/doc/developer_manual/figures/colour_gright.jpg
new file mode 100644
index 0000000..32e5179
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diff --git a/doc/developer_manual/figures/colour_qx.jpg b/doc/developer_manual/figures/colour_qx.jpg
new file mode 100644
index 0000000..344bbc0
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diff --git a/doc/developer_manual/figures/colour_uno.jpg b/doc/developer_manual/figures/colour_uno.jpg
new file mode 100644
index 0000000..362686c
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diff --git a/doc/developer_manual/src/ColourConnect.tex b/doc/developer_manual/src/ColourConnect.tex
new file mode 100755
index 0000000..0330165
--- /dev/null
+++ b/doc/developer_manual/src/ColourConnect.tex
@@ -0,0 +1,52 @@
+\hspace{2cm}
+%% labels left
+\begin{minipage}[b]{0.5cm}
+ \begin{flushright}
+ $a$
+
+ \vspace{3.3cm}
+ $b$
+
+ \vspace{0.3cm}
+ \end{flushright}
+\end{minipage}
+\includegraphics[height=4.5cm]{figures/ColourConnects_FKL.pdf}
+\hspace{2.5cm}
+\includegraphics[height=4.5cm]{figures/ColourConnects_crossed.pdf}
+\hspace{-5.8cm}
+%% labels middle
+\begin{minipage}[b]{4cm}
+ $1$ \hspace{2cm} $a$
+
+ \vspace{0.9cm}
+ $2$
+
+ \vspace{0.8cm}
+ $3$
+
+ \vspace{0.7cm}
+ $4$ \hspace{2cm} $b$
+
+ \vspace{0.3cm}
+\end{minipage}
+\hspace{1.6cm}
+%% labels right
+\begin{minipage}[b]{0.5cm}
+ $1$
+
+ \vspace{0.8cm}
+ $2$
+
+ \vspace{0.8cm}
+ $3$
+
+ \vspace{0.8cm}
+ $4$
+
+ \vspace{0.3cm}
+\end{minipage}
+
+%%% Local Variables:
+%%% mode: latex
+%%% TeX-master: "../developer_manual"
+%%% End:
diff --git a/doc/doxygen/biblio.bib b/doc/doxygen/biblio.bib
index 5fce287..3e960be 100644
--- a/doc/doxygen/biblio.bib
+++ b/doc/doxygen/biblio.bib
@@ -1,56 +1,86 @@
@article{Andersen:2011hs,
author = "Andersen, Jeppe R. and Smillie, Jennifer M.",
title = "{Multiple Jets at the LHC with High Energy Jets}",
journal = "JHEP",
volume = "06",
year = "2011",
pages = "010",
doi = "10.1007/JHEP06(2011)010",
eprint = "1101.5394",
archivePrefix = "arXiv",
primaryClass = "hep-ph",
reportNumber = "CP3-ORIGINS-2011-02, EDINBURGH-2011-03",
SLACcitation = "%%CITATION = ARXIV:1101.5394;%%"
}
@article{James:1993np,
author = "James, F.",
title = "{RANLUX: A FORTRAN implementation of the high quality
pseudorandom number generator of Luscher}",
journal = "Comput. Phys. Commun.",
volume = "79",
year = "1994",
pages = "111-114",
doi = "10.1016/0010-4655(94)90233-X",
note = "[Erratum: Comput. Phys. Commun.97,357(1996)]",
reportNumber = "CERN-CN-93-13",
SLACcitation = "%%CITATION = CPHCB,79,111;%%"
}
@article{Luscher:1993dy,
author = "Luscher, Martin",
title = "{A Portable high quality random number generator for
lattice field theory simulations}",
journal = "Comput. Phys. Commun.",
volume = "79",
year = "1994",
pages = "100-110",
doi = "10.1016/0010-4655(94)90232-1",
eprint = "hep-lat/9309020",
archivePrefix = "arXiv",
primaryClass = "hep-lat",
reportNumber = "DESY-93-133",
SLACcitation = "%%CITATION = HEP-LAT/9309020;%%"
}
@article{Savvidy:2014ana,
author = "Savvidy, Konstantin G.",
title = "{The MIXMAX random number generator}",
journal = "Comput. Phys. Commun.",
volume = "196",
year = "2015",
pages = "161-165",
doi = "10.1016/j.cpc.2015.06.003",
eprint = "1403.5355",
archivePrefix = "arXiv",
primaryClass = "hep-lat",
reportNumber = "NITS-PHY-2014, NITS-PHY-2014003",
SLACcitation = "%%CITATION = ARXIV:1403.5355;%%"
}
+@inproceedings{Boos:2001cv,
+ author = "Boos, E. and others",
+ title = "{Generic user process interface for event generators}",
+ booktitle = "{Physics at TeV colliders. Proceedings, Euro Summer
+ School, Les Houches, France, May 21-June 1, 2001}",
+ url = "http://lss.fnal.gov/archive/preprint/fermilab-conf-01-496-t.shtml",
+ year = "2001",
+ eprint = "hep-ph/0109068",
+ archivePrefix = "arXiv",
+ primaryClass = "hep-ph",
+ reportNumber = "FERMILAB-CONF-01-496-T",
+ SLACcitation = "%%CITATION = HEP-PH/0109068;%%"
+}
+@article{Andersen:2011zd,
+ author = "Andersen, Jeppe R. and Lonnblad, Leif and Smillie,
+ Jennifer M.",
+ title = "{A Parton Shower for High Energy Jets}",
+ journal = "JHEP",
+ volume = "07",
+ year = "2011",
+ pages = "110",
+ doi = "10.1007/JHEP07(2011)110",
+ eprint = "1104.1316",
+ archivePrefix = "arXiv",
+ primaryClass = "hep-ph",
+ reportNumber = "CERN-PH-TH-2011-072, CP3-ORIGINS-2011-14,
+ EDINBURGH-2011-16, LU-TP-11-15, MCNET-11-12, LU-TP
+ --11-15",
+ SLACcitation = "%%CITATION = ARXIV:1104.1316;%%"
+}
diff --git a/doc/sphinx/conf.py b/doc/sphinx/conf.py
index a9d958d..12fdfff 100644
--- a/doc/sphinx/conf.py
+++ b/doc/sphinx/conf.py
@@ -1,175 +1,175 @@
# -*- coding: utf-8 -*-
#
# HEJ 2 documentation build configuration file, created by
# sphinx-quickstart on Fri Sep 15 16:13:57 2017.
#
# This file is execfile()d with the current directory set to its
# containing dir.
#
# Note that not all possible configuration values are present in this
# autogenerated file.
#
# All configuration values have a default; values that are commented out
# serve to show the default.
# If extensions (or modules to document with autodoc) are in another directory,
# add these directories to sys.path here. If the directory is relative to the
# documentation root, use os.path.abspath to make it absolute, like shown here.
#
# import os
# import sys
# sys.path.insert(0, os.path.abspath('.'))
# -- General configuration ------------------------------------------------
# If your documentation needs a minimal Sphinx version, state it here.
#
# needs_sphinx = '1.0'
# Add any Sphinx extension module names here, as strings. They can be
# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
# ones.
extensions = ['sphinx.ext.mathjax',
'sphinx.ext.githubpages']
# Add any paths that contain templates here, relative to this directory.
templates_path = ['_templates']
# The suffix(es) of source filenames.
# You can specify multiple suffix as a list of string:
#
# source_suffix = ['.rst', '.md']
source_suffix = '.rst'
# The master toctree document.
master_doc = 'index'
# General information about the project.
project = u'HEJ 2'
copyright = u'2017, Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie'
author = u'Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie'
# The version info for the project you're documenting, acts as replacement for
# |version| and |release|, also used in various other places throughout the
# built documents.
#
# The short X.Y version.
version = u'2.0'
# The full version, including alpha/beta/rc tags.
-release = u'2.0.4'
+release = u'2.0.5'
# The language for content autogenerated by Sphinx. Refer to documentation
# for a list of supported languages.
#
# This is also used if you do content translation via gettext catalogs.
# Usually you set "language" from the command line for these cases.
language = None
# List of patterns, relative to source directory, that match files and
# directories to ignore when looking for source files.
# This patterns also effect to html_static_path and html_extra_path
exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
highlight_language = 'C++'
# The name of the Pygments (syntax highlighting) style to use.
pygments_style = 'sphinx'
# If true, `todo` and `todoList` produce output, else they produce nothing.
todo_include_todos = False
# -- Options for HTML output ----------------------------------------------
# The theme to use for HTML and HTML Help pages. See the documentation for
# a list of builtin themes.
html_theme = 'alabaster'
# Theme options are theme-specific and customize the look and feel of a theme
# further. For a list of options available for each theme, see the
# documentation.
html_theme_options = {
'body_text': '#000000',
'narrow_sidebar_fg': '#000000',
'sidebar_header': '#000000',
'sidebar_link': '#000000',
'sidebar_text': '#000000'
}
# Add any paths that contain custom static files (such as style sheets) here,
# relative to this directory. They are copied after the builtin static files,
# so a file named "default.css" will overwrite the builtin "default.css".
# html_static_path = ['_static']
# Custom sidebar templates, must be a dictionary that maps document names
# to template names.
#
# This is required for the alabaster theme
# refs: http://alabaster.readthedocs.io/en/latest/installation.html#sidebars
html_sidebars = {
'**': [
'about.html',
'navigation.html',
'relations.html', # needs 'show_related': True theme option to display
'searchbox.html',
'donate.html',
]
}
# -- Options for HTMLHelp output ------------------------------------------
# Output file base name for HTML help builder.
htmlhelp_basename = 'HEJ2doc'
# -- Options for LaTeX output ---------------------------------------------
latex_elements = {
# The paper size ('letterpaper' or 'a4paper').
#
# 'papersize': 'letterpaper',
# The font size ('10pt', '11pt' or '12pt').
#
# 'pointsize': '10pt',
# Additional stuff for the LaTeX preamble.
#
# 'preamble': '',
# Latex figure (float) alignment
#
# 'figure_align': 'htbp',
}
# Grouping the document tree into LaTeX files. List of tuples
# (source start file, target name, title,
# author, documentclass [howto, manual, or own class]).
latex_documents = [
(master_doc, 'HEJ2.tex', u'HEJ 2 Documentation',
u'Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie', 'manual'),
]
# -- Options for manual page output ---------------------------------------
# One entry per manual page. List of tuples
# (source start file, name, description, authors, manual section).
man_pages = [
(master_doc, 'hej2', u'HEJ 2 Documentation',
[author], 1)
]
# -- Options for Texinfo output -------------------------------------------
# Grouping the document tree into Texinfo files. List of tuples
# (source start file, target name, title, author,
# dir menu entry, description, category)
texinfo_documents = [
(master_doc, 'HEJ2', u'HEJ 2 Documentation',
author, 'HEJ2', 'One line description of project.',
'Miscellaneous'),
]
diff --git a/include/HEJ/Constants.hh b/include/HEJ/Constants.hh
index f73bb41..0c357d9 100644
--- a/include/HEJ/Constants.hh
+++ b/include/HEJ/Constants.hh
@@ -1,33 +1,38 @@
/** \file
* \brief Header file defining all global constants used for HEJ
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#pragma once
namespace HEJ{
/// @name QCD parameters
//@{
constexpr double N_C = 3.; //!< number of Colours
constexpr double C_A = N_C; //!< \f$C_A\f$
constexpr double C_F = (N_C*N_C - 1.)/(2.*N_C); //!< \f$C_F\f$
constexpr double t_f = 0.5; //!< \f$t_f\f$
constexpr double n_f = 5.; //!< number light flavours
constexpr double beta0 = 11./3.*C_A - 4./3.*t_f*n_f; //!< \f$\beta_0\f$
//@}
/// @name QFT parameters
//@{
constexpr double vev = 246.2196508; //!< Higgs vacuum expectation value in GeV
constexpr double gw = 0.653233;
constexpr double MW = 80.419; // The W mass in GeV/c^2
constexpr double GammaW = 2.0476; // the W width in GeV/c^2
//@}
/// @name Generation Parameters
//@{
constexpr double CLAMBDA = 0.2; //!< Scale for virtual correction, \f$\lambda\f$ cf. eq. (20) in \cite Andersen:2011hs
constexpr double CMINPT = 0.2; //!< minimal \f$p_t\f$ of all partons
//@}
+/// @name Conventional Parameters
+//@{
+ //! Value of first colour for colour dressing, according to LHE convention \cite Boos:2001cv
+ constexpr int COLOUR_OFFSET = 501;
+//@}
}
diff --git a/include/HEJ/Event.hh b/include/HEJ/Event.hh
index 6b59620..71b5503 100644
--- a/include/HEJ/Event.hh
+++ b/include/HEJ/Event.hh
@@ -1,199 +1,275 @@
/** \file
* \brief Declares the Event class and helpers
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#pragma once
#include <array>
#include <memory>
#include <string>
#include <unordered_map>
#include <vector>
#include "HEJ/event_types.hh"
+#include "HEJ/Parameters.hh"
#include "HEJ/Particle.hh"
+#include "HEJ/RNG.hh"
#include "fastjet/ClusterSequence.hh"
namespace LHEF{
class HEPEUP;
class HEPRUP;
}
namespace fastjet{
class JetDefinition;
}
namespace HEJ{
+ struct UnclusteredEvent;
- struct ParameterDescription;
-
- //! Event parameters
- struct EventParameters{
- double mur; /**< Value of the Renormalisation Scale */
- double muf; /**< Value of the Factorisation Scale */
- double weight; /**< Event Weight */
- //! Optional description
- std::shared_ptr<ParameterDescription> description = nullptr;
- };
-
- //! Description of event parameters
- struct ParameterDescription {
- //! Name of central scale choice (e.g. "H_T/2")
- std::string scale_name;
- //! Actual renormalisation scale divided by central scale
- double mur_factor;
- //! Actual factorisation scale divided by central scale
- double muf_factor;
-
- ParameterDescription() = default;
- ParameterDescription(
- std::string scale_name, double mur_factor, double muf_factor
- ):
- scale_name{scale_name}, mur_factor{mur_factor}, muf_factor{muf_factor}
- {};
- };
-
- //! An event before jet clustering
- struct UnclusteredEvent{
- //! Default Constructor
- UnclusteredEvent() = default;
- //! Constructor from LesHouches event information
- UnclusteredEvent(LHEF::HEPEUP const & hepeup);
-
- std::array<Particle, 2> incoming; /**< Incoming Particles */
- std::vector<Particle> outgoing; /**< Outgoing Particles */
- //! Particle decays in the format {outgoing index, decay products}
- std::unordered_map<size_t, std::vector<Particle>> decays;
- //! Central parameter (e.g. scale) choice
- EventParameters central;
- std::vector<EventParameters> variations; /**< For parameter variation */
- };
-
- /** An event with clustered jets
+ /** @brief An event with clustered jets
*
* This is the main HEJ 2 event class.
* It contains kinematic information including jet clustering,
* parameter (e.g. scale) settings and the event weight.
*/
class Event{
public:
- //! Default Event Constructor
- Event() = default;
+ class EventData;
+ //! No default Constructor
+ Event() = delete;
//! Event Constructor adding jet clustering to an unclustered event
+ //! @deprecated UnclusteredEvent will be replaced by EventData in HEJ 2.3.0
+ [[deprecated("UnclusteredEvent will be replaced by EventData")]]
Event(
- UnclusteredEvent ev,
- fastjet::JetDefinition const & jet_def, double min_jet_pt
+ UnclusteredEvent const & ev,
+ fastjet::JetDefinition const & jet_def, double min_jet_pt
);
//! The jets formed by the outgoing partons
std::vector<fastjet::PseudoJet> jets() const;
- //! The corresponding event before jet clustering
- UnclusteredEvent const & unclustered() const {
- return ev_;
- }
-
- //! Central parameter choice
- EventParameters const & central() const{
- return ev_.central;
- }
-
- //! Central parameter choice
- EventParameters & central(){
- return ev_.central;
- }
-
//! Incoming particles
std::array<Particle, 2> const & incoming() const{
- return ev_.incoming;
+ return incoming_;
}
-
//! Outgoing particles
std::vector<Particle> const & outgoing() const{
- return ev_.outgoing;
+ return outgoing_;
}
-
//! Particle decays
/**
* The key in the returned map corresponds to the index in the
* vector returned by outgoing()
*/
std::unordered_map<size_t, std::vector<Particle>> const & decays() const{
- return ev_.decays;
+ return decays_;
}
- //! Parameter (scale) variations
- std::vector<EventParameters> const & variations() const{
- return ev_.variations;
+ //! All chosen parameter, i.e. scale choices (const version)
+ Parameters<EventParameters> const & parameters() const{
+ return parameters_;
+ }
+ //! All chosen parameter, i.e. scale choices
+ Parameters<EventParameters> & parameters(){
+ return parameters_;
+ }
+
+ //! Central parameter choice (const version)
+ EventParameters const & central() const{
+ return parameters_.central;
+ }
+ //! Central parameter choice
+ EventParameters & central(){
+ return parameters_.central;
}
+ //! Parameter (scale) variations (const version)
+ std::vector<EventParameters> const & variations() const{
+ return parameters_.variations;
+ }
//! Parameter (scale) variations
std::vector<EventParameters> & variations(){
- return ev_.variations;
+ return parameters_.variations;
}
- //! Parameter (scale) variation
+ //! Parameter (scale) variation (const version)
/**
* @param i Index of the requested variation
*/
EventParameters const & variations(size_t i) const{
- return ev_.variations[i];
+ return parameters_.variations[i];
}
-
//! Parameter (scale) variation
/**
* @param i Index of the requested variation
*/
EventParameters & variations(size_t i){
- return ev_.variations[i];
+ return parameters_.variations[i];
}
//! Indices of the jets the outgoing partons belong to
/**
* @param jets Jets to be tested
* @returns A vector containing, for each outgoing parton,
* the index in the vector of jets the considered parton
* belongs to. If the parton is not inside any of the
* passed jets, the corresponding index is set to -1.
*/
std::vector<int> particle_jet_indices(
std::vector<fastjet::PseudoJet> const & jets
) const{
return cs_.particle_jet_indices(jets);
}
//! Jet definition used for clustering
fastjet::JetDefinition const & jet_def() const{
return cs_.jet_def();
}
//! Minimum jet transverse momentum
double min_jet_pt() const{
return min_jet_pt_;
}
//! Event type
event_type::EventType type() const{
return type_;
}
+ //! Give colours to each particle
+ /**
+ * @returns true if new colours are generated, i.e. same as is_HEJ()
+ * @details Colour ordering is done according to leading colour in the MRK
+ * limit, see \cite Andersen:2011zd. This only affects \ref
+ * is_HEJ() "HEJ" configurations, all other \ref event_type
+ * "EventTypes" will be ignored.
+ * @note This overwrites all previously set colours.
+ */
+ bool generate_colours(HEJ::RNG &);
+
private:
- UnclusteredEvent ev_;
+ //! \internal
+ //! @brief Construct Event explicitly from input.
+ /** This is only intended to be called from EventData.
+ *
+ * \warning The input is taken _as is_, sorting and classification has to be
+ * done externally, i.e. by EventData
+ */
+ Event(
+ std::array<Particle, 2> && incoming,
+ std::vector<Particle> && outgoing,
+ std::unordered_map<size_t, std::vector<Particle>> && decays,
+ Parameters<EventParameters> && parameters,
+ fastjet::JetDefinition const & jet_def,
+ double const min_jet_pt
+ ): incoming_{std::move(incoming)},
+ outgoing_{std::move(outgoing)},
+ decays_{std::move(decays)},
+ parameters_{std::move(parameters)},
+ cs_{ to_PseudoJet( filter_partons(outgoing_) ), jet_def },
+ min_jet_pt_{min_jet_pt}
+ {};
+
+ std::array<Particle, 2> incoming_;
+ std::vector<Particle> outgoing_;
+ std::unordered_map<size_t, std::vector<Particle>> decays_;
+ Parameters<EventParameters> parameters_;
fastjet::ClusterSequence cs_;
double min_jet_pt_;
event_type::EventType type_;
- };
+ }; // end class Event
+
+ //! Class to store general Event setup, i.e. Phase space and weights
+ class Event::EventData{
+ public:
+ //! Default Constructor
+ EventData() = default;
+ //! Constructor from LesHouches event information
+ EventData(LHEF::HEPEUP const & hepeup);
+ //! Constructor with all values given
+ EventData(
+ std::array<Particle, 2> const & incoming_,
+ std::vector<Particle> const & outgoing_,
+ std::unordered_map<size_t, std::vector<Particle>> const & decays_,
+ Parameters<EventParameters> const & parameters_
+ ):
+ incoming(incoming_), outgoing(outgoing_),
+ decays(decays_), parameters(parameters_)
+ {};
+ //! Move Constructor with all values given
+ EventData(
+ std::array<Particle, 2> && incoming_,
+ std::vector<Particle> && outgoing_,
+ std::unordered_map<size_t, std::vector<Particle>> && decays_,
+ Parameters<EventParameters> && parameters_
+ ):
+ incoming(std::move(incoming_)), outgoing(std::move(outgoing_)),
+ decays(std::move(decays_)), parameters(std::move(parameters_))
+ {};
+
+ //! Generate an Event from the stored EventData.
+ /**
+ * @details Do jet clustering and classification.
+ * Use this to generate an Event.
+ *
+ * @note Calling this function destroys EventData
+ *
+ * @param jet_def Jet definition
+ * @param min_jet_pt minimal \f$p_T\f$ for each jet
+ *
+ * @returns Full clustered and classified event.
+ */
+ Event cluster(
+ fastjet::JetDefinition const & jet_def, double const min_jet_pt);
+
+ //! Alias for cluster()
+ Event operator()(
+ fastjet::JetDefinition const & jet_def, double const min_jet_pt){
+ return cluster(jet_def, min_jet_pt);
+ };
+
+ //! Sort particles in rapidity
+ void sort();
+
+ std::array<Particle, 2> incoming;
+ std::vector<Particle> outgoing;
+ std::unordered_map<size_t, std::vector<Particle>> decays;
+ Parameters<EventParameters> parameters;
+ }; // end class EventData
//! Square of the partonic centre-of-mass energy \f$\hat{s}\f$
double shat(Event const & ev);
//! Convert an event to a LHEF::HEPEUP
LHEF::HEPEUP to_HEPEUP(Event const & event, LHEF::HEPRUP *);
+ // put deprecated warning at the end, so don't get the warning inside Event.hh,
+ // additionally doxygen can not identify [[deprecated]] correctly
+ struct [[deprecated("UnclusteredEvent will be replaced by EventData")]]
+ UnclusteredEvent;
+ //! An event before jet clustering
+ //! @deprecated UnclusteredEvent will be replaced by EventData in HEJ 2.3.0
+ struct UnclusteredEvent{
+ //! Default Constructor
+ UnclusteredEvent() = default;
+ //! Constructor from LesHouches event information
+ UnclusteredEvent(LHEF::HEPEUP const & hepeup);
+
+ std::array<Particle, 2> incoming; /**< Incoming Particles */
+ std::vector<Particle> outgoing; /**< Outgoing Particles */
+ //! Particle decays in the format {outgoing index, decay products}
+ std::unordered_map<size_t, std::vector<Particle>> decays;
+ //! Central parameter (e.g. scale) choice
+ EventParameters central;
+ std::vector<EventParameters> variations; /**< For parameter variation */
+ };
+
}
diff --git a/include/HEJ/EventReweighter.hh b/include/HEJ/EventReweighter.hh
index b6b1c2d..e139ce1 100644
--- a/include/HEJ/EventReweighter.hh
+++ b/include/HEJ/EventReweighter.hh
@@ -1,190 +1,190 @@
/** \file
* \brief Declares the EventReweighter class
*
* EventReweighter is the main class used within HEJ 2. It reweights the
* resummation events.
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#pragma once
#include <array>
#include <functional>
#include <utility>
#include <vector>
#include "HEJ/config.hh"
#include "HEJ/event_types.hh"
#include "HEJ/MatrixElement.hh"
#include "HEJ/PDF.hh"
#include "HEJ/PDG_codes.hh"
#include "HEJ/RNG.hh"
#include "HEJ/ScaleFunction.hh"
+#include "HEJ/Parameters.hh"
namespace LHEF {
class HEPRUP;
}
namespace HEJ{
class Event;
- class Weights;
//! Beam parameters
/**
* Currently, only symmetric beams are supported,
* so there is a single beam energy.
*/
struct Beam{
double E; /**< Beam energy */
std::array<ParticleID, 2> type; /**< Beam particles */
};
//! Main class for reweighting events in HEJ.
class EventReweighter{
using EventType = event_type::EventType;
public:
EventReweighter(
Beam beam, /**< Beam Energy */
int pdf_id, /**< PDF ID */
ScaleGenerator scale_gen, /**< Scale settings */
EventReweighterConfig conf, /**< Configuration parameters */
HEJ::RNG & ran /**< Random number generator */
);
EventReweighter(
LHEF::HEPRUP const & heprup, /**< LHEF event header */
ScaleGenerator scale_gen, /**< Scale settings */
EventReweighterConfig conf, /**< Configuration parameters */
HEJ::RNG & ran /**< Random number generator */
);
//! Get the used pdf
PDF const & pdf() const;
//! Generate resummation events for a given fixed-order event
/**
* @param ev Fixed-order event corresponding
* to the resummation events
* @param num_events Number of trial resummation configurations.
* @returns A vector of resummation events.
*
* The result vector depends on the type of the input event and the
* treatment of different types as specified in the constructor:
*
* \ref reweight The result vector contains between
* 0 and num_events resummation events.
*
* \ref keep If the input event passes the resummation jet cuts
* the result vector contains one event. Otherwise it is empty.
*
* \ref discard The result vector is empty
*/
std::vector<Event> reweight(
Event const & ev,
int num_events
);
private:
template<typename... T>
PDF const & pdf(T&& ...);
/** \internal
* \brief main generation/reweighting function:
* generate phase space points and divide out Born factors
*/
std::vector<Event> gen_res_events(
Event const & ev, int num_events
);
std::vector<Event> rescale(
Event const & Born_ev, std::vector<Event> events
) const;
/** \internal
* \brief Do the Jets pass the resummation Cuts?
*
* @param ev Event in Question
* @returns 0 or 1 depending on if ev passes Jet Cuts
*/
bool jets_pass_resummation_cuts(Event const & ev) const;
/** \internal
* \brief pdf_factors Function
*
* @param ev Event in Question
* @returns EventFactor due to PDFs
*
* Calculates the Central value and the variation due
* to the PDF choice made.
*/
Weights pdf_factors(Event const & ev) const;
/** \internal
* \brief matrix_elements Function
*
* @param ev Event in question
* @returns EventFactor due to MatrixElements
*
* Calculates the Central value and the variation due
* to the Matrix Element.
*/
Weights matrix_elements(Event const & ev) const;
/** \internal
* \brief Scale-dependent part of fixed-order matrix element
*
* @param ev Event in question
* @returns EventFactor scale variation due to FO-ME.
*
* This is only called to compute the scale variation for events where
* we don't do resummation (e.g. non-FKL).
* Since at tree level the scale dependence is just due to alpha_s,
* it is enough to return the alpha_s(mur) factors in the matrix element.
* The rest drops out in the ratio of (output event ME)/(input event ME),
* so we never have to compute it.
*/
Weights fixed_order_scale_ME(Event const & ev) const;
/** \internal
* \brief Computes the tree level matrix element
*
* @param ev Event in Question
* @returns HEJ approximation to Tree level Matrix Element
*
* This computes the HEJ approximation to the tree level FO
* Matrix element which is used within the LO weighting process.
*/
double tree_matrix_element(Event const & ev) const;
//! \internal General parameters
EventReweighterConfig param_;
//! \internal Beam energy
double E_beam_;
//! \internal PDF
PDF pdf_;
//! \internal Object to calculate the square of the matrix element
MatrixElement MEt2_;
//! \internal Object to calculate event renormalisation and factorisation scales
ScaleGenerator scale_gen_;
/** \internal random number generator
*
* \note We use a reference_wrapper so that EventReweighter objects can
* still be copied (which would be impossible with a reference).
*/
std::reference_wrapper<HEJ::RNG> ran_;
};
template<typename... T>
PDF const & EventReweighter::pdf(T&&... t){
return pdf_ = PDF{std::forward<T>(t)...};
}
}
diff --git a/include/HEJ/MatrixElement.hh b/include/HEJ/MatrixElement.hh
index 8df28b9..cfcd15f 100644
--- a/include/HEJ/MatrixElement.hh
+++ b/include/HEJ/MatrixElement.hh
@@ -1,191 +1,191 @@
/** \file
* \brief Contains the MatrixElement Class
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#pragma once
#include <functional>
#include <vector>
#include "fastjet/PseudoJet.hh"
#include "HEJ/PDG_codes.hh"
-#include "HEJ/Weights.hh"
+#include "HEJ/Parameters.hh"
#include "HEJ/config.hh"
namespace CLHEP {
class HepLorentzVector;
}
namespace HEJ{
class Event;
class Particle;
//! Class to calculate the squares of matrix elements
class MatrixElement{
public:
/** \brief MatrixElement Constructor
* @param alpha_s Function taking the renormalisation scale
* and returning the strong coupling constant
* @param conf General matrix element settings
*/
MatrixElement(
std::function<double (double)> alpha_s,
MatrixElementConfig conf
);
/**
* \brief squares of regulated HEJ matrix elements
* @param event The event for which to calculate matrix elements
* @returns The squares of HEJ matrix elements including virtual corrections
*
* This function returns one value for the central parameter choice
* and one additional value for each entry in \ref Event.variations().
* See eq. (22) in \cite Andersen:2011hs for the definition of the squared
* matrix element.
*
* \internal Relation to standard HEJ Met2: MatrixElement = Met2*shat^2/(pdfta*pdftb)
*/
Weights operator()(Event const & event) const;
//! Squares of HEJ tree-level matrix elements
/**
* @param event The event for which to calculate matrix elements
* @returns The squares of HEJ matrix elements without virtual corrections
*
* cf. eq. (22) in \cite Andersen:2011hs
*/
Weights tree(Event const & event) const;
/**
* \brief Virtual corrections to matrix element squares
* @param event The event for which to calculate matrix elements
* @returns The virtual corrections to the squares of the matrix elements
*
* The all order virtual corrections to LL in the MRK limit is
* given by replacing 1/t in the scattering amplitude according to the
* lipatov ansatz.
*
* cf. second-to-last line of eq. (22) in \cite Andersen:2011hs
* note that indices are off by one, i.e. out[0].p corresponds to p_1
*/
Weights virtual_corrections(Event const & event) const;
/**
* \brief Scale-dependent part of tree-level matrix element squares
* @param event The event for which to calculate matrix elements
* @returns The scale-dependent part of the squares of the
* tree-level matrix elements
*
* The tree-level matrix elements factorises into a renormalisation-scale
* dependent part, given by the strong coupling to some power, and a
* scale-independent remainder. This function only returns the former parts
* for the central scale choice and all \ref Event.variations().
*
* @see tree, tree_kin
*/
Weights tree_param(
Event const & event
) const;
/**
* \brief Kinematic part of tree-level matrix element squares
* @param event The event for which to calculate matrix elements
* @returns The kinematic part of the squares of the
* tree-level matrix elements
*
* The tree-level matrix elements factorises into a renormalisation-scale
* dependent part, given by the strong coupling to some power, and a
* scale-independent remainder. This function only returns the latter part.
* Since it does not depend on the parameter variations, only a single value
* is returned.
*
* @see tree, tree_param
*/
double tree_kin(Event const & event) const;
private:
double tree_param(
Event const & event,
double mur
) const;
double virtual_corrections_W(
Event const & event,
double mur,
Particle const & WBoson
) const;
double virtual_corrections(
Event const & event,
double mur
) const;
//! \internal cf. last line of eq. (22) in \cite Andersen:2011hs
double omega0(
double alpha_s, double mur,
fastjet::PseudoJet const & q_j
) const;
double tree_kin_jets(
Event const & ev
) const;
double tree_kin_W(
Event const & ev
) const;
double tree_kin_Higgs(
Event const & ev
) const;
double tree_kin_Higgs_first(
Event const & ev
) const;
double tree_kin_Higgs_last(
Event const & ev
) const;
/**
* \internal
* \brief Higgs inbetween extremal partons.
*
* Note that in the case of unordered emission, the Higgs is *always*
* treated as if in between the extremal (FKL) partons, even if its
* rapidity is outside the extremal parton rapidities
*/
double tree_kin_Higgs_between(
Event const & ev
) const;
double tree_param_partons(
double alpha_s, double mur,
std::vector<Particle> const & partons
) const;
std::vector<int> in_extremal_jet_indices(
std::vector<fastjet::PseudoJet> const & partons
) const;
std::vector<Particle> tag_extremal_jet_partons(
Event const & ev
) const;
double MH2_forwardH(
CLHEP::HepLorentzVector p1out, CLHEP::HepLorentzVector p1in,
pid::ParticleID type2,
CLHEP::HepLorentzVector p2out, CLHEP::HepLorentzVector p2in,
CLHEP::HepLorentzVector pH,
double t1, double t2
) const;
std::function<double (double)> alpha_s_;
MatrixElementConfig param_;
};
}
diff --git a/include/HEJ/PDG_codes.hh b/include/HEJ/PDG_codes.hh
index 17c44a9..cf3ca3a 100644
--- a/include/HEJ/PDG_codes.hh
+++ b/include/HEJ/PDG_codes.hh
@@ -1,143 +1,143 @@
/** \file PDG_codes.hh
* \brief Contains the Particle IDs of all relevant SM particles.
*
* Large enumeration included which has multiple entries for potential
* alternative names of different particles. There are also functions
* which can be used to determine if a particle is a parton or if
* it is a non-gluon boson.
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#pragma once
#include <string>
namespace HEJ {
//! particle ids according to PDG
namespace pid {
//! The possible particle identities. We use PDG IDs as standard.
enum ParticleID{
d = 1, /*!< Down Quark */
down = d, /*!< Down Quark */
u = 2, /*!< Up Quark */
up = u, /*!< Up Quark */
s = 3, /*!< Strange Quark */
strange = s, /*!< Strange Quark */
c = 4, /*!< Charm Quark */
charm = c, /*!< Charm Quark */
b = 5, /*!< Bottom Quark */
bottom = b, /*!< Bottom Quark */
t = 6, /*!< Top Quark */
top = t, /*!< Top Quark */
e = 11, /*!< Electron */
electron = e, /*!< Electron */
nu_e = 12, /*!< Electron Neutrino */
electron_neutrino = nu_e, /*!< Electron neutrino */
mu = 13, /*!< Muon */
muon = mu, /*!< Muon */
nu_mu = 14, /*!< Muon Neutrino */
muon_neutrino = nu_mu, /*!< Muon Neutrino */
tau = 15, /*!< Tau */
nu_tau = 16, /*!< Tau Neutrino */
tau_neutrino = nu_tau, /*!< Tau Neutrino */
d_bar = -d, /*!< Anti-Down Quark */
u_bar = -u, /*!< Anti-Up quark */
s_bar = -s, /*!< Anti-Strange Quark */
c_bar = -c, /*!< Anti-Charm Quark */
b_bar = -b, /*!< Anti-Bottom Quark */
t_bar = -t, /*!< Anti-Top Quark */
e_bar = -e, /*!< Positron */
positron = e_bar, /*!< Positron */
nu_e_bar = -nu_e, /*!< Anti-Electron Neutrino */
mu_bar = -mu, /*!< Anti-Muon */
nu_mu_bar = -nu_mu, /*!< Anti-Muon Neutrino */
tau_bar = -tau, /*!< Anti-Tau */
nu_tau_bar = -nu_tau, /*!< Anti-Tau Neutrino */
gluon = 21, /*!< Gluon */
g = gluon, /*!< Gluon */
photon = 22, /*!< Photon */
gamma = photon, /*!< Photon */
Z = 23, /*!< Z Boson */
Wp = 24, /*!< W- Boson */
Wm = -Wp, /*!< W+ Boson */
h = 25, /*!< Higgs Boson */
Higgs = h, /*!< Higgs Boson */
higgs = h, /*!< Higgs Boson */
p = 2212, /*!< Proton */
proton = p, /*!< Proton */
p_bar = -p, /*!< Anti-Proton */
};
}
using ParticleID = pid::ParticleID;
//! Convert a particle name to the corresponding PDG particle ID
ParticleID to_ParticleID(std::string const & name);
/**
* \brief Function to determine if particle is a parton
* @param p PDG ID of particle
* @returns true if the particle is a parton, false otherwise
*/
inline
constexpr bool is_parton(ParticleID p){
return p == pid::gluon || std::abs(p) <= pid::top;
}
/**
- * \brief function to determine if the particle is a photon, W, Z, or Higgs boson
- * @param id PDG ID of particle
- * @returns true if the partice is a A,W,Z, or H, false otherwise
- */
- inline
- constexpr bool is_AWZH_boson(ParticleID id){
- return id == pid::Wm || (id >= pid::photon && id <= pid::Higgs);
- }
-
- /**
* \brief Function to determine if particle is a quark
* @param id PDG ID of particle
* @returns true if the particle is a qaurk, false otherwise
*/
inline
constexpr bool is_quark(ParticleID id){
return (id >= pid::down && id <= pid::top);
}
/**
* \brief Function to determine if particle is a antiquark
* @param id PDG ID of particle
* @returns true if the particle is an antiquark, false otherwise
*/
inline
constexpr bool is_antiquark(ParticleID id){
return (id <= pid::d_bar && id >= pid::t_bar);
}
/**
- * \brief Function to determine if particle is a any-quark
+ * \brief Function to determine if particle is a (anti-)quark
* @param id PDG ID of particle
* @returns true if the particle is a quark or antiquark, false otherwise
*/
inline
constexpr bool is_anyquark(ParticleID id){
return (id && id >= pid::t_bar && id <= pid::t);
}
/**
+ * \brief function to determine if the particle is a photon, W, Z, or Higgs boson
+ * @param id PDG ID of particle
+ * @returns true if the partice is a A,W,Z, or H, false otherwise
+ */
+ inline
+ constexpr bool is_AWZH_boson(ParticleID id){
+ return id == pid::Wm || (id >= pid::photon && id <= pid::Higgs);
+ }
+
+ /**
* \brief function to determine if the particle is a photon, W or Z
* @param id PDG ID of particle
* @returns true if the partice is a A,W,Z, or H, false otherwise
*/
inline
constexpr bool is_AWZ_boson(ParticleID id){
return id == pid::Wm || (id >= pid::photon && id <= pid::Wp);
}
}
diff --git a/include/HEJ/Parameters.hh b/include/HEJ/Parameters.hh
new file mode 100644
index 0000000..b9ed559
--- /dev/null
+++ b/include/HEJ/Parameters.hh
@@ -0,0 +1,155 @@
+/** \file
+ * \brief Containers for Parameter variations, e.g. different Weights
+ *
+ * \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
+ * \date 2019
+ * \copyright GPLv2 or later
+ */
+#pragma once
+
+#include <memory>
+#include <vector>
+
+#include "HEJ/exceptions.hh"
+
+namespace HEJ{
+ //! Collection of parameters, e.g. Weights, assigned to a single event
+ /**
+ * A number of member functions of the MatrixElement class return Parameters
+ * objects containing the squares of the matrix elements for the various
+ * scale choices.
+ */
+ template<class T>
+ struct Parameters {
+ T central;
+ std::vector<T> variations;
+
+ template<class T_ext>
+ Parameters<T>& operator*=(Parameters<T_ext> const & other);
+ Parameters<T>& operator*=(double factor);
+ template<class T_ext>
+ Parameters<T>& operator/=(Parameters<T_ext> const & other);
+ Parameters<T>& operator/=(double factor);
+ };
+
+ template<class T1, class T2> inline
+ Parameters<T1> operator*(Parameters<T1> a, Parameters<T2> const & b) {
+ a*=b;
+ return a;
+ }
+ template<class T> inline
+ Parameters<T> operator*(Parameters<T> a, double b) {
+ a*=b;
+ return a;
+ }
+ template<class T> inline
+ Parameters<T> operator*(double b, Parameters<T> a) {
+ a*=b;
+ return a;
+ }
+ template<class T1, class T2> inline
+ Parameters<T1> operator/(Parameters<T1> a, Parameters<T2> const & b) {
+ a/=b;
+ return a;
+ }
+ template<class T> inline
+ Parameters<T> operator/(Parameters<T> a, double b) {
+ a/=b;
+ return a;
+ }
+
+ //! Alias for weight container, e.g. used by the MatrixElement
+ using Weights = Parameters<double>;
+
+ //! Description of event parameters, see also EventParameters
+ struct ParameterDescription {
+ //! Name of central scale choice (e.g. "H_T/2")
+ std::string scale_name;
+ //! Actual renormalisation scale divided by central scale
+ double mur_factor;
+ //! Actual factorisation scale divided by central scale
+ double muf_factor;
+
+ ParameterDescription() = default;
+ ParameterDescription(
+ std::string scale_name, double mur_factor, double muf_factor
+ ):
+ scale_name{scale_name}, mur_factor{mur_factor}, muf_factor{muf_factor}
+ {};
+ };
+
+ //! Event parameters
+ struct EventParameters{
+ double mur; /**< Value of the Renormalisation Scale */
+ double muf; /**< Value of the Factorisation Scale */
+ double weight; /**< Event Weight */
+ //! Optional description
+ std::shared_ptr<ParameterDescription> description = nullptr;
+
+ //! multiply weight by factor
+ EventParameters& operator*=(double factor){
+ weight*=factor;
+ return *this;
+ };
+ //! divide weight by factor
+ EventParameters& operator/=(double factor){
+ weight/=factor;
+ return *this;
+ };
+ };
+ inline EventParameters operator*(EventParameters a, double b){
+ a*=b;
+ return a;
+ }
+ inline EventParameters operator*(double b, EventParameters a){
+ a*=b;
+ return a;
+ }
+ inline EventParameters operator/(EventParameters a, double b){
+ a/=b;
+ return a;
+ }
+
+ //! @{
+ //! @internal Implementation of template functions
+ template<class T>
+ template<class T_ext>
+ Parameters<T>& Parameters<T>::operator*=(Parameters<T_ext> const & other) {
+ if(other.variations.size() != variations.size()) {
+ throw std::invalid_argument{"Wrong number of Parameters"};
+ }
+ central *= other.central;
+ for(std::size_t i = 0; i < variations.size(); ++i) {
+ variations[i] *= other.variations[i];
+ }
+ return *this;
+ };
+
+ template<class T>
+ Parameters<T>& Parameters<T>::operator*=(double factor) {
+ central *= factor;
+ for(auto & wt: variations) wt *= factor;
+ return *this;
+ };
+
+ template<class T>
+ template<class T_ext>
+ Parameters<T>& Parameters<T>::operator/=(Parameters<T_ext> const & other) {
+ if(other.variations.size() != variations.size()) {
+ throw std::invalid_argument{"Wrong number of Parameters"};
+ }
+ central /= other.central;
+ for(std::size_t i = 0; i < variations.size(); ++i) {
+ variations[i] /= other.variations[i];
+ }
+ return *this;
+ };
+
+ template<class T>
+ Parameters<T>& Parameters<T>::operator/=(double factor) {
+ central /= factor;
+ for(auto & wt: variations) wt /= factor;
+ return *this;
+ };
+ //! @}
+}
diff --git a/include/HEJ/Particle.hh b/include/HEJ/Particle.hh
index cde958e..c6f321c 100644
--- a/include/HEJ/Particle.hh
+++ b/include/HEJ/Particle.hh
@@ -1,141 +1,148 @@
/**
* \file Particle.hh
* \brief Contains the particle struct
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#pragma once
+#include <utility>
+
#include "fastjet/PseudoJet.hh"
+#include "HEJ/optional.hh"
#include "HEJ/PDG_codes.hh"
namespace HEJ {
+ using Colour = std::pair<int,int>;
+
//! Class representing a particle
struct Particle {
//! particle type
ParticleID type;
//! particle momentum
fastjet::PseudoJet p;
+ //! (optional) colour & anti-colour
+ optional<Colour> colour;
//! get rapidity
double rapidity() const{
return p.rapidity();
}
//! get transverse momentum
double perp() const{
return p.perp();
}
//! get momentum in x direction
double px() const{
return p.px();
}
//! get momentum in y direction
double py() const{
return p.py();
}
//! get momentum in z direction
double pz() const{
return p.pz();
}
//! get energy
double E() const{
return p.E();
}
//! get mass
double m() const{
return p.m();
}
};
//! Functor to compare rapidities
/**
* This can be used whenever a rapidity comparison function is needed,
* for example in many standard library functions.
*
* @see pz_less
*/
struct rapidity_less{
template<class FourVector>
bool operator()(FourVector const & p1, FourVector const & p2){
return p1.rapidity() < p2.rapidity();
}
};
//! Functor to compare momenta in z direction
/**
* This can be used whenever a pz comparison function is needed,
* for example in many standard library functions.
*
* @see rapidity_less
*/
struct pz_less{
template<class FourVector>
bool operator()(FourVector const & p1, FourVector const & p2){
return p1.pz() < p2.pz();
}
};
//! Convert a vector of Particles to a vector of particle momenta
inline
std::vector<fastjet::PseudoJet> to_PseudoJet(
std::vector<Particle> const & v
){
std::vector<fastjet::PseudoJet> result;
for(auto && sp: v) result.emplace_back(sp.p);
return result;
}
//! Check if a particle is a parton, i.e. quark, antiquark, or gluon
inline
bool is_parton(Particle const & p){
return is_parton(p.type);
}
//! Check if a particle is a quark
inline
bool is_quark(Particle const & p){
return is_quark(p.type);
}
//! Check if a particle is an anti-quark
inline
bool is_antiquark(Particle const & p){
return is_antiquark(p.type);
}
- //! Check if a particle is a quark or any-quark
+ //! Check if a particle is a quark or anit-quark
inline
bool is_anyquark(Particle const & p){
return is_anyquark(p.type);
}
//! Check if a particle is a photon, W or Z boson
inline bool is_AWZ_boson(Particle const & particle){
return is_AWZ_boson(particle.type);
}
//! Check if a particle is a photon, W, Z, or Higgs boson
inline bool is_AWZH_boson(Particle const & particle){
return is_AWZH_boson(particle.type);
}
//! Extract all partons from a vector of particles
inline
std::vector<Particle> filter_partons(
std::vector<Particle> const & v
){
std::vector<Particle> result;
result.reserve(v.size());
std::copy_if(
begin(v), end(v), std::back_inserter(result),
[](Particle const & p){ return is_parton(p); }
);
return result;
}
}
diff --git a/include/HEJ/PhaseSpacePoint.hh b/include/HEJ/PhaseSpacePoint.hh
index 6bfce05..6189932 100644
--- a/include/HEJ/PhaseSpacePoint.hh
+++ b/include/HEJ/PhaseSpacePoint.hh
@@ -1,155 +1,155 @@
/** \file
* \brief Contains the PhaseSpacePoint Class
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#pragma once
#include <array>
#include <functional>
#include <unordered_map>
#include <vector>
#include "HEJ/config.hh"
#include "HEJ/Particle.hh"
#include "HEJ/RNG.hh"
namespace HEJ{
class Event;
//! A point in resummation phase space
class PhaseSpacePoint{
public:
//! Default PhaseSpacePoint Constructor
PhaseSpacePoint() = default;
//! PhaseSpacePoint Constructor
/**
* @param ev Clustered Jet Event
* @param conf Configuration parameters
* @param ran Random number generator
*/
PhaseSpacePoint(
Event const & ev,
PhaseSpacePointConfig conf,
- HEJ::RNG & ran
+ RNG & ran
);
//! Get phase space point weight
double weight() const{
return weight_;
}
//! Access incoming particles
std::array<Particle, 2> const & incoming() const{
return incoming_;
}
//! Access outgoing particles
std::vector<Particle> const & outgoing() const{
return outgoing_;
}
//! Particle decays
/**
* The key in the returned map corresponds to the index in the
* vector returned by outgoing()
*/
std::unordered_map<size_t, std::vector<Particle>> const & decays() const{
return decays_;
}
static constexpr int ng_max = 1000; //< maximum number of extra gluons
private:
std::vector<fastjet::PseudoJet> cluster_jets(
std::vector<fastjet::PseudoJet> const & partons
) const;
bool pass_resummation_cuts(
std::vector<fastjet::PseudoJet> const & jets
) const;
bool pass_extremal_cuts(
fastjet::PseudoJet const & ext_parton,
fastjet::PseudoJet const & jet
) const;
int sample_ng(std::vector<fastjet::PseudoJet> const & Born_jets);
int sample_ng_jets(int ng, std::vector<fastjet::PseudoJet> const & Born_jets);
double probability_in_jet(
std::vector<fastjet::PseudoJet> const & Born_jets
) const;
std::vector<fastjet::PseudoJet> gen_non_jet(
int ng_non_jet,
double ptmin, double ptmax
);
void rescale_rapidities(
std::vector<fastjet::PseudoJet> & partons,
double ymin, double ymax
);
std::vector<fastjet::PseudoJet> reshuffle(
std::vector<fastjet::PseudoJet> const & Born_jets,
fastjet::PseudoJet const & q
);
bool jets_ok(
std::vector<fastjet::PseudoJet> const & Born_jets,
std::vector<fastjet::PseudoJet> const & partons
) const;
void reconstruct_incoming(std::array<Particle, 2> const & Born_incoming);
double phase_space_normalisation(
int num_Born_jets,
int num_res_partons
) const;
std::vector<fastjet::PseudoJet> split(
std::vector<fastjet::PseudoJet> const & jets, int ng_jets
);
std::vector<int> distribute_jet_partons(
int ng_jets, std::vector<fastjet::PseudoJet> const & jets
);
std::vector<fastjet::PseudoJet> split(
std::vector<fastjet::PseudoJet> const & jets,
std::vector<int> const & np_in_jet
);
bool split_preserved_jets(
std::vector<fastjet::PseudoJet> const & jets,
std::vector<fastjet::PseudoJet> const & jet_partons
) const;
template<class Particle>
Particle const & most_backward_FKL(
std::vector<Particle> const & partons
) const;
template<class Particle>
Particle const & most_forward_FKL(
std::vector<Particle> const & partons
) const;
template<class Particle>
Particle & most_backward_FKL(std::vector<Particle> & partons) const;
template<class Particle>
Particle & most_forward_FKL(std::vector<Particle> & partons) const;
bool extremal_ok(
std::vector<fastjet::PseudoJet> const & partons
) const;
void label_qqx(Event const & event);
void copy_AWZH_boson_from(Event const & event);
bool momentum_conserved() const;
bool unob_, unof_, qqxb_, qqxf_, qqxmid_;
double weight_;
PhaseSpacePointConfig param_;
std::array<Particle, 2> incoming_;
std::vector<Particle> outgoing_;
//! \internal Particle decays in the format {outgoing index, decay products}
std::unordered_map<size_t, std::vector<Particle>> decays_;
std::reference_wrapper<HEJ::RNG> ran_;
};
}
diff --git a/include/HEJ/Weights.hh b/include/HEJ/Weights.hh
index fd34e92..1c1016f 100644
--- a/include/HEJ/Weights.hh
+++ b/include/HEJ/Weights.hh
@@ -1,49 +1,13 @@
/** \file
- * \brief Container for event weights
+ * \brief Legacy Header for Weights
+ * \note This Header was moved to "HEJ/Parameters.hh"
+ * \TODO remove in HEJ 2.3.0
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
+#warning "HEJ/Weights.hh is deprecated use HEJ/Parameters.hh instead"
#pragma once
-#include <vector>
-
-namespace HEJ{
- //! Collection of weights assigned to a single event
- /**
- * A number of member functions of the MatrixElement class return Weights
- * objects containing the squares of the matrix elements for the various
- * scale choices.
- */
- struct Weights {
- double central;
- std::vector<double> variations;
-
- Weights& operator*=(Weights const & other);
- Weights& operator*=(double factor);
- Weights& operator/=(Weights const & other);
- Weights& operator/=(double factor);
- };
-
- inline
- Weights operator*(Weights a, Weights const & b) {
- return a*=b;
- }
- inline
- Weights operator*(Weights a, double b) {
- return a*=b;
- }
- inline
- Weights operator*(double b, Weights a) {
- return a*=b;
- }
- inline
- Weights operator/(Weights a, Weights const & b) {
- return a/=b;
- }
- inline
- Weights operator/(Weights a, double b) {
- return a/=b;
- }
-}
+#include "HEJ/Parameters.hh"
diff --git a/include/HEJ/event_types.hh b/include/HEJ/event_types.hh
index d2e6097..ac85fd6 100644
--- a/include/HEJ/event_types.hh
+++ b/include/HEJ/event_types.hh
@@ -1,80 +1,82 @@
/** \file
* \brief Define different types of events.
*
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#pragma once
#include "HEJ/utility.hh"
namespace HEJ{
//! Namespace for event types
namespace event_type{
//! Possible event types
enum EventType: size_t{
FKL, /**< FKL-type event */
unordered_backward, /**< event with unordered backward emission */
unordered_forward, /**< event with unordered forward emission */
extremal_qqxb, /**< event with a backward extremal qqbar */
extremal_qqxf, /**< event with a forward extremal qqbar */
central_qqx, /**< event with a central qqbar */
nonHEJ, /**< event configuration not covered by HEJ */
no_2_jets, /**< event with less than two jets */
bad_final_state, /**< event with an unsupported final state */
unob = unordered_backward,
unof = unordered_forward,
qqxexb = extremal_qqxb,
qqxexf = extremal_qqxf,
qqxmid = central_qqx,
first_type = FKL,
last_type = bad_final_state
};
//! Event type names
/**
* For example, names[FKL] is the string "FKL"
*/
static constexpr auto names = make_array(
"FKL",
"unordered backward",
"unordered forward",
"extremal qqbar backward",
"extremal qqbar forward",
"central qqbar",
"nonHEJ",
"no 2 jets",
"bad final state"
);
+ //! Returns True for a HEJ \ref event_type::EventType "EventType"
inline
bool is_HEJ(EventType type) {
switch(type) {
case FKL:
case unordered_backward:
case unordered_forward:
case extremal_qqxb:
case extremal_qqxf:
case central_qqx:
return true;
default:
return false;
}
}
+ //! Returns True for an unordered \ref event_type::EventType "EventType"
inline
bool is_uno(EventType type) {
return type == unordered_backward || type == unordered_forward;
}
inline
bool is_qqx(EventType type) {
return type == extremal_qqxb || type == extremal_qqxf || type == central_qqx;
}
}
}
diff --git a/src/Event.cc b/src/Event.cc
index 6f04831..002d6fb 100644
--- a/src/Event.cc
+++ b/src/Event.cc
@@ -1,692 +1,795 @@
/**
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#include "HEJ/Event.hh"
#include <algorithm>
#include <assert.h>
#include <numeric>
#include <utility>
#include "LHEF/LHEF.h"
#include "fastjet/JetDefinition.hh"
+#include "HEJ/Constants.hh"
#include "HEJ/exceptions.hh"
#include "HEJ/PDG_codes.hh"
namespace HEJ{
namespace{
constexpr int status_in = -1;
constexpr int status_decayed = 2;
constexpr int status_out = 1;
/// @name helper functions to determine event type
//@{
/**
* \brief check if final state valid for HEJ
*
* check if there is at most one photon, W, H, Z in the final state
* and all the rest are quarks or gluons
*/
bool final_state_ok(std::vector<Particle> const & outgoing){
bool has_AWZH_boson = false;
for(auto const & out: outgoing){
if(is_AWZH_boson(out.type)){
if(has_AWZH_boson) return false;
has_AWZH_boson = true;
}
else if(! is_parton(out.type)) return false;
}
return true;
}
template<class Iterator>
Iterator remove_AWZH(Iterator begin, Iterator end){
return std::remove_if(
begin, end, [](Particle const & p){return is_AWZH_boson(p);}
);
}
template<class Iterator>
bool valid_outgoing(Iterator begin, Iterator end){
return std::distance(begin, end) >= 2
&& std::is_sorted(begin, end, rapidity_less{})
&& std::count_if(
begin, end, [](Particle const & s){return is_AWZH_boson(s);}
) < 2;
}
/**
* \brief function which determines if type change is consistent with W emission.
* @param in incoming Particle
* @param out outgoing Particle
*
* Ensures that change type of quark line is possible by a flavour changing
* W emission.
*/
bool is_W_Current(ParticleID in, ParticleID out){
if((in==1 && out==2)||(in==2 && out==1)){
return true;
}
else if((in==-1 && out==-2)||(in==-2 && out==-1)){
return true;
}
else if((in==3 && out==4)||(in==4 && out==3)){
return true;
}
else if((in==-3 && out==-4)||(in==-4 && out==-3)){
return true;
}
else{
return false;
}
}
/**
* \brief checks if particle type remains same from incoming to outgoing
* @param in incoming Particle
* @param out outgoing Particle
*/
bool is_Pure_Current(ParticleID in, ParticleID out){
if(abs(in)<=6 || in==21) return (in==out);
else return false;
}
// @note that this changes the outgoing range!
template<class ConstIterator, class Iterator>
bool is_FKL(
ConstIterator begin_incoming, ConstIterator end_incoming,
Iterator begin_outgoing, Iterator end_outgoing
){
assert(std::distance(begin_incoming, end_incoming) == 2);
assert(std::distance(begin_outgoing, end_outgoing) >= 2);
// One photon, W, H, Z in the final state is allowed.
// Remove it for remaining tests,
end_outgoing = remove_AWZH(begin_outgoing, end_outgoing);
if(std::all_of(
begin_outgoing + 1, end_outgoing - 1,
[](Particle const & p){ return p.type == pid::gluon; })
){
// Test if this is a standard FKL configuration.
if (is_Pure_Current(begin_incoming->type, begin_outgoing->type)
&& is_Pure_Current((end_incoming-1)->type, (end_outgoing-1)->type)){
return true;
}
}
return false;
}
template<class ConstIterator, class Iterator>
bool is_W_FKL(
ConstIterator begin_incoming, ConstIterator end_incoming,
Iterator begin_outgoing, Iterator end_outgoing
){
assert(std::distance(begin_incoming, end_incoming) == 2);
assert(std::distance(begin_outgoing, end_outgoing) >= 2);
// One photon, W, H, Z in the final state is allowed.
// Remove it for remaining tests,
end_outgoing = remove_AWZH(begin_outgoing, end_outgoing);
if(std::all_of(
begin_outgoing + 1, end_outgoing - 1,
[](Particle const & p){ return p.type == pid::gluon; })
){
// Test if this is a standard FKL configuration.
if(is_W_Current(begin_incoming->type, begin_outgoing->type)
&& is_Pure_Current((end_incoming-1)->type, (end_outgoing-1)->type)){
return true;
}
else if(is_Pure_Current(begin_incoming->type, begin_outgoing->type)
&& is_W_Current((end_incoming-1)->type, (end_outgoing-1)->type)){
return true;
}
}
return false;
}
bool is_FKL(
std::array<Particle, 2> const & incoming,
std::vector<Particle> outgoing
){
assert(std::is_sorted(begin(incoming), end(incoming), pz_less{}));
assert(valid_outgoing(begin(outgoing), end(outgoing)));
const auto WEmit = std::find_if(
begin(outgoing), end(outgoing),
[](Particle const & s){ return abs(s.type) == pid::Wp; }
);
if (abs(WEmit->type) == pid::Wp){
return is_W_FKL(
begin(incoming), end(incoming),
begin(outgoing), end(outgoing)
);
}
else{
return is_FKL(
begin(incoming), end(incoming),
begin(outgoing), end(outgoing)
);
}
}
bool has_2_jets(Event const & event){
return event.jets().size() >= 2;
}
/**
* \brief Checks whether event is unordered backwards
* @param ev Event
* @returns Is Event Unordered Backwards
*
* - Checks there is more than 3 constuents in the final state
* - Checks there is more than 3 jets
* - Checks the most backwards parton is a gluon
* - Checks the most forwards jet is not a gluon
* - Checks the rest of the event is FKL
* - Checks the second most backwards is not a different boson
* - Checks the unordered gluon actually forms a jet
*/
bool is_unordered_backward(Event const & ev){
auto const & in = ev.incoming();
auto const & out = ev.outgoing();
assert(std::is_sorted(begin(in), end(in), pz_less{}));
assert(valid_outgoing(begin(out), end(out)));
if(out.size() < 3) return false;
if(ev.jets().size() < 3) return false;
if(in.front().type == pid::gluon) return false;
if(out.front().type != pid::gluon) return false;
// When skipping the unordered emission
// the remainder should be a regular FKL event,
// except that the (new) first outgoing particle must not be a A,W,Z,H.
const auto FKL_begin = next(begin(out));
if(is_AWZH_boson(*FKL_begin)) return false;
if(!is_FKL(in, {FKL_begin, end(out)})) return false;
// check that the unordered gluon forms an extra jet
const auto jets = sorted_by_rapidity(ev.jets());
const auto indices = ev.particle_jet_indices({jets.front()});
return indices[0] >= 0 && indices[1] == -1;
}
/**
* \brief Checks for a forward unordered gluon emission
* @param ev Event
* @returns Is the event a forward unordered emission
*
* \see is_unordered_backward
*/
bool is_unordered_forward(Event const & ev){
auto const & in = ev.incoming();
auto const & out = ev.outgoing();
assert(std::is_sorted(begin(in), end(in), pz_less{}));
assert(valid_outgoing(begin(out), end(out)));
if(out.size() < 3) return false;
if(ev.jets().size() < 3) return false;
if(in.back().type == pid::gluon) return false;
if(out.back().type != pid::gluon) return false;
// When skipping the unordered emission
// the remainder should be a regular FKL event,
// except that the (new) last outgoing particle must not be a A,W,Z,H.
const auto FKL_end = prev(end(out));
if(is_AWZH_boson(*prev(FKL_end))) return false;
if(!is_FKL(in, {begin(out), FKL_end})) return false;
// check that the unordered gluon forms an extra jet
const auto jets = sorted_by_rapidity(ev.jets());
const auto indices = ev.particle_jet_indices({jets.back()});
return indices.back() >= 0 && indices[indices.size()-2] == -1;
}
/**
* \brief Checks for a forward extremal qqx
* @param ev Event
* @returns Is the event a forward extremal qqx event
*
* Checks there is 3 or more than 3 constituents in the final state
* Checks there is 3 or more than 3 jets
* Checks most forwards incoming is gluon
* Checks most extremal particle is not a Higgs (either direction)
* Checks the second most forwards particle is not Higgs boson
* Checks the most forwards parton is a either quark or anti-quark.
* Checks the second most forwards parton is anti-quark or quark.
* Checks the qqbar pair form 2 separate jets.
*/
bool is_Ex_qqxf(Event const & ev){
auto const & in = ev.incoming();
auto const & out = ev.outgoing();
assert(std::is_sorted(begin(in), end(in), pz_less{}));
assert(valid_outgoing(begin(out), end(out)));
int fkl_end=2;
if(out.size() < 3) return false;
if(ev.jets().size() < 3) return false;
if(in.back().type != pid::gluon) return false;
if(out.back().type == pid::Higgs || out.front().type == pid::Higgs
|| out.rbegin()[1].type == pid::Higgs) return false;
// if extremal AWZ
if(is_AWZ_boson(out.back())){ // if extremal AWZ
fkl_end++;
if (is_quark(out.rbegin()[1])){ //if second quark
if (!(is_antiquark(out.rbegin()[2]))) return false;// third must be anti-quark
}
else if (is_antiquark(out.rbegin()[1])){ //if second anti-quark
if (!(is_quark(out.rbegin()[2]))) return false;// third must be quark
}
else return false;
}
else if (is_quark(out.rbegin()[0])){ //if extremal quark
if(is_AWZ_boson(out.rbegin()[1])){ // if second AWZ
fkl_end++;
if (!(is_antiquark(out.rbegin()[2]))) return false;// third must be anti-quark
}
else if (!(is_antiquark(out.rbegin()[1]))) return false;// second must be anti-quark
}
else if (is_antiquark(out.rbegin()[0])){ //if extremal anti-quark
if(is_AWZ_boson(out.rbegin()[1])){ // if second AWZ
fkl_end++;
if (!(is_quark(out.rbegin()[2]))) return false;// third must be quark
}
else if (!(is_quark(out.rbegin()[1]))) return false;// second must be quark
}
else return false;
// When skipping the qqbar
// New last outgoing particle must not be a Higgs
if (out.rbegin()[fkl_end].type == pid::Higgs) return false;
const auto jets = fastjet::sorted_by_rapidity(ev.jets());
const auto indices = ev.particle_jet_indices({jets});
// Ensure qqbar pair are in separate jets
if(indices[indices.size()-2] != indices[indices.size()-1]-1) return false;
// Opposite current should be logical to process
if (is_AWZ_boson(out.front().type)){
return (is_Pure_Current(in.front().type, out[1].type)
|| is_W_Current(in.front().type,out[1].type));
}
else
return (is_Pure_Current(in.front().type, out[0].type)
|| is_W_Current(in.front().type,out[0].type));
}
/**
* \brief Checks for a backward extremal qqx
* @param ev Event
* @returns Is the event a backward extremal qqx event
*
* Checks there is 3 or more than 3 constituents in the final state
* Checks there is 3 or more than 3 jets
* Checks most backwards incoming is gluon
* Checks most extremal particle is not a Higgs (either direction) y
* Checks the second most backwards particle is not Higgs boson y
* Checks the most backwards parton is a either quark or anti-quark. y
* Checks the second most backwards parton is anti-quark or quark. y
* Checks the qqbar pair form 2 separate jets.
*/
bool is_Ex_qqxb(Event const & ev){
auto const & in = ev.incoming();
auto const & out = ev.outgoing();
assert(std::is_sorted(begin(in), end(in), pz_less{}));
assert(valid_outgoing(begin(out), end(out)));
int fkl_start=2;
if(out.size() < 3) return false;
if(ev.jets().size() < 3) return false;
if(in.front().type != pid::gluon) return false;
if(out.back().type == pid::Higgs || out.front().type == pid::Higgs
|| out[1].type == pid::Higgs) return false;
if(is_AWZ_boson(out.front())){ // if extremal AWZ
fkl_start++;
if (is_quark(out[1])){ //if second quark
if (!(is_antiquark(out[2]))) return false;// third must be anti-quark
}
else if (is_antiquark(out[1])){ //if second anti-quark
if (!(is_quark(out[2]))) return false;// third must be quark
}
else return false;
}
else if (is_quark(out[0])){ // if extremal quark
if(is_AWZ_boson(out[1])){ // if second AWZ
fkl_start++;
if (!(is_antiquark(out[2]))) return false;// third must be anti-quark
}
else if (!(is_antiquark(out[1]))) return false;// second must be anti-quark
}
else if (is_antiquark(out[0])){ //if extremal anti-quark
if(is_AWZ_boson(out[1])){ // if second AWZ
fkl_start++;
if (!(is_quark(out[2]))) return false;// third must be quark
}
else if (!(is_quark(out[1]))) return false;// second must be quark
}
else return false;
// When skipping the qqbar
// New last outgoing particle must not be a Higgs.
if (out[fkl_start].type == pid::Higgs) return false;
const auto jets = fastjet::sorted_by_rapidity(ev.jets());
const auto indices = ev.particle_jet_indices({jets});
// Ensure qqbar pair form separate jets.
if(indices[0] != indices[1]-1) return false;
// Other current should be logical to process
if (is_AWZ_boson(out.back())){
return (is_Pure_Current(in.back().type, out.rbegin()[1].type)
|| is_W_Current(in.back().type,out.rbegin()[1].type));
}
else
return (is_Pure_Current(in.back().type, out.rbegin()[0].type)
|| is_W_Current(in.back().type, out.rbegin()[0].type));
}
/**
* \brief Checks for a central qqx
* @param ev Event
* @returns Is the event a central extremal qqx event
*
* Checks there is 4 or more than 4 constuents in the final state
* Checks there is 4 or more than 4 jets
* Checks most extremal particle is not a Higgs (either direction) y
* Checks for a central quark in the outgoing states
* Checks for adjacent anti-quark parton. (allowing for AWZ boson emission between)
* Checks external currents are logically sound.
*/
bool is_Mid_qqx(Event const & ev){
auto const & in = ev.incoming();
auto const & out = ev.outgoing();
assert(std::is_sorted(begin(in), end(in), pz_less{}));
assert(valid_outgoing(begin(out), end(out)));
if(out.size() < 4) return false;
if(ev.jets().size() < 4) return false;
if(out.back().type == pid::Higgs || out.front().type == pid::Higgs)
return false;
size_t start_FKL=0;
size_t end_FKL=0;
if (is_AWZ_boson(out.back())){
end_FKL++;
}
if (is_AWZ_boson(out.front())){
start_FKL++;
}
if ((is_Pure_Current(in.back().type,out.rbegin()[end_FKL].type)
&& is_Pure_Current(in.front().type,out[start_FKL].type))){
//nothing to do
}
else if (is_W_Current(in.back().type,out.rbegin()[end_FKL].type)
&& is_Pure_Current(in.front().type,out[start_FKL].type)){
//nothing to do
}
else if (!(is_Pure_Current(in.back().type,out.rbegin()[end_FKL].type)
&& is_W_Current(in.front().type,out[start_FKL].type))){
return false;
}
const auto jets = fastjet::sorted_by_rapidity(ev.jets());
const auto indices = ev.particle_jet_indices({jets});
auto const out_partons = filter_partons(out);
for (size_t i = 1; i<out_partons.size()-2; i++){
if ((is_quark(out_partons[i]) && (is_antiquark(out_partons[i+1])))
|| (is_antiquark(out_partons[i]) && (is_quark(out_partons[i+1])))){
return (indices[i+1] == indices[i]+1 && indices[i] != -1);
}
}
return false;
}
using event_type::EventType;
EventType classify(Event const & ev){
if(! final_state_ok(ev.outgoing()))
return EventType::bad_final_state;
if(! has_2_jets(ev))
return EventType::no_2_jets;
if(is_FKL(ev.incoming(), ev.outgoing()))
return EventType::FKL;
if(is_unordered_backward(ev))
return EventType::unordered_backward;
if(is_unordered_forward(ev))
return EventType::unordered_forward;
if(is_Ex_qqxb(ev))
return EventType::extremal_qqxb;
if(is_Ex_qqxf(ev))
return EventType::extremal_qqxf;
if(is_Mid_qqx(ev))
return EventType::central_qqx;
return EventType::nonHEJ;
}
//@}
Particle extract_particle(LHEF::HEPEUP const & hepeup, int i){
- return Particle{
- static_cast<ParticleID>(hepeup.IDUP[i]),
- fastjet::PseudoJet{
- hepeup.PUP[i][0], hepeup.PUP[i][1],
- hepeup.PUP[i][2], hepeup.PUP[i][3]
- }
+ const ParticleID id = static_cast<ParticleID>(hepeup.IDUP[i]);
+ const fastjet::PseudoJet momentum{
+ hepeup.PUP[i][0], hepeup.PUP[i][1],
+ hepeup.PUP[i][2], hepeup.PUP[i][3]
};
+ if(is_parton(id))
+ return Particle{ id, std::move(momentum), hepeup.ICOLUP[i] };
+ return Particle{ id, std::move(momentum), {} };
}
bool is_decay_product(std::pair<int, int> const & mothers){
if(mothers.first == 0) return false;
return mothers.second == 0 || mothers.first == mothers.second;
}
} // namespace anonymous
- UnclusteredEvent::UnclusteredEvent(LHEF::HEPEUP const & hepeup):
- central(EventParameters{
+ Event::EventData::EventData(LHEF::HEPEUP const & hepeup){
+ parameters.central = EventParameters{
hepeup.scales.mur, hepeup.scales.muf, hepeup.weight()
- })
- {
+ };
size_t in_idx = 0;
for (int i = 0; i < hepeup.NUP; ++i) {
// skip decay products
// we will add them later on, but we have to ensure that
// the decayed particle is added before
if(is_decay_product(hepeup.MOTHUP[i])) continue;
auto particle = extract_particle(hepeup, i);
// needed to identify mother particles for decay products
particle.p.set_user_index(i+1);
if(hepeup.ISTUP[i] == status_in){
if(in_idx > incoming.size()) {
throw std::invalid_argument{
"Event has too many incoming particles"
};
}
incoming[in_idx++] = std::move(particle);
}
else outgoing.emplace_back(std::move(particle));
}
// add decay products
for (int i = 0; i < hepeup.NUP; ++i) {
if(!is_decay_product(hepeup.MOTHUP[i])) continue;
const int mother_id = hepeup.MOTHUP[i].first;
const auto mother = std::find_if(
begin(outgoing), end(outgoing),
[mother_id](Particle const & particle){
return particle.p.user_index() == mother_id;
}
);
if(mother == end(outgoing)){
throw std::invalid_argument{"invalid decay product parent"};
}
const int mother_idx = std::distance(begin(outgoing), mother);
assert(mother_idx >= 0);
decays[mother_idx].emplace_back(extract_particle(hepeup, i));
}
}
Event::Event(
- UnclusteredEvent ev,
- fastjet::JetDefinition const & jet_def, double min_jet_pt
+ UnclusteredEvent const & ev,
+ fastjet::JetDefinition const & jet_def, double const min_jet_pt
):
- ev_{std::move(ev)},
- cs_{to_PseudoJet(filter_partons(ev_.outgoing)), jet_def},
- min_jet_pt_{min_jet_pt}
- {
+ Event( Event::EventData{
+ ev.incoming, ev.outgoing, ev.decays,
+ Parameters<EventParameters>{ev.central, ev.variations}
+ }.cluster(jet_def, min_jet_pt) )
+ {}
+
+ //! @TODO remove in HEJ 2.3.0
+ UnclusteredEvent::UnclusteredEvent(LHEF::HEPEUP const & hepeup){
+ Event::EventData const evData{hepeup};
+ incoming = evData.incoming;
+ outgoing = evData.outgoing;
+ decays = evData.decays;
+ central = evData.parameters.central;
+ variations = evData.parameters.variations;
+ }
+
+ void Event::EventData::sort(){
// sort particles
std::sort(
- begin(ev_.incoming), end(ev_.incoming),
+ begin(incoming), end(incoming),
[](Particle o1, Particle o2){return o1.p.pz()<o2.p.pz();}
);
- auto old_outgoing = std::move(ev_.outgoing);
+ auto old_outgoing = std::move(outgoing);
std::vector<size_t> idx(old_outgoing.size());
std::iota(idx.begin(), idx.end(), 0);
std::sort(idx.begin(), idx.end(), [&old_outgoing](size_t i, size_t j){
return old_outgoing[i].rapidity() < old_outgoing[j].rapidity();
});
- ev_.outgoing.clear();
- ev_.outgoing.reserve(old_outgoing.size());
+ outgoing.clear();
+ outgoing.reserve(old_outgoing.size());
for(size_t i: idx) {
- ev_.outgoing.emplace_back(std::move(old_outgoing[i]));
+ outgoing.emplace_back(std::move(old_outgoing[i]));
}
// find decays again
- if(!ev_.decays.empty()){
- auto old_decays = std::move(ev_.decays);
- ev_.decays.clear();
+ if(!decays.empty()){
+ auto old_decays = std::move(decays);
+ decays.clear();
for(size_t i=0; i<idx.size(); ++i) {
auto decay = old_decays.find(idx[i]);
if(decay != old_decays.end())
- ev_.decays.emplace(i, std::move(decay->second));
+ decays.emplace(i, std::move(decay->second));
}
- assert(old_decays.size() == ev_.decays.size());
+ assert(old_decays.size() == decays.size());
}
+ }
- // classify event
- type_ = classify(*this);
+ Event Event::EventData::cluster(
+ fastjet::JetDefinition const & jet_def, double const min_jet_pt
+ ){
+ sort();
+ Event ev{ std::move(incoming), std::move(outgoing), std::move(decays),
+ std::move(parameters),
+ jet_def, min_jet_pt
+ };
+ assert(std::is_sorted(begin(ev.outgoing_), end(ev.outgoing_),
+ rapidity_less{}));
+ ev.type_ = classify(ev);
+ return ev;
+ }
- assert(std::is_sorted(begin(outgoing()), end(outgoing()), rapidity_less{}));
+ namespace {
+ void connect_incoming(Particle & in, int & colour, int & anti_colour){
+ in.colour = std::make_pair(anti_colour, colour);
+ // gluon
+ if(in.type == pid::gluon)
+ return;
+ if(in.type > 0){
+ // quark
+ assert(is_quark(in));
+ in.colour->second = 0;
+ colour*=-1;
+ return;
+ }
+ // anti-quark
+ assert(is_antiquark(in));
+ in.colour->first = 0;
+ anti_colour*=-1;
+ return;
+ }
}
+ bool Event::generate_colours(RNG & ran){
+ // generate only for HEJ events
+ if(!event_type::is_HEJ(type()))
+ return false;
+ assert(std::is_sorted(
+ begin(outgoing()), end(outgoing()), rapidity_less{}));
+ assert(incoming()[0].pz() < incoming()[1].pz());
+
+ // positive (anti-)colour -> can connect
+ // negative (anti-)colour -> not available/used up by (anti-)quark
+ int colour = COLOUR_OFFSET;
+ int anti_colour = colour+1;
+ // initialise first
+ connect_incoming(incoming_[0], colour, anti_colour);
+
+ for(auto & part: outgoing_){
+ assert(colour>0 || anti_colour>0);
+ if(part.type == ParticleID::gluon){
+ // gluon
+ if(colour>0 && anti_colour>0){
+ // on g line => connect to colour OR anti-colour (random)
+ if(ran.flat() < 0.5){
+ part.colour = std::make_pair(colour+2,colour);
+ colour+=2;
+ } else {
+ part.colour = std::make_pair(anti_colour, anti_colour+2);
+ anti_colour+=2;
+ }
+ } else if(colour > 0){
+ // on q line => connect to available colour
+ part.colour = std::make_pair(colour+2, colour);
+ colour+=2;
+ } else {
+ assert(colour<0 && anti_colour>0);
+ // on qx line => connect to available anti-colour
+ part.colour = std::make_pair(anti_colour, anti_colour+2);
+ anti_colour+=2;
+ }
+ } else if(is_quark(part)) {
+ // quark
+ assert(anti_colour>0);
+ if(colour>0){
+ // on g line => connect and remove anti-colour
+ part.colour = std::make_pair(anti_colour, 0);
+ anti_colour+=2;
+ anti_colour*=-1;
+ } else {
+ // on qx line => new colour
+ colour*=-1;
+ part.colour = std::make_pair(colour, 0);
+ }
+ } else if(is_antiquark(part)) {
+ // anti-quark
+ assert(colour>0);
+ if(anti_colour>0){
+ // on g line => connect and remove colour
+ part.colour = std::make_pair(0, colour);
+ colour+=2;
+ colour*=-1;
+ } else {
+ // on q line => new anti-colour
+ anti_colour*=-1;
+ part.colour = std::make_pair(0, anti_colour);
+ }
+ }
+ // else not a parton
+ }
+ // Connect last
+ connect_incoming(incoming_[1], anti_colour, colour);
+ return true;
+ } // generate_colours
+
std::vector<fastjet::PseudoJet> Event::jets() const{
return cs_.inclusive_jets(min_jet_pt_);
}
/**
* \brief Returns the invarient mass of the event
* @param ev Event
* @returns s hat
*
* Makes use of the FastJet PseudoJet function m2().
* Applies this function to the sum of the incoming partons.
*/
double shat(Event const & ev){
return (ev.incoming()[0].p + ev.incoming()[1].p).m2();
}
- namespace{
- // colour flow according to Les Houches standard
- // TODO: stub
- std::vector<std::pair<int, int>> colour_flow(
- std::array<Particle, 2> const & incoming,
- std::vector<Particle> const & outgoing
- ){
- std::vector<std::pair<int, int>> result(
- incoming.size() + outgoing.size()
- );
- for(auto & col: result){
- col = std::make_pair(-1, -1);
- }
- return result;
- }
- }
-
LHEF::HEPEUP to_HEPEUP(Event const & event, LHEF::HEPRUP * heprup){
LHEF::HEPEUP result;
result.heprup = heprup;
result.weights = {{event.central().weight, nullptr}};
for(auto const & var: event.variations()){
result.weights.emplace_back(var.weight, nullptr);
}
size_t num_particles = event.incoming().size() + event.outgoing().size();
for(auto const & decay: event.decays()) num_particles += decay.second.size();
result.NUP = num_particles;
// the following entries are pretty much meaningless
result.IDPRUP = event.type()+1; // event ID
result.AQEDUP = 1./128.; // alpha_EW
//result.AQCDUP = 0.118 // alpha_QCD
// end meaningless part
result.XWGTUP = event.central().weight;
result.SCALUP = event.central().muf;
result.scales.muf = event.central().muf;
result.scales.mur = event.central().mur;
result.scales.SCALUP = event.central().muf;
result.pdfinfo.p1 = event.incoming().front().type;
result.pdfinfo.p2 = event.incoming().back().type;
result.pdfinfo.scale = event.central().muf;
+
+ result.IDUP.reserve(num_particles); // PID
+ result.ISTUP.reserve(num_particles); // status (in, out, decay)
+ result.PUP.reserve(num_particles); // momentum
+ result.MOTHUP.reserve(num_particles); // index mother particle
+ result.ICOLUP.reserve(num_particles); // colour
+ // incoming
for(Particle const & in: event.incoming()){
result.IDUP.emplace_back(in.type);
result.ISTUP.emplace_back(status_in);
result.PUP.push_back({in.p[0], in.p[1], in.p[2], in.p[3], in.p.m()});
result.MOTHUP.emplace_back(0, 0);
+ assert(in.colour);
+ result.ICOLUP.emplace_back(*in.colour);
}
+ // outgoing
for(size_t i = 0; i < event.outgoing().size(); ++i){
Particle const & out = event.outgoing()[i];
result.IDUP.emplace_back(out.type);
const int status = event.decays().count(i)?status_decayed:status_out;
result.ISTUP.emplace_back(status);
result.PUP.push_back({out.p[0], out.p[1], out.p[2], out.p[3], out.p.m()});
result.MOTHUP.emplace_back(1, 2);
+ if(out.colour)
+ result.ICOLUP.emplace_back(*out.colour);
+ else{
+ assert(is_AWZH_boson(out));
+ result.ICOLUP.emplace_back(std::make_pair(0,0));
+ }
}
- result.ICOLUP = colour_flow(
- event.incoming(), filter_partons(event.outgoing())
- );
- if(result.ICOLUP.size() < num_particles){
- const size_t AWZH_boson_idx = std::find_if(
- begin(event.outgoing()), end(event.outgoing()),
- [](Particle const & s){ return is_AWZH_boson(s); }
- ) - begin(event.outgoing()) + event.incoming().size();
- assert(AWZH_boson_idx <= result.ICOLUP.size());
- result.ICOLUP.insert(
- begin(result.ICOLUP) + AWZH_boson_idx,
- std::make_pair(0,0)
- );
- }
+ // decays
for(auto const & decay: event.decays()){
for(auto const out: decay.second){
result.IDUP.emplace_back(out.type);
result.ISTUP.emplace_back(status_out);
result.PUP.push_back({out.p[0], out.p[1], out.p[2], out.p[3], out.p.m()});
const size_t mother_idx = 1 + event.incoming().size() + decay.first;
result.MOTHUP.emplace_back(mother_idx, mother_idx);
result.ICOLUP.emplace_back(0,0);
}
}
+
assert(result.ICOLUP.size() == num_particles);
static constexpr double unknown_spin = 9.; //per Les Houches accord
result.VTIMUP = std::vector<double>(num_particles, unknown_spin);
result.SPINUP = result.VTIMUP;
return result;
}
}
diff --git a/src/EventReweighter.cc b/src/EventReweighter.cc
index 28cebd9..fadb50d 100644
--- a/src/EventReweighter.cc
+++ b/src/EventReweighter.cc
@@ -1,333 +1,324 @@
/**
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#include "HEJ/EventReweighter.hh"
#include <algorithm>
#include <assert.h>
#include <limits>
#include <math.h>
#include <stddef.h>
#include <string>
#include <unordered_map>
#include "fastjet/ClusterSequence.hh"
#include "LHEF/LHEF.h"
#include "HEJ/Event.hh"
#include "HEJ/exceptions.hh"
#include "HEJ/Particle.hh"
#include "HEJ/PDG_codes.hh"
#include "HEJ/PhaseSpacePoint.hh"
-#include "HEJ/Weights.hh"
namespace HEJ{
using EventType = event_type::EventType;
namespace {
static_assert(
std::numeric_limits<double>::has_quiet_NaN,
"no quiet NaN for double"
);
constexpr double NaN = std::numeric_limits<double>::quiet_NaN();
- UnclusteredEvent to_UnclusteredEvent(PhaseSpacePoint const & psp){
- UnclusteredEvent result;
- result.incoming = psp.incoming();
- std::sort(
- begin(result.incoming), end(result.incoming),
- [](Particle o1, Particle o2){return o1.p.pz()<o2.p.pz();}
- );
+ Event::EventData to_EventData(PhaseSpacePoint const & psp){
+ Event::EventData result;
+ result.incoming=psp.incoming();
assert(result.incoming.size() == 2);
- result.outgoing = psp.outgoing();
+ result.outgoing=psp.outgoing();
+ // technically Event::EventData doesn't have to be sorted,
+ // but PhaseSpacePoint should be anyway
assert(
std::is_sorted(
begin(result.outgoing), end(result.outgoing),
rapidity_less{}
)
);
assert(result.outgoing.size() >= 2);
result.decays = psp.decays();
- result.central.mur = NaN;
- result.central.muf = NaN;
- result.central.weight = psp.weight();
+ result.parameters.central = {NaN, NaN, psp.weight()};
return result;
}
} // namespace anonymous
EventReweighter::EventReweighter(
LHEF::HEPRUP const & heprup,
ScaleGenerator scale_gen,
EventReweighterConfig conf,
HEJ::RNG & ran
):
EventReweighter{
HEJ::Beam{
heprup.EBMUP.first,
{{
static_cast<HEJ::ParticleID>(heprup.IDBMUP.first),
static_cast<HEJ::ParticleID>(heprup.IDBMUP.second)
}}
},
heprup.PDFSUP.first,
std::move(scale_gen),
std::move(conf),
ran
}
{
if(heprup.EBMUP.second != E_beam_){
throw std::invalid_argument(
"asymmetric beam: " + std::to_string(E_beam_)
+ " ---> <--- " + std::to_string(heprup.EBMUP.second)
);
};
if(heprup.PDFSUP.second != pdf_.id()){
throw std::invalid_argument(
"conflicting PDF ids: " + std::to_string(pdf_.id())
+ " vs. " + std::to_string(heprup.PDFSUP.second)
);
}
}
EventReweighter::EventReweighter(
Beam beam,
int pdf_id,
ScaleGenerator scale_gen,
EventReweighterConfig conf,
HEJ::RNG & ran
):
param_{std::move(conf)},
E_beam_{beam.E},
pdf_{pdf_id, beam.type.front(), beam.type.back()},
MEt2_{
[this](double mu){ return pdf_.Halphas(mu); },
param_.ME_config
},
scale_gen_(std::move(scale_gen)),
ran_{ran}
{}
PDF const & EventReweighter::pdf() const{
return pdf_;
}
std::vector<Event> EventReweighter::reweight(
Event const & input_ev, int num_events
){
auto res_events = gen_res_events(input_ev, num_events);
if(res_events.empty()) return {};
for(auto & event: res_events) event = scale_gen_(event);
return rescale(input_ev, std::move(res_events));
}
/**
* \brief main generation/reweighting function:
* generate phase space points and divide out Born factors
*/
std::vector<Event> EventReweighter::gen_res_events(
Event const & ev,
int phase_space_points
){
assert(ev.variations().empty());
switch(param_.treat.at(ev.type())){
case EventTreatment::discard: return {};
case EventTreatment::keep:
if(! jets_pass_resummation_cuts(ev)) return {};
else return {ev};
default:;
}
const double Born_shat = shat(ev);
std::vector<Event> resummation_events;
for(int psp_number = 0; psp_number < phase_space_points; ++psp_number){
PhaseSpacePoint psp{ev, param_.psp_config, ran_};
if(psp.weight() == 0.) continue;
if(psp.incoming()[0].E() > E_beam_ || psp.incoming()[1].E() > E_beam_) continue;
resummation_events.emplace_back(
- to_UnclusteredEvent(std::move(psp)),
+ to_EventData( std::move(psp) ).cluster(
param_.jet_param.def, param_.jet_param.min_pt
+ )
);
auto & new_event = resummation_events.back();
+ assert(new_event.type() == ev.type());
+ new_event.generate_colours(ran_);
assert(new_event.variations().empty());
new_event.central().mur = ev.central().mur;
new_event.central().muf = ev.central().muf;
const double resum_shat = shat(new_event);
new_event.central().weight *= ev.central().weight*Born_shat*Born_shat/
(phase_space_points*resum_shat*resum_shat);
}
return resummation_events;
}
std::vector<Event> EventReweighter::rescale(
Event const & Born_ev,
std::vector<Event> events
) const{
const double Born_pdf = pdf_factors(Born_ev).central;
const double Born_ME = tree_matrix_element(Born_ev);
for(auto & cur_event: events){
const auto pdf = pdf_factors(cur_event);
assert(pdf.variations.size() == cur_event.variations().size());
const auto ME = matrix_elements(cur_event);
assert(ME.variations.size() == cur_event.variations().size());
- cur_event.central().weight *= pdf.central*ME.central/(Born_pdf*Born_ME);
- for(size_t i = 0; i < cur_event.variations().size(); ++i){
- cur_event.variations(i).weight *=
- pdf.variations[i]*ME.variations[i]/(Born_pdf*Born_ME);
- }
+ cur_event.parameters() *= pdf*ME/(Born_pdf*Born_ME);
}
return events;
};
/**
* \brief Do the Jets pass the resummation Cuts?
*
* @param ev Event in Question
* @returns 0 or 1 depending on if ev passes Jet Cuts
*/
bool EventReweighter::jets_pass_resummation_cuts(
Event const & ev
) const{
const auto out_as_PseudoJet = to_PseudoJet(filter_partons(ev.outgoing()));
fastjet::ClusterSequence cs{out_as_PseudoJet, param_.jet_param.def};
return cs.inclusive_jets(param_.jet_param.min_pt).size() == ev.jets().size();
}
-
-
/**
* \brief pdf_factors Function
*
* @param ev Event in Question
* @returns Event weights due to PDFs
*
* Calculates the Central value and the variation due
* to the PDF choice made.
*/
- Weights
- EventReweighter::pdf_factors(Event const & ev) const{
+ Weights EventReweighter::pdf_factors(Event const & ev) const{
auto const & a = ev.incoming().front();
auto const & b = ev.incoming().back();
const double xa = a.p.e()/E_beam_;
const double xb = b.p.e()/E_beam_;
Weights result;
std::unordered_map<double, double> known_pdf;
result.central =
pdf_.pdfpt(0,xa,ev.central().muf,a.type)*
pdf_.pdfpt(1,xb,ev.central().muf,b.type);
known_pdf.emplace(ev.central().muf, result.central);
result.variations.reserve(ev.variations().size());
for(auto const & ev_param: ev.variations()){
const double muf = ev_param.muf;
auto cur_pdf = known_pdf.find(muf);
if(cur_pdf == known_pdf.end()){
cur_pdf = known_pdf.emplace(
muf,
pdf_.pdfpt(0,xa,muf,a.type)*pdf_.pdfpt(1,xb,muf,b.type)
).first;
}
result.variations.emplace_back(cur_pdf->second);
}
assert(result.variations.size() == ev.variations().size());
return result;
}
/**
* \brief matrix_elements Function
*
* @param ev Event in question
* @returns Event Weights due to MatrixElements
*
* Calculates the Central value and the variation due
* to the Matrix Element.
*/
Weights
EventReweighter::matrix_elements(Event const & ev) const{
assert(param_.treat.count(ev.type()) > 0);
if(param_.treat.find(ev.type())->second == EventTreatment::keep){
return fixed_order_scale_ME(ev);
}
return MEt2_(ev);
}
/**
* \brief Computes the tree level matrix element
*
* @param ev Event in Question
* @returns HEJ approximation to Tree level Matrix Element
*
* This computes the HEJ approximation to the tree level FO
* Matrix element which is used within the LO weighting process.
*/
double EventReweighter::tree_matrix_element(Event const & ev) const{
assert(ev.variations().empty());
assert(param_.treat.count(ev.type()) > 0);
if(param_.treat.find(ev.type())->second == EventTreatment::keep){
return fixed_order_scale_ME(ev).central;
}
return MEt2_.tree(ev).central;
}
/**
* \brief Scale-dependent part of fixed-order matrix element
*
* @param ev Event in question
* @returns Scale variation due to FO-ME.
*
* This is only called to compute the scale variation for events where
* we don't do resummation (e.g. non-FKL).
* Since at tree level the scale dependence is just due to alpha_s,
* it is enough to return the alpha_s(mur) factors in the matrix element.
* The rest drops out in the ratio of (output event ME)/(input event ME),
* so we never have to compute it.
*/
Weights
EventReweighter::fixed_order_scale_ME(Event const & ev) const{
int alpha_s_power = 0;
for(auto const & part: ev.outgoing()){
if(is_parton(part))
++alpha_s_power;
else {
switch(part.type){
case pid::Higgs: {
alpha_s_power += 2;
break;
}
// TODO
case pid::Wp:{
break;
}
case pid::Wm:{
break;
}
case pid::photon:
case pid::Z:
default:
throw not_implemented("Emission of boson of unsupported type");
}
}
}
Weights result;
result.central = pow(pdf_.Halphas(ev.central().mur), alpha_s_power);
for(auto const & var: ev.variations()){
result.variations.emplace_back(
pow(pdf_.Halphas(var.mur), alpha_s_power)
);
}
return result;
}
} // namespace HEJ
diff --git a/src/PhaseSpacePoint.cc b/src/PhaseSpacePoint.cc
index 1d581f3..3e3e4e9 100644
--- a/src/PhaseSpacePoint.cc
+++ b/src/PhaseSpacePoint.cc
@@ -1,625 +1,625 @@
/**
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#include "HEJ/PhaseSpacePoint.hh"
#include <algorithm>
#include <assert.h>
#include <numeric>
#include <random>
#include "fastjet/ClusterSequence.hh"
#include "HEJ/Constants.hh"
#include "HEJ/Event.hh"
#include "HEJ/JetSplitter.hh"
#include "HEJ/kinematics.hh"
#include "HEJ/resummation_jet.hh"
#include "HEJ/utility.hh"
#include "HEJ/PDG_codes.hh"
#include "HEJ/event_types.hh"
namespace HEJ{
namespace {
constexpr int max_jet_user_idx = PhaseSpacePoint::ng_max;
bool is_nonjet_parton(fastjet::PseudoJet const & parton){
assert(parton.user_index() != -1);
return parton.user_index() > max_jet_user_idx;
}
bool is_jet_parton(fastjet::PseudoJet const & parton){
assert(parton.user_index() != -1);
return parton.user_index() <= max_jet_user_idx;
}
// user indices for partons with extremal rapidity
constexpr int qqxb_idx = -7;
constexpr int qqxf_idx = -6;
constexpr int unob_idx = -5;
constexpr int unof_idx = -4;
constexpr int backward_FKL_idx = -3;
constexpr int forward_FKL_idx = -2;
}
namespace {
double estimate_ng_mean(std::vector<fastjet::PseudoJet> const & Born_jets){
const double delta_y =
Born_jets.back().rapidity() - Born_jets.front().rapidity();
assert(delta_y > 0);
// Formula derived from fit in arXiv:1805.04446 (see Fig. 2)
return 0.975052*delta_y;
}
}
std::vector<fastjet::PseudoJet> PhaseSpacePoint::cluster_jets(
std::vector<fastjet::PseudoJet> const & partons
) const{
fastjet::ClusterSequence cs(partons, param_.jet_param.def);
return cs.inclusive_jets(param_.jet_param.min_pt);
}
bool PhaseSpacePoint::pass_resummation_cuts(
std::vector<fastjet::PseudoJet> const & jets
) const{
return cluster_jets(jets).size() == jets.size();
}
int PhaseSpacePoint::sample_ng(std::vector<fastjet::PseudoJet> const & Born_jets){
const double ng_mean = estimate_ng_mean(Born_jets);
std::poisson_distribution<int> dist(ng_mean);
const int ng = dist(ran_.get());
assert(ng >= 0);
assert(ng < ng_max);
weight_ *= std::tgamma(ng + 1)*std::exp(ng_mean)*std::pow(ng_mean, -ng);
return ng;
}
void PhaseSpacePoint::copy_AWZH_boson_from(Event const & event){
auto const & from = event.outgoing();
const auto AWZH_boson = std::find_if(
begin(from), end(from),
[](Particle const & p){ return is_AWZH_boson(p); }
);
if(AWZH_boson == end(from)) return;
auto insertion_point = std::lower_bound(
begin(outgoing_), end(outgoing_), *AWZH_boson, rapidity_less{}
);
outgoing_.insert(insertion_point, *AWZH_boson);
// copy decay products
const int idx = std::distance(begin(from), AWZH_boson);
assert(idx >= 0);
const auto decay_it = event.decays().find(idx);
if(decay_it != end(event.decays())){
const int new_idx = std::distance(begin(outgoing_), insertion_point);
assert(new_idx >= 0);
assert(outgoing_[new_idx].type == AWZH_boson->type);
decays_.emplace(new_idx, decay_it->second);
}
assert(std::is_sorted(begin(outgoing_), end(outgoing_), rapidity_less{}));
}
//! \brief relabels qqx-pair with its PDG IDs.
//*@param ev Born Event
//
// This function will label the qqx pair in a qqx event back to
// their original types from the input event.
void PhaseSpacePoint::label_qqx(Event const & event){
auto const & bornout = event.outgoing();
const auto backquark = std::find_if(
begin(bornout) + 1 - ((qqxb_)?1:0), end(bornout) - 1 + ((qqxf_)?1:0) ,
[](Particle const & s){ return (s.type != pid::gluon && is_parton(s.type)); }
);
assert(backquark->type !=pid::gluon);
if(backquark == end(bornout) || (backquark+1)->type==pid::gluon) weight_= 0;
auto partons = to_PseudoJet(filter_partons(outgoing_));
fastjet::ClusterSequence cs(partons, event.jet_def());
const auto jets = fastjet::sorted_by_rapidity(cs.inclusive_jets(event.min_jet_pt()));
const auto indices = cs.particle_jet_indices({jets});
assert(partons.size() == indices.size());
int qpart=0;
// Find Parton in res event closest to most backward qqx jet in born
for (size_t i=0; i<indices.size(); i++){
if( (indices[i] != -1) && indices[i]!=indices[i+1]
&& nearby_rap(backquark->rapidity(), partons[i].rapidity(), 0.1)){
qpart=i;
}
}
if (indices[qpart] == -1) weight_= 0;
else if (indices[qpart] == 0 && (!qqxb_)) weight_=0;
else if (indices[qpart] == signed(jets.size()-2) && (!qqxf_)) weight_=0;
// Ensure qqx in separate jets and adjacent in rapidity
if (indices[qpart] == indices[qpart+1]-1){
outgoing_.at(qpart).type = backquark->type;
outgoing_.at(qpart+1).type = (backquark+1)->type;
}
else weight_=0;
assert(std::is_sorted(begin(outgoing_), end(outgoing_), rapidity_less{}));
}
PhaseSpacePoint::PhaseSpacePoint(
Event const & ev, PhaseSpacePointConfig conf, HEJ::RNG & ran
):
unob_{ev.type() == event_type::unob},
unof_{ev.type() == event_type::unof},
qqxb_{ev.type() == event_type::qqxexb},
qqxf_{ev.type() == event_type::qqxexf},
qqxmid_{ev.type() == event_type::qqxmid},
param_{std::move(conf)},
ran_{ran}
{
weight_ = 1;
const auto Born_jets = sorted_by_rapidity(ev.jets());
const int ng = sample_ng(Born_jets);
weight_ /= std::tgamma(ng + 1);
const int ng_jets = sample_ng_jets(ng, Born_jets);
std::vector<fastjet::PseudoJet> out_partons = gen_non_jet(
ng - ng_jets, CMINPT, param_.jet_param.min_pt
);
const auto qperp = std::accumulate(
begin(out_partons), end(out_partons),
fastjet::PseudoJet{}
);
const auto jets = reshuffle(Born_jets, qperp);
if(weight_ == 0.) return;
if(! pass_resummation_cuts(jets)){
weight_ = 0.;
return;
}
std::vector<fastjet::PseudoJet> jet_partons = split(jets, ng_jets);
if(weight_ == 0.) return;
rescale_rapidities(
out_partons,
most_backward_FKL(jet_partons).rapidity(),
most_forward_FKL(jet_partons).rapidity()
);
if(! cluster_jets(out_partons).empty()){
weight_ = 0.;
return;
}
std::sort(begin(out_partons), end(out_partons), rapidity_less{});
assert(
std::is_sorted(begin(jet_partons), end(jet_partons), rapidity_less{})
);
const auto first_jet_parton = out_partons.insert(
end(out_partons), begin(jet_partons), end(jet_partons)
);
std::inplace_merge(
begin(out_partons), first_jet_parton, end(out_partons), rapidity_less{}
);
if(! jets_ok(Born_jets, out_partons)){
weight_ = 0.;
return;
}
weight_ *= phase_space_normalisation(Born_jets.size(), out_partons.size());
outgoing_.reserve(out_partons.size() + 1); // one slot for possible A, W, Z, H
for(auto & p: out_partons){
- outgoing_.emplace_back(Particle{pid::gluon, std::move(p)});
+ outgoing_.emplace_back(Particle{pid::gluon, std::move(p), {}});
}
const auto WEmit = std::find_if(
begin(ev.outgoing()), end(ev.outgoing()),
[](Particle const & s){ return abs(s.type) == pid::Wp; }
);
if (abs(WEmit->type) == pid::Wp){
outgoing_[unob_].type = filter_partons(ev.outgoing())[unob_].type;
outgoing_.rbegin()[unof_].type = filter_partons(ev.outgoing()).rbegin()[unof_].type;
}
else{
most_backward_FKL(outgoing_).type = ev.incoming().front().type;
most_forward_FKL(outgoing_).type = ev.incoming().back().type;
}
if(qqxmid_||qqxb_||qqxf_){
label_qqx(ev);
}
copy_AWZH_boson_from(ev);
assert(!outgoing_.empty());
reconstruct_incoming(ev.incoming());
}
std::vector<fastjet::PseudoJet> PhaseSpacePoint::gen_non_jet(
int count, double ptmin, double ptmax
){
// heuristic parameters for pt sampling
const double ptpar = 1.3 + count/5.;
const double temp1 = atan((ptmax - ptmin)/ptpar);
std::vector<fastjet::PseudoJet> partons(count);
for(size_t i = 0; i < (size_t) count; ++i){
const double r1 = ran_.get().flat();
const double pt = ptmin + ptpar*tan(r1*temp1);
const double temp2 = cos(r1*temp1);
const double phi = 2*M_PI*ran_.get().flat();
weight_ *= 2.0*M_PI*pt*ptpar*temp1/(temp2*temp2);
// we don't know the allowed rapidity span yet,
// set a random value to be rescaled later on
const double y = ran_.get().flat();
partons[i].reset_PtYPhiM(pt, y, phi);
// Set user index higher than any jet-parton index
// in order to assert that these are not inside jets
partons[i].set_user_index(i + 1 + ng_max);
assert(ptmin-1e-5 <= partons[i].pt() && partons[i].pt() <= ptmax+1e-5);
}
assert(std::all_of(partons.cbegin(), partons.cend(), is_nonjet_parton));
return partons;
}
void PhaseSpacePoint::rescale_rapidities(
std::vector<fastjet::PseudoJet> & partons,
double ymin, double ymax
){
constexpr double ep = 1e-7;
for(auto & parton: partons){
assert(0 <= parton.rapidity() && parton.rapidity() <= 1);
const double dy = ymax - ymin - 2*ep;
const double y = ymin + ep + dy*parton.rapidity();
parton.reset_momentum_PtYPhiM(parton.pt(), y, parton.phi());
weight_ *= dy;
assert(ymin <= parton.rapidity() && parton.rapidity() <= ymax);
}
}
namespace {
template<typename T, typename... Rest>
auto min(T const & a, T const & b, Rest&&... r) {
using std::min;
return min(a, min(b, std::forward<Rest>(r)...));
}
}
double PhaseSpacePoint::probability_in_jet(
std::vector<fastjet::PseudoJet> const & Born_jets
) const{
assert(std::is_sorted(begin(Born_jets), end(Born_jets), rapidity_less{}));
assert(Born_jets.size() >= 2);
const double dy =
Born_jets.back().rapidity() - Born_jets.front().rapidity();
const double R = param_.jet_param.def.R();
const int njets = Born_jets.size();
const double p_J_y_large = (njets-1)*R*R/(2.*dy);
const double p_J_y0 = njets*R/M_PI;
return min(p_J_y_large, p_J_y0, 1.);
}
int PhaseSpacePoint::sample_ng_jets(
int ng, std::vector<fastjet::PseudoJet> const & Born_jets
){
const double p_J = probability_in_jet(Born_jets);
std::binomial_distribution<> bin_dist(ng, p_J);
const int ng_J = bin_dist(ran_.get());
weight_ *= std::pow(p_J, -ng_J)*std::pow(1 - p_J, ng_J - ng);
return ng_J;
}
std::vector<fastjet::PseudoJet> PhaseSpacePoint::reshuffle(
std::vector<fastjet::PseudoJet> const & Born_jets,
fastjet::PseudoJet const & q
){
if(q == fastjet::PseudoJet{0, 0, 0, 0}) return Born_jets;
const auto jets = resummation_jet_momenta(Born_jets, q);
if(jets.empty()){
weight_ = 0;
return {};
}
// additional Jacobian to ensure Born integration over delta gives 1
weight_ *= resummation_jet_weight(Born_jets, q);
return jets;
}
std::vector<int> PhaseSpacePoint::distribute_jet_partons(
int ng_jets, std::vector<fastjet::PseudoJet> const & jets
){
size_t first_valid_jet = 0;
size_t num_valid_jets = jets.size();
const double R_eff = 5./3.*param_.jet_param.def.R();
// if there is an unordered jet too far away from the FKL jets
// then extra gluon constituents of the unordered jet would
// violate the FKL rapidity ordering
if((unob_||qqxb_) && jets[0].delta_R(jets[1]) > R_eff){
++first_valid_jet;
--num_valid_jets;
}
else if((unof_||qqxf_) && jets[jets.size()-1].delta_R(jets[jets.size()-2]) > R_eff){
--num_valid_jets;
}
std::vector<int> np(jets.size(), 1);
for(int i = 0; i < ng_jets; ++i){
++np[first_valid_jet + ran_.get().flat() * num_valid_jets];
}
weight_ *= std::pow(num_valid_jets, ng_jets);
return np;
}
#ifndef NDEBUG
namespace{
bool tagged_FKL_backward(
std::vector<fastjet::PseudoJet> const & jet_partons
){
return std::find_if(
begin(jet_partons), end(jet_partons),
[](fastjet::PseudoJet const & p){
return p.user_index() == backward_FKL_idx;
}
) != end(jet_partons);
}
bool tagged_FKL_forward(
std::vector<fastjet::PseudoJet> const & jet_partons
){
// the most forward FKL parton is most likely near the end of jet_partons;
// start search from there
return std::find_if(
jet_partons.rbegin(), jet_partons.rend(),
[](fastjet::PseudoJet const & p){
return p.user_index() == forward_FKL_idx;
}
) != jet_partons.rend();
}
bool tagged_FKL_extremal(
std::vector<fastjet::PseudoJet> const & jet_partons
){
return tagged_FKL_backward(jet_partons) && tagged_FKL_forward(jet_partons);
}
} // namespace anonymous
#endif
std::vector<fastjet::PseudoJet> PhaseSpacePoint::split(
std::vector<fastjet::PseudoJet> const & jets,
int ng_jets
){
return split(jets, distribute_jet_partons(ng_jets, jets));
}
bool PhaseSpacePoint::pass_extremal_cuts(
fastjet::PseudoJet const & ext_parton,
fastjet::PseudoJet const & jet
) const{
if(ext_parton.pt() < param_.min_extparton_pt) return false;
return (ext_parton - jet).pt()/jet.pt() < param_.max_ext_soft_pt_fraction;
}
std::vector<fastjet::PseudoJet> PhaseSpacePoint::split(
std::vector<fastjet::PseudoJet> const & jets,
std::vector<int> const & np
){
assert(! jets.empty());
assert(jets.size() == np.size());
assert(pass_resummation_cuts(jets));
const size_t most_backward_FKL_idx = 0 + unob_ + qqxb_;
const size_t most_forward_FKL_idx = jets.size() - 1 - unof_ - qqxf_;
const auto & jet = param_.jet_param;
const JetSplitter jet_splitter{jet.def, jet.min_pt, ran_};
std::vector<fastjet::PseudoJet> jet_partons;
// randomly distribute jet gluons among jets
for(size_t i = 0; i < jets.size(); ++i){
auto split_res = jet_splitter.split(jets[i], np[i]);
weight_ *= split_res.weight;
if(weight_ == 0) return {};
assert(
std::all_of(
begin(split_res.constituents), end(split_res.constituents),
is_jet_parton
)
);
const auto first_new_parton = jet_partons.insert(
end(jet_partons),
begin(split_res.constituents), end(split_res.constituents)
);
// mark uno and extremal FKL emissions here so we can check
// their position once all emissions are generated
auto extremal = end(jet_partons);
if (i == most_backward_FKL_idx){ //FKL backward emission
extremal = std::min_element(
first_new_parton, end(jet_partons), rapidity_less{}
);
extremal->set_user_index(backward_FKL_idx);
}
else if(((unob_ || qqxb_) && i == 0)){
// unordered/qqxb
extremal = std::min_element(
first_new_parton, end(jet_partons), rapidity_less{}
);
extremal->set_user_index((unob_)?unob_idx:qqxb_idx);
}
else if (i == most_forward_FKL_idx){
extremal = std::max_element(
first_new_parton, end(jet_partons), rapidity_less{}
);
extremal->set_user_index(forward_FKL_idx);
}
else if(((unof_ || qqxf_) && i == jets.size() - 1)){
// unordered/qqxf
extremal = std::max_element(
first_new_parton, end(jet_partons), rapidity_less{}
);
extremal->set_user_index((unof_)?unof_idx:qqxf_idx);
}
if(
extremal != end(jet_partons)
&& !pass_extremal_cuts(*extremal, jets[i])
){
weight_ = 0;
return {};
}
}
assert(tagged_FKL_extremal(jet_partons));
std::sort(begin(jet_partons), end(jet_partons), rapidity_less{});
if(
!extremal_ok(jet_partons)
|| !split_preserved_jets(jets, jet_partons)
){
weight_ = 0.;
return {};
}
return jet_partons;
}
bool PhaseSpacePoint::extremal_ok(
std::vector<fastjet::PseudoJet> const & partons
) const{
assert(std::is_sorted(begin(partons), end(partons), rapidity_less{}));
if(unob_ && partons.front().user_index() != unob_idx) return false;
if(unof_ && partons.back().user_index() != unof_idx) return false;
if(qqxb_ && partons.front().user_index() != qqxb_idx) return false;
if(qqxf_ && partons.back().user_index() != qqxf_idx) return false;
return
most_backward_FKL(partons).user_index() == backward_FKL_idx
&& most_forward_FKL(partons).user_index() == forward_FKL_idx;
}
bool PhaseSpacePoint::split_preserved_jets(
std::vector<fastjet::PseudoJet> const & jets,
std::vector<fastjet::PseudoJet> const & jet_partons
) const{
assert(std::is_sorted(begin(jets), end(jets), rapidity_less{}));
const auto split_jets = sorted_by_rapidity(cluster_jets(jet_partons));
// this can happen if two overlapping jets
// are both split into more than one parton
if(split_jets.size() != jets.size()) return false;
for(size_t i = 0; i < split_jets.size(); ++i){
// this can happen if there are two overlapping jets
// and a parton is assigned to the "wrong" jet
if(!nearby_ep(jets[i].rapidity(), split_jets[i].rapidity(), 1e-2)){
return false;
}
}
return true;
}
template<class Particle>
Particle const & PhaseSpacePoint::most_backward_FKL(
std::vector<Particle> const & partons
) const{
return partons[0 + unob_ + qqxb_];
}
template<class Particle>
Particle const & PhaseSpacePoint::most_forward_FKL(
std::vector<Particle> const & partons
) const{
const size_t idx = partons.size() - 1 - unof_ - qqxf_;
assert(idx < partons.size());
return partons[idx];
}
template<class Particle>
Particle & PhaseSpacePoint::most_backward_FKL(
std::vector<Particle> & partons
) const{
return partons[0 + unob_ + qqxb_];
}
template<class Particle>
Particle & PhaseSpacePoint::most_forward_FKL(
std::vector<Particle> & partons
) const{
const size_t idx = partons.size() - 1 - unof_ - qqxf_;
assert(idx < partons.size());
return partons[idx];
}
namespace {
bool contains_idx(
fastjet::PseudoJet const & jet, fastjet::PseudoJet const & parton
){
auto const & constituents = jet.constituents();
const int idx = parton.user_index();
return std::find_if(
begin(constituents), end(constituents),
[idx](fastjet::PseudoJet const & con){return con.user_index() == idx;}
) != end(constituents);
}
}
/**
* final jet test:
* - number of jets must match Born kinematics
* - no partons designated as nonjet may end up inside jets
* - all other outgoing partons *must* end up inside jets
* - the extremal (in rapidity) partons must be inside the extremal jets
* - rapidities must be the same (by construction)
*/
bool PhaseSpacePoint::jets_ok(
std::vector<fastjet::PseudoJet> const & Born_jets,
std::vector<fastjet::PseudoJet> const & partons
) const{
fastjet::ClusterSequence cs(partons, param_.jet_param.def);
const auto jets = sorted_by_rapidity(cs.inclusive_jets(param_.jet_param.min_pt));
if(jets.size() != Born_jets.size()) return false;
int in_jet = 0;
for(size_t i = 0; i < jets.size(); ++i){
assert(jets[i].has_constituents());
for(auto && parton: jets[i].constituents()){
if(is_nonjet_parton(parton)) return false;
}
in_jet += jets[i].constituents().size();
}
const int expect_in_jet = std::count_if(
partons.cbegin(), partons.cend(), is_jet_parton
);
if(in_jet != expect_in_jet) return false;
// note that PseudoJet::contains does not work here
if(! (
contains_idx(most_backward_FKL(jets), most_backward_FKL(partons))
&& contains_idx(most_forward_FKL(jets), most_forward_FKL(partons))
)) return false;
if(unob_ && !contains_idx(jets.front(), partons.front())) return false;
if(unof_ && !contains_idx(jets.back(), partons.back())) return false;
for(size_t i = 0; i < jets.size(); ++i){
assert(nearby_ep(jets[i].rapidity(), Born_jets[i].rapidity(), 1e-2));
}
return true;
}
void PhaseSpacePoint::reconstruct_incoming(
std::array<Particle, 2> const & Born_incoming
){
std::tie(incoming_[0].p, incoming_[1].p) = incoming_momenta(outgoing_);
for(size_t i = 0; i < incoming_.size(); ++i){
incoming_[i].type = Born_incoming[i].type;
}
assert(momentum_conserved());
}
double PhaseSpacePoint::phase_space_normalisation(
int num_Born_jets, int num_out_partons
) const{
return pow(16*pow(M_PI,3), num_Born_jets - num_out_partons);
}
bool PhaseSpacePoint::momentum_conserved() const{
fastjet::PseudoJet diff;
for(auto const & in: incoming()) diff += in.p;
const double norm = diff.E();
for(auto const & out: outgoing()) diff -= out.p;
return nearby(diff, fastjet::PseudoJet{}, norm);
}
} //namespace HEJ
diff --git a/src/Weights.cc b/src/Weights.cc
deleted file mode 100644
index de2d561..0000000
--- a/src/Weights.cc
+++ /dev/null
@@ -1,46 +0,0 @@
-/**
- * \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
- * \date 2019
- * \copyright GPLv2 or later
- */
-#include "HEJ/Weights.hh"
-
-#include <stdexcept>
-
-namespace HEJ {
-
- Weights& Weights::operator*=(Weights const & other) {
- if(other.variations.size() != variations.size()) {
- throw std::invalid_argument{"Wrong number of weights"};
- }
- central *= other.central;
- for(std::size_t i = 0; i < variations.size(); ++i) {
- variations[i] *= other.variations[i];
- }
- return *this;
- }
-
- Weights& Weights::operator*=(double factor) {
- central *= factor;
- for(auto & wt: variations) wt *= factor;
- return *this;
- }
-
- Weights& Weights::operator/=(Weights const & other) {
- if(other.variations.size() != variations.size()) {
- throw std::invalid_argument{"Wrong number of weights"};
- }
- central /= other.central;
- for(std::size_t i = 0; i < variations.size(); ++i) {
- variations[i] /= other.variations[i];
- }
- return *this;
- }
-
- Weights& Weights::operator/=(double factor) {
- central /= factor;
- for(auto & wt: variations) wt /= factor;
- return *this;
- }
-
-}
diff --git a/src/bin/HEJ.cc b/src/bin/HEJ.cc
index 6793c30..77d6f1e 100644
--- a/src/bin/HEJ.cc
+++ b/src/bin/HEJ.cc
@@ -1,188 +1,189 @@
/**
* \authors Jeppe Andersen, Tuomas Hapola, Marian Heil, Andreas Maier, Jennifer Smillie
* \date 2019
* \copyright GPLv2 or later
*/
#include <array>
#include <chrono>
#include <iostream>
#include <limits>
#include <memory>
#include <numeric>
#include "yaml-cpp/yaml.h"
#include "LHEF/LHEF.h"
#include "fastjet/ClusterSequence.hh"
#include "HEJ/CombinedEventWriter.hh"
#include "HEJ/config.hh"
#include "HEJ/CrossSectionAccumulator.hh"
#include "HEJ/Event.hh"
#include "HEJ/EventReweighter.hh"
#include "HEJ/get_analysis.hh"
#include "HEJ/make_RNG.hh"
#include "HEJ/ProgressBar.hh"
#include "HEJ/stream.hh"
#include "HEJ/Version.hh"
#include "HEJ/YAMLreader.hh"
int event_number(std::string const & record){
size_t start = record.rfind("Number of Events");
start = record.find_first_of("123456789", start);
if(start == std::string::npos) {
throw std::invalid_argument("no event number record found");
}
const size_t end = record.find_first_not_of("0123456789", start);
return std::stoi(record.substr(start, end - start));
}
HEJ::Config load_config(char const * filename){
try{
return HEJ::load_config(filename);
}
catch(std::exception const & exc){
std::cerr << "Error: " << exc.what() << '\n';
std::exit(EXIT_FAILURE);
}
}
std::unique_ptr<HEJ::Analysis> get_analysis(
YAML::Node const & parameters
){
try{
return HEJ::get_analysis(parameters);
}
catch(std::exception const & exc){
std::cerr << "Failed to load analysis: " << exc.what() << '\n';
std::exit(EXIT_FAILURE);
}
}
// unique_ptr is a workaround:
// HEJ::optional is a better fit, but gives spurious errors with g++ 7.3.0
std::unique_ptr<HEJ::ProgressBar<double>> make_progress_bar(
std::vector<double> const & xs
) {
if(xs.empty()) return {};
const double Born_xs = std::accumulate(begin(xs), end(xs), 0.);
return std::make_unique<HEJ::ProgressBar<double>>(std::cout, Born_xs);
}
std::string time_to_string(const time_t time){
char s[30];
struct tm * p = localtime(&time);
strftime(s, 30, "%a %b %d %Y %H:%M:%S", p);
return s;
}
int main(int argn, char** argv) {
using clock = std::chrono::system_clock;
if (argn < 3) {
std::cerr << "\n# Usage:\n."<< argv[0] <<" config_file input_file\n\n";
return EXIT_FAILURE;
}
const auto start_time = clock::now();
{
std::cout << "Starting " << HEJ::Version::package_name_full()
<< ", revision " << HEJ::Version::revision() << " ("
<< time_to_string(clock::to_time_t(start_time)) << ")" << std::endl;
}
fastjet::ClusterSequence::print_banner();
// read configuration
const HEJ::Config config = load_config(argv[1]);
HEJ::istream in{argv[2]};
std::unique_ptr<HEJ::Analysis> analysis = get_analysis(
config.analysis_parameters
);
assert(analysis != nullptr);
LHEF::Reader reader{in};
auto heprup = reader.heprup;
heprup.generators.emplace_back(LHEF::XMLTag{});
heprup.generators.back().name = HEJ::Version::package_name();
heprup.generators.back().version = HEJ::Version::String();
HEJ::CombinedEventWriter writer{config.output, std::move(heprup)};
double global_reweight = 1.;
int max_events = std::numeric_limits<int>::max();
if(argn > 3){
max_events = std::stoi(argv[3]);
const int input_events = event_number(reader.headerBlock);
global_reweight = input_events/static_cast<double>(max_events);
std::cout << "Processing " << max_events
<< " out of " << input_events << " events\n";
}
HEJ::ScaleGenerator scale_gen{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
};
auto ran = HEJ::make_RNG(config.rng.name, config.rng.seed);
assert(ran != nullptr);
HEJ::EventReweighter hej{
reader.heprup,
std::move(scale_gen),
to_EventReweighterConfig(config),
*ran
};
int nevent = 0;
std::array<int, HEJ::event_type::last_type + 1>
nevent_type{0}, nfailed_type{0};
auto progress = make_progress_bar(reader.heprup.XSECUP);
HEJ::CrossSectionAccumulator xs;
// Loop over the events in the inputfile
while(reader.readEvent()){
// reweight events so that the total cross section is conserved
reader.hepeup.setWeight(0, global_reweight * reader.hepeup.weight());
if(nevent == max_events) break;
++nevent;
// calculate HEJ weight
HEJ::Event FO_event{
- HEJ::UnclusteredEvent{reader.hepeup},
- config.fixed_order_jets.def, config.fixed_order_jets.min_pt,
+ HEJ::Event::EventData{reader.hepeup}(
+ config.fixed_order_jets.def, config.fixed_order_jets.min_pt
+ )
};
auto resummed_events = hej.reweight(FO_event, config.trials);
++nevent_type[FO_event.type()];
if(resummed_events.empty()) ++nfailed_type[FO_event.type()];
for(auto const & ev: resummed_events){
//TODO: move pass_cuts to after phase space point generation
if(analysis->pass_cuts(ev, FO_event)){
analysis->fill(ev, FO_event);
writer.write(ev);
xs.fill(ev);
}
}
if(progress) progress->increment(FO_event.central().weight);
} // main event loop
std::cout << '\n';
analysis->finalise();
using namespace HEJ::event_type;
std::cout<< "Events processed: " << nevent << '\n';
for(size_t ev_type = first_type; ev_type <= last_type; ++ev_type){
std::cout << '\t' << names[ev_type] << ": " << nevent_type[ev_type]
<< ", failed to reconstruct " << nfailed_type[ev_type]
<< '\n';
}
std::cout << '\n' << xs << '\n';
std::chrono::duration<double> run_time = (clock::now() - start_time);
std::cout << "Finished " << HEJ::Version::package_name() << " at "
<< time_to_string(clock::to_time_t(clock::now()))
<< "\n=> Runtime: " << run_time.count() << " sec ("
<< nevent/run_time.count() << " Events/sec).\n";
}
diff --git a/t/check_res.cc b/t/check_res.cc
index 294a8d1..88fdd47 100644
--- a/t/check_res.cc
+++ b/t/check_res.cc
@@ -1,101 +1,134 @@
#include <iostream>
#include "LHEF/LHEF.h"
#include "HEJ/Event.hh"
#include "HEJ/EventReweighter.hh"
#include "HEJ/Mixmax.hh"
#include "HEJ/stream.hh"
+#define ASSERT(x) if(!(x)) { \
+ std::cerr << "Assertion '" #x "' failed.\n"; \
+ return EXIT_FAILURE; \
+ }
+
namespace{
const fastjet::JetDefinition jet_def{fastjet::kt_algorithm, 0.4};
const fastjet::JetDefinition Born_jet_def{jet_def};
constexpr double Born_jetptmin = 30;
constexpr double extpartonptmin = 30;
constexpr double max_ext_soft_pt_fraction =
std::numeric_limits<double>::infinity();
constexpr double jetptmin = 35;
constexpr bool log_corr = false;
using EventTreatment = HEJ::EventTreatment;
using namespace HEJ::event_type;
HEJ::EventTreatMap treat{
{no_2_jets, EventTreatment::discard},
{bad_final_state, EventTreatment::discard},
{nonHEJ, EventTreatment::discard},
{unof, EventTreatment::discard},
{unob, EventTreatment::discard},
{qqxexb, EventTreatment::discard},
{qqxexf, EventTreatment::discard},
{qqxmid, EventTreatment::discard},
{FKL, EventTreatment::reweight}
};
+
+ /// true if colour is allowed for particle
+ bool correct_colour(HEJ::Particle const & part){
+ if(HEJ::is_AWZH_boson(part) && !part.colour) return true;
+ if(!part.colour) return false;
+ int const colour = part.colour->first;
+ int const anti_colour = part.colour->second;
+ if(part.type == HEJ::ParticleID::gluon)
+ return colour != anti_colour && colour > 0 && anti_colour > 0;
+ if(HEJ::is_quark(part))
+ return anti_colour == 0 && colour > 0;
+ return colour == 0 && anti_colour > 0;
+ }
+ bool correct_colour(HEJ::Event const & ev){
+ if(!HEJ::event_type::is_HEJ(ev.type()))
+ return true;
+ for(auto const & part: ev.incoming()){
+ if(!correct_colour(part))
+ return false;
+ }
+ for(auto const & part: ev.outgoing()){
+ if(!correct_colour(part))
+ return false;
+ }
+ return true;
+ }
};
int main(int argn, char** argv) {
if(argn == 5 && std::string(argv[4]) == "uno"){
--argn;
treat[unof] = EventTreatment::reweight;
treat[unob] = EventTreatment::reweight;
treat[FKL] = EventTreatment::discard;
}
if(argn != 4){
std::cerr << "Usage: check_res eventfile xsection tolerance [uno]";
return EXIT_FAILURE;
}
const double xsec_ref = std::stod(argv[2]);
const double tolerance = std::stod(argv[3]);
HEJ::istream in{argv[1]};
LHEF::Reader reader{in};
HEJ::PhaseSpacePointConfig psp_conf;
psp_conf.jet_param = HEJ::JetParameters{jet_def, jetptmin};
psp_conf.min_extparton_pt = extpartonptmin;
psp_conf.max_ext_soft_pt_fraction = max_ext_soft_pt_fraction;
HEJ::MatrixElementConfig ME_conf;
ME_conf.log_correction = log_corr;
ME_conf.Higgs_coupling = HEJ::HiggsCouplingSettings{};
HEJ::EventReweighterConfig conf;
conf.psp_config = std::move(psp_conf);
conf.ME_config = std::move(ME_conf);
conf.jet_param = psp_conf.jet_param;
conf.treat = treat;
reader.readEvent();
const bool has_Higgs = std::find(
begin(reader.hepeup.IDUP),
end(reader.hepeup.IDUP),
25
) != end(reader.hepeup.IDUP);
const double mu = has_Higgs?125.:91.188;
HEJ::ScaleGenerator scale_gen{
{{std::to_string(mu), HEJ::FixedScale{mu}}}, {}, 1.
};
HEJ::Mixmax ran{};
HEJ::EventReweighter hej{reader.heprup, std::move(scale_gen), conf, ran};
double xsec = 0.;
double xsec_err = 0.;
do{
HEJ::Event ev{
- HEJ::UnclusteredEvent{reader.hepeup},
- Born_jet_def, Born_jetptmin
+ HEJ::Event::EventData{reader.hepeup}.cluster(
+ Born_jet_def, Born_jetptmin
+ )
};
auto resummed_events = hej.reweight(ev, 20);
for(auto const & ev: resummed_events) {
+ ASSERT(correct_colour(ev));
xsec += ev.central().weight;
xsec_err += ev.central().weight*ev.central().weight;
}
} while(reader.readEvent());
xsec_err = std::sqrt(xsec_err);
const double significance =
std::abs(xsec - xsec_ref) / std::sqrt( xsec_err*xsec_err + tolerance*tolerance );
std::cout << xsec_ref << " +/- " << tolerance << " ~ "
<< xsec << " +- " << xsec_err << " => " << significance << " sigma\n";
if(significance > 3.){
std::cerr << "Cross section is off by over 3 sigma!\n";
return EXIT_FAILURE;
}
}
diff --git a/t/test_ME_generic.cc b/t/test_ME_generic.cc
index 8430431..7ad3f45 100644
--- a/t/test_ME_generic.cc
+++ b/t/test_ME_generic.cc
@@ -1,116 +1,132 @@
// Generic tester for the ME for a given set of PSP
// reference weights and PSP (as LHE file) have to be given as _individual_ files
#include <fstream>
+#include <random>
+#include <algorithm>
#include "LHEF/LHEF.h"
#include "HEJ/MatrixElement.hh"
#include "HEJ/Event.hh"
#include "HEJ/YAMLreader.hh"
#include "HEJ/stream.hh"
constexpr double alpha_s = 0.118;
constexpr double ep = 1e-5;
+void shuffle_particles(HEJ::Event::EventData & ev) {
+ static std::mt19937_64 ran{0};
+ std::shuffle(begin(ev.incoming), end(ev.incoming), ran);
+ std::shuffle(begin(ev.outgoing), end(ev.outgoing), ran);
+}
+
void dump(HEJ::Event const & ev){
{
LHEF::Writer writer{std::cout};
std::cout << std::setprecision(6);
writer.hepeup = to_HEPEUP(std::move(ev), nullptr);
writer.writeEvent();
}
std::cout << "Rapidity ordering:\n";
for(const auto & part: ev.outgoing()){
std::cout << std::setw(2) << part.type << ": "<< std::setw(7) << part.rapidity() << std::endl;
}
}
enum MEComponent {tree, virt};
MEComponent guess_component(std::string const & data_file) {
if(data_file.find("virt") != data_file.npos) return MEComponent::virt;
return MEComponent::tree;
}
int main(int argn, char** argv){
if(argn != 4 && argn != 5){
std::cerr << "\n# Usage:\n."<< argv[0] <<" config.yml ME_weights input_file.lhe\n\n";
return EXIT_FAILURE;
}
bool OUTPUT_MODE = false;
if(argn == 5 && std::string("OUTPUT")==std::string(argv[4]))
OUTPUT_MODE = true;
const HEJ::Config config = HEJ::load_config(argv[1]);
std::fstream wgt_file;
if ( OUTPUT_MODE ) {
std::cout << "_______________________USING OUTPUT MODE!_______________________" << std::endl;
wgt_file.open(argv[2], std::fstream::out);
wgt_file.precision(10);
} else {
wgt_file.open(argv[2], std::fstream::in);
}
HEJ::istream in{argv[3]};
LHEF::Reader reader{in};
const auto component = guess_component(argv[2]);
HEJ::MatrixElement ME{
[](double){ return alpha_s; },
HEJ::to_MatrixElementConfig(config)
};
double max_ratio = 0.;
size_t idx_max_ratio = 0;
- HEJ::Event ev_max_ratio;
+
+ HEJ::Event ev_max_ratio(HEJ::Event::EventData{}.cluster(
+ config.resummation_jets.def,0
+ )
+ );
double av_ratio = 0;
size_t i = 0;
while(reader.readEvent()){
++i;
+ HEJ::Event::EventData data{reader.hepeup};
+ shuffle_particles(data);
+
HEJ::Event event{
- HEJ::UnclusteredEvent{reader.hepeup},
- config.resummation_jets.def,
- config.resummation_jets.min_pt
+ data.cluster(
+ config.resummation_jets.def,
+ config.resummation_jets.min_pt
+ )
};
const double our_ME = (component == MEComponent::tree)?
ME.tree(event).central:
ME.virtual_corrections(event).central
;
if ( OUTPUT_MODE ) {
wgt_file << our_ME << std::endl;
} else {
std::string line;
if(!std::getline(wgt_file,line)) break;
const double ref_ME = std::stod(line);
const double diff = std::abs(our_ME/ref_ME-1.);
av_ratio+=diff;
if( diff > max_ratio ) {
max_ratio = diff;
idx_max_ratio = i;
ev_max_ratio = event;
}
if( diff > ep ){
size_t precision(std::cout.precision());
std::cout.precision(16);
std::cout<< "Large difference in PSP " << i << "\nis: "<<our_ME << " should: " << ref_ME << " => difference: " << diff << std::endl;
std::cout.precision(precision);
dump(event);
return EXIT_FAILURE;
}
}
}
wgt_file.close();
if ( !OUTPUT_MODE ) {
size_t precision(std::cout.precision());
std::cout.precision(16);
std::cout << "Avg ratio after " << i << " PSP: " << av_ratio/i << std::endl;
std::cout << "maximal ratio at " << idx_max_ratio << ": " << max_ratio << std::endl;
std::cout.precision(precision);
}
return EXIT_SUCCESS;
}
diff --git a/t/test_classify.cc b/t/test_classify.cc
index c7c93d8..13081e3 100644
--- a/t/test_classify.cc
+++ b/t/test_classify.cc
@@ -1,50 +1,62 @@
+#include <random>
+#include <algorithm>
+
#include "LHEF/LHEF.h"
#include "HEJ/stream.hh"
#include "HEJ/event_types.hh"
#include "HEJ/Event.hh"
namespace{
constexpr double min_jet_pt = 30.;
const fastjet::JetDefinition jet_def{fastjet::kt_algorithm, 0.4};
using namespace HEJ::event_type;
static const std::vector<EventType> results{
unob,FKL,FKL,FKL,FKL,FKL,FKL,unob,FKL,unob,FKL,FKL,FKL,unof,FKL,unob,FKL,
FKL,unob,unob,FKL,FKL,unob,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,unof,
FKL,FKL,unof,FKL,FKL,FKL,FKL,FKL,unof,FKL,FKL,FKL,unof,FKL,FKL,unob,unof,
FKL,unof,FKL,unob,FKL,FKL,unob,FKL,unob,unof,unob,unof,FKL,FKL,FKL,FKL,FKL,
FKL,FKL,FKL,FKL,FKL,FKL,FKL,unob,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,unob,FKL,
FKL,FKL,FKL,unof,FKL,unob,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,unob,FKL,
FKL,FKL,FKL,FKL,unob,FKL,unob,unob,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,FKL,unof,unob,FKL
};
+
+ void shuffle_particles(HEJ::Event::EventData & ev) {
+ static std::mt19937_64 ran{0};
+ std::shuffle(begin(ev.incoming), end(ev.incoming), ran);
+ std::shuffle(begin(ev.outgoing), end(ev.outgoing), ran);
+ }
}
int main(int argn, char** argv) {
if(argn != 2){
std::cerr << "Usage: test_classify eventfile";
return EXIT_FAILURE;
}
HEJ::istream in{argv[1]};
LHEF::Reader reader{in};
LHEF::Writer writer{std::cerr};
writer.heprup = reader.heprup;
for(auto const & expected: results){
reader.readEvent();
+ HEJ::Event::EventData data{reader.hepeup};
+ shuffle_particles(data);
const HEJ::Event ev{
- HEJ::UnclusteredEvent{reader.hepeup},
+ data.cluster(
jet_def, min_jet_pt
+ )
};
if(ev.type() != expected){
using HEJ::event_type::names;
writer.hepeup = reader.hepeup;
std::cerr << "wrong classification of event:\n";
writer.writeEvent();
std::cerr << "classified as " << names[ev.type()]
<< ", is " << names[expected] << '\n';
return EXIT_FAILURE;
}
}
}
diff --git a/t/test_colours.cc b/t/test_colours.cc
new file mode 100644
index 0000000..d2c29e6
--- /dev/null
+++ b/t/test_colours.cc
@@ -0,0 +1,221 @@
+#include <random>
+#include <stdexcept>
+#include <utility>
+
+#include "HEJ/Event.hh"
+#include "HEJ/RNG.hh"
+
+#define ASSERT(x) if(!(x)) { \
+ throw std::logic_error("Assertion '" #x "' failed."); \
+ }
+
+/// biased RNG to connect always to colour
+class dum_rnd: public HEJ::DefaultRNG {
+public:
+ dum_rnd() = default;
+ double flat() override {
+ return 0.;
+ };
+};
+
+void shuffle_particles(HEJ::Event::EventData & ev) {
+ static std::mt19937_64 ran{0};
+ std::shuffle(begin(ev.incoming), end(ev.incoming), ran);
+ std::shuffle(begin(ev.outgoing), end(ev.outgoing), ran);
+}
+
+void dump_event(HEJ::Event const & ev){
+ for(auto const & in: ev.incoming()){
+ std::cerr << "in type=" << in.type
+ << ", colour={" << (*in.colour).first
+ << ", " << (*in.colour).second << "}\n";
+ }
+ for(auto const & out: ev.outgoing()){
+ std::cerr << "out type=" << out.type << ", colour={";
+ if(out.colour)
+ std::cerr << (*out.colour).first << ", " << (*out.colour).second;
+ else
+ std::cerr << "non, non";
+ std::cerr << "}\n";
+ }
+}
+
+/// true if colour is allowed for particle
+bool correct_colour(HEJ::Particle const & part){
+ if(HEJ::is_AWZH_boson(part) && !part.colour) return true;
+ if(!part.colour) return false;
+ int const colour = part.colour->first;
+ int const anti_colour = part.colour->second;
+ if(part.type == HEJ::ParticleID::gluon)
+ return colour != anti_colour && colour > 0 && anti_colour > 0;
+ if(HEJ::is_quark(part))
+ return anti_colour == 0 && colour > 0;
+ return colour == 0 && anti_colour > 0;
+}
+
+bool correct_colour(HEJ::Event const & ev){
+ for(auto const & part: ev.incoming()){
+ if(!correct_colour(part))
+ return false;
+ }
+ for(auto const & part: ev.outgoing()){
+ if(!correct_colour(part))
+ return false;
+ }
+ return true;
+}
+
+bool match_expected(
+ HEJ::Event const & ev,
+ std::vector<HEJ::Colour> const & expected
+){
+ ASSERT(ev.outgoing().size()+2==expected.size());
+ for(size_t i=0; i<ev.incoming().size(); ++i){
+ ASSERT(ev.incoming()[i].colour);
+ if( *ev.incoming()[i].colour != expected[i])
+ return false;
+ }
+ for(size_t i=2; i<ev.outgoing().size()+2; ++i){
+ if( ev.outgoing()[i-2].colour ){
+ if( *ev.outgoing()[i-2].colour != expected[i] )
+ return false;
+ } else if( expected[i].first != 0 || expected[i].second != 0)
+ return false;
+ }
+ return true;
+}
+
+void check_event(
+ HEJ::Event::EventData unc_ev, std::vector<HEJ::Colour> const & expected_colours
+){
+ shuffle_particles(unc_ev); // make sure incoming order doesn't matter
+ HEJ::Event ev{unc_ev.cluster(
+ fastjet::JetDefinition(fastjet::JetAlgorithm::antikt_algorithm, 0.4), 30.)
+ };
+ ASSERT(HEJ::event_type::is_HEJ(ev.type()));
+ dum_rnd rng;
+ ASSERT(ev.generate_colours(rng));
+ if(!correct_colour(ev)){
+ std::cerr << "Found illegal colours for event\n";
+ dump_event(ev);
+ throw std::invalid_argument("Illegal colour set");
+ }
+ if(!match_expected(ev, expected_colours)){
+ std::cerr << "Colours didn't match expectation. Found\n";
+ dump_event(ev);
+ std::cerr << "but expected\n";
+ for(auto const & col: expected_colours){
+ std::cerr << "colour={" << col.first << ", " << col.second << "}\n";
+ }
+ throw std::logic_error("Colours did not match expectation");
+ }
+}
+
+int main() {
+ HEJ::Event::EventData ev;
+ std::vector<HEJ::Colour> expected_colours(7);
+
+ /// pure gluon
+ ev.incoming[0] = { HEJ::ParticleID::gluon, { 0, 0,-427, 427}, {}};
+ ev.incoming[1] = { HEJ::ParticleID::gluon, { 0, 0, 851, 851}, {}};
+ ev.outgoing.push_back({ HEJ::ParticleID::gluon, { 196, 124, -82, 246}, {}});
+ ev.outgoing.push_back({ HEJ::ParticleID::gluon, {-167,-184, 16, 249}, {}});
+ ev.outgoing.push_back({ HEJ::ParticleID::higgs, { 197, 180, 168, 339}, {}});
+ ev.outgoing.push_back({ HEJ::ParticleID::gluon, {-190, -57, 126, 235}, {}});
+ ev.outgoing.push_back({ HEJ::ParticleID::gluon, { -36, -63, 196, 209}, {}});
+
+ expected_colours[0] = {502, 501};
+ expected_colours[1] = {509, 502};
+ expected_colours[2] = {503, 501};
+ expected_colours[3] = {505, 503};
+ expected_colours[4] = { 0, 0};
+ expected_colours[5] = {507, 505};
+ expected_colours[6] = {509, 507};
+ check_event(ev, expected_colours);
+
+ /// last g to Qx (=> gQx -> g ... Qx)
+ ev.incoming[1].type = HEJ::ParticleID::d_bar;
+ ev.outgoing[4].type = HEJ::ParticleID::d_bar;
+ // => only end changes
+ expected_colours[1].first = 0;
+ expected_colours[6].first = 0;
+ check_event(ev, expected_colours);
+
+ {
+ // don't overwrite
+ auto new_expected = expected_colours;
+ auto new_ev = ev;
+ /// uno forward (=> gQx -> g ... Qx g)
+ std::swap(new_ev.outgoing[3].type, new_ev.outgoing[4].type);
+ // => uno quarks eats colour and gluon connects to anti-colour
+ new_expected[5] = {0, expected_colours[3].first};
+ new_expected[6] = {expected_colours[0].first, expected_colours[0].first+2};
+ new_expected[1].second += 2; // one more anti-colour in line
+ check_event(new_ev, new_expected);
+ }
+
+ /// swap Qx <-> Q (=> gQ -> g ... Q)
+ ev.incoming[1].type = HEJ::ParticleID::d;
+ ev.outgoing[4].type = HEJ::ParticleID::d;
+ // => swap: colour<->anti && inital<->final
+ std::swap(expected_colours[1], expected_colours[6]);
+ std::swap(expected_colours[1].first, expected_colours[1].second);
+ std::swap(expected_colours[6].first, expected_colours[6].second);
+ check_event(ev, expected_colours);
+
+ /// first g to qx (=> qxQ -> qx ... Q)
+ ev.incoming[0].type = HEJ::ParticleID::u_bar;
+ ev.outgoing[0].type = HEJ::ParticleID::u_bar;
+ expected_colours[0] = { 0, 501};
+ // => shift anti-colour index one up
+ expected_colours[1].first -= 2;
+ expected_colours[5] = expected_colours[3];
+ expected_colours[3] = expected_colours[2];
+ expected_colours[2] = { 0, 502};
+ check_event(ev, expected_colours);
+
+ {
+ // don't overwrite
+ auto new_expected = expected_colours;
+ auto new_ev = ev;
+ /// uno backward (=> qxQ -> g qx ... Q)
+ std::swap(new_ev.outgoing[0].type, new_ev.outgoing[1].type);
+ // => uno gluon connects to quark colour
+ new_expected[3] = expected_colours[2];
+ new_expected[2] = {expected_colours[0].second+2, expected_colours[0].second};
+ check_event(new_ev, new_expected);
+
+ /// swap qx <-> q (=> qQ -> g q ... Q)
+ new_ev.incoming[0].type = HEJ::ParticleID::u;
+ new_ev.outgoing[1].type = HEJ::ParticleID::u;
+ // => swap: colour<->anti && inital<->final
+ std::swap(new_expected[0], new_expected[3]);
+ std::swap(new_expected[0].first, new_expected[0].second);
+ std::swap(new_expected[3].first, new_expected[3].second);
+ // => & connect first gluon with remaining anti-colour
+ new_expected[2] = {new_expected[0].first, new_expected[0].first+2};
+ // shift colour line one down
+ new_expected[1].first-=2;
+ new_expected[5].first-=2;
+ new_expected[5].second-=2;
+ // shift anti-colour line one up
+ new_expected[6].first+=2;
+ check_event(new_ev, new_expected);
+ }
+
+ {
+ // don't overwrite
+ auto new_expected = expected_colours;
+ auto new_ev = ev;
+ /// uno forward (=> qxQ -> qx ... Q g)
+ std::swap(new_ev.outgoing[3].type, new_ev.outgoing[4].type);
+ // => uno gluon connects to remaining colour
+ new_expected[5] = expected_colours[6];
+ new_expected[6] = {expected_colours[3].first+2, expected_colours[3].first};
+ check_event(new_ev, new_expected);
+ }
+
+ /// @TODO add qqx test when implemented (it should work)
+
+ return EXIT_SUCCESS;
+}
diff --git a/t/test_descriptions.cc b/t/test_descriptions.cc
index d212ad5..30c66a6 100644
--- a/t/test_descriptions.cc
+++ b/t/test_descriptions.cc
@@ -1,62 +1,62 @@
#include <iostream>
#include <cstddef>
#include "HEJ/Event.hh"
#include "HEJ/EventReweighter.hh"
#include "HEJ/ScaleFunction.hh"
#define ASSERT(x) if(!(x)) { \
std::cerr << "Assertion '" #x "' failed.\n"; \
return EXIT_FAILURE; \
}
int main() {
constexpr double mu = 125.;
HEJ::ScaleFunction fun{"125", HEJ::FixedScale{mu}};
ASSERT(fun.name() == "125");
HEJ::ScaleGenerator scale_gen{
{std::move(fun)}, {0.5, 1, 2.}, 2.1
};
- HEJ::UnclusteredEvent tmp;
+ HEJ::Event::EventData tmp;
tmp.outgoing.push_back(
- {HEJ::ParticleID::gluon, fastjet::PtYPhiM(50., -1., 0.3, 0.)}
+ {HEJ::ParticleID::gluon, fastjet::PtYPhiM(50., -1., 0.3, 0.), {}}
);
tmp.outgoing.push_back(
- {HEJ::ParticleID::gluon, fastjet::PtYPhiM(30., 1., -0.3, 0.)}
+ {HEJ::ParticleID::gluon, fastjet::PtYPhiM(30., 1., -0.3, 0.), {}}
);
HEJ::Event ev{
- std::move(tmp),
- fastjet::JetDefinition{fastjet::kt_algorithm, 0.4},
- 20.
+ tmp.cluster(
+ fastjet::JetDefinition{fastjet::kt_algorithm, 0.4}, 20.
+ )
};
auto rescaled = scale_gen(std::move(ev));
ASSERT(rescaled.central().description->scale_name == "125");
for(auto const & var: rescaled.variations()) {
ASSERT(var.description->scale_name == "125");
}
ASSERT(rescaled.central().description->mur_factor == 1.);
ASSERT(rescaled.central().description->muf_factor == 1.);
ASSERT(rescaled.variations(0).description->mur_factor == 1.);
ASSERT(rescaled.variations(0).description->muf_factor == 1.);
ASSERT(rescaled.variations(1).description->mur_factor == 0.5);
ASSERT(rescaled.variations(1).description->muf_factor == 0.5);
ASSERT(rescaled.variations(2).description->mur_factor == 0.5);
ASSERT(rescaled.variations(2).description->muf_factor == 1.);
ASSERT(rescaled.variations(3).description->mur_factor == 1.);
ASSERT(rescaled.variations(3).description->muf_factor == 0.5);
ASSERT(rescaled.variations(4).description->mur_factor == 1.);
ASSERT(rescaled.variations(4).description->muf_factor == 2.);
ASSERT(rescaled.variations(5).description->mur_factor == 2.);
ASSERT(rescaled.variations(5).description->muf_factor == 1.);
ASSERT(rescaled.variations(6).description->mur_factor == 2.);
ASSERT(rescaled.variations(6).description->muf_factor == 2.);
}
diff --git a/t/test_parameters.cc b/t/test_parameters.cc
new file mode 100644
index 0000000..2261167
--- /dev/null
+++ b/t/test_parameters.cc
@@ -0,0 +1,71 @@
+#include <iostream>
+#include <stdexcept>
+
+#include "HEJ/Parameters.hh"
+
+#define ASSERT(x) if(!(x)) { \
+ throw std::logic_error("Assertion '" #x "' failed."); \
+ }
+
+
+namespace {
+ bool same_description(
+ HEJ::EventParameters const & par1, HEJ::EventParameters const & par2
+ ){
+ if( par1.mur!=par2.mur || par1.muf!=par2.muf ) return false;
+ auto const & des1 = par1.description;
+ auto const & des2 = par2.description;
+ if(bool(des1) != bool(des2)) return false; // only one set
+ if(!des1) return true; // both not set
+ return (des1->mur_factor == des2->mur_factor)
+ && (des1->muf_factor == des2->muf_factor)
+ && (des1->scale_name == des2->scale_name);
+ }
+
+ void same_description(
+ HEJ::Parameters<HEJ::EventParameters> const & par1,
+ HEJ::Parameters<HEJ::EventParameters> const & par2
+ ){
+ ASSERT(same_description(par1.central, par2.central));
+ ASSERT(par1.variations.size() == par2.variations.size());
+ for(size_t i=0; i<par1.variations.size(); ++i)
+ ASSERT( same_description(par1.variations[i], par2.variations[i]) );
+ }
+}
+
+int main() {
+ HEJ::Parameters<HEJ::EventParameters> ev_param;
+ ev_param.central = HEJ::EventParameters{ 1,1,1.1,
+ std::make_shared<HEJ::ParameterDescription>("a", 1.,1.) };
+ ev_param.variations.emplace_back(
+ HEJ::EventParameters{ 2,2,2.2,
+ std::make_shared<HEJ::ParameterDescription>("b", 2.,2.)
+ });
+ ev_param.variations.emplace_back(
+ HEJ::EventParameters{ 3,3,3.3,
+ std::make_shared<HEJ::ParameterDescription>("c", 3.,3.)
+ });
+
+ HEJ::Weights weights;
+ weights.central = 4.4;
+ weights.variations.push_back(5.5);
+ weights.variations.push_back(6.6);
+
+ HEJ::Parameters<HEJ::EventParameters> mult_param;
+ mult_param = ev_param*weights;
+ same_description(ev_param, mult_param);
+ ASSERT(mult_param.central.weight == ev_param.central.weight*weights.central);
+ for(size_t i=0; i<weights.variations.size(); ++i)
+ ASSERT(mult_param.variations[i].weight
+ == ev_param.variations[i].weight*weights.variations[i]);
+
+ HEJ::Parameters<HEJ::EventParameters> div_param;
+ div_param = ev_param/weights;
+ same_description(ev_param, div_param);
+ ASSERT(div_param.central.weight == ev_param.central.weight/weights.central);
+ for(size_t i=0; i<weights.variations.size(); ++i)
+ ASSERT(div_param.variations[i].weight
+ == ev_param.variations[i].weight/weights.variations[i]);
+
+ return EXIT_SUCCESS;
+}
diff --git a/t/test_psp.cc b/t/test_psp.cc
index 0d6f486..87355c6 100644
--- a/t/test_psp.cc
+++ b/t/test_psp.cc
@@ -1,69 +1,65 @@
#include "LHEF/LHEF.h"
#include "HEJ/stream.hh"
#include "HEJ/config.hh"
#include "HEJ/event_types.hh"
#include "HEJ/Event.hh"
#include "HEJ/PhaseSpacePoint.hh"
#include "HEJ/Ranlux64.hh"
namespace{
constexpr int max_trials = 100;
constexpr double extpartonptmin = 45.;
constexpr double max_ext_soft_pt_fraction =
std::numeric_limits<double>::infinity();
const fastjet::JetDefinition jet_def{fastjet::kt_algorithm, 0.4};
constexpr double min_jet_pt = 50;
};
int main(int argn, char** argv) {
if(argn != 2){
- std::cerr << "Usage: test_psp eventfile";
+ std::cerr << "Usage: " << argv[0] << " eventfile";
return EXIT_FAILURE;
}
HEJ::istream in{argv[1]};
LHEF::Reader reader{in};
LHEF::Writer writer{std::cerr};
writer.heprup = reader.heprup;
HEJ::PhaseSpacePointConfig conf;
conf.jet_param = HEJ::JetParameters{jet_def, min_jet_pt};
conf.min_extparton_pt = extpartonptmin;
conf.max_ext_soft_pt_fraction = max_ext_soft_pt_fraction;
HEJ::Ranlux64 ran{};
while(reader.readEvent()){
const HEJ::Event ev{
- HEJ::UnclusteredEvent{reader.hepeup},
- jet_def, min_jet_pt
+ HEJ::Event::EventData{reader.hepeup}( jet_def, min_jet_pt )
};
for(int trial = 0; trial < max_trials; ++trial){
HEJ::PhaseSpacePoint psp{ev, conf, ran};
if(psp.weight() != 0){
- HEJ::UnclusteredEvent tmp_ev;
+ HEJ::Event::EventData tmp_ev;
tmp_ev.incoming = psp.incoming();
tmp_ev.outgoing = psp.outgoing();
- tmp_ev.central = {0,0,0};
- HEJ::Event out_ev{
- std::move(tmp_ev),
- jet_def, min_jet_pt
- };
+ tmp_ev.parameters.central = {0,0,0};
+ HEJ::Event out_ev{ tmp_ev(jet_def, min_jet_pt) };
if(out_ev.type() != ev.type()){
using HEJ::event_type::names;
std::cerr << "Wrong class of phase space point:\n"
"original event of class " << names[ev.type()] << ":\n";
writer.hepeup = reader.hepeup;
writer.writeEvent();
std::cerr << "Phase space point of class " << names[out_ev.type()] << ":\n";
writer.hepeup = to_HEPEUP(out_ev, &writer.heprup);
writer.writeEvent();
return EXIT_FAILURE;
}
}
}
}
}
diff --git a/t/test_scale_arithmetics.cc b/t/test_scale_arithmetics.cc
index 015dd6a..b640726 100644
--- a/t/test_scale_arithmetics.cc
+++ b/t/test_scale_arithmetics.cc
@@ -1,87 +1,99 @@
// Generic tester for the ME for a given set of PSP
// reference weights and PSP (as LHE file) have to be given as _individual_ files
#include <fstream>
+#include <random>
+#include <algorithm>
#include "LHEF/LHEF.h"
#include "HEJ/EventReweighter.hh"
#include "HEJ/make_RNG.hh"
#include "HEJ/Event.hh"
#include "HEJ/YAMLreader.hh"
#include "HEJ/stream.hh"
constexpr double alpha_s = 0.118;
constexpr double ep = 1e-13;
void dump(HEJ::Event const & ev){
{
LHEF::Writer writer{std::cout};
std::cout << std::setprecision(6);
writer.hepeup = to_HEPEUP(std::move(ev), nullptr);
writer.writeEvent();
}
std::cout << "Rapidity ordering:\n";
for(const auto & part: ev.outgoing()){
std::cout << std::setw(2) << part.type << ": "<< std::setw(7) << part.rapidity() << std::endl;
}
}
+void shuffle_particles(HEJ::Event::EventData & ev) {
+ static std::mt19937_64 ran{0};
+ std::shuffle(begin(ev.incoming), end(ev.incoming), ran);
+ std::shuffle(begin(ev.outgoing), end(ev.outgoing), ran);
+}
+
int main(int argn, char** argv){
if(argn != 3){
std::cerr << "\n# Usage:\n."<< argv[0] <<" config.yml input_file.lhe\n\n";
return EXIT_FAILURE;
}
HEJ::Config config = HEJ::load_config(argv[1]);
config.scales = HEJ::to_ScaleConfig(
YAML::Load("scales: [H_T, 1 * H_T, 2/2 * H_T, 2*H_T/2, H_T/2*2, H_T/2/2*4, H_T*H_T/H_T]")
);
HEJ::istream in{argv[2]};
LHEF::Reader reader{in};
auto ran = HEJ::make_RNG(config.rng.name, config.rng.seed);
HEJ::ScaleGenerator scale_gen{
config.scales.base,
config.scales.factors,
config.scales.max_ratio
};
HEJ::EventReweighter resum{
reader.heprup,
std::move(scale_gen),
to_EventReweighterConfig(config),
*ran
};
size_t i = 0;
while(reader.readEvent()){
++i;
+ HEJ::Event::EventData data{reader.hepeup};
+ shuffle_particles(data);
+
HEJ::Event event{
- HEJ::UnclusteredEvent{reader.hepeup},
- config.resummation_jets.def,
- config.resummation_jets.min_pt
+ data.cluster(
+ config.resummation_jets.def,
+ config.resummation_jets.min_pt
+ )
};
auto resummed = resum.reweight(event, config.trials);
for(auto && ev: resummed) {
for(auto &&var: ev.variations()) {
if(std::abs(var.muf - ev.central().muf) > ep) {
std::cerr
<< std::setprecision(15)
<< "unequal scales: " << var.muf
<< " != " << ev.central().muf << '\n'
<< "in resummed event:\n";
dump(ev);
std::cerr << "\noriginal event:\n";
dump(event);
return EXIT_FAILURE;
}
}
}
}
}
diff --git a/t/test_scale_import.cc b/t/test_scale_import.cc
index 7a194c3..0b3fd88 100644
--- a/t/test_scale_import.cc
+++ b/t/test_scale_import.cc
@@ -1,31 +1,29 @@
#include <stdexcept>
#include <iostream>
#include "HEJ/YAMLreader.hh"
#include "HEJ/Event.hh"
int main(int argc, char** argv) {
constexpr double ep = 1e-7;
if (argc != 2) {
throw std::logic_error{"wrong number of args"};
}
const HEJ::Config config = HEJ::load_config(argv[1]);
- HEJ::UnclusteredEvent tmp;
+ HEJ::Event::EventData tmp;
tmp.outgoing.push_back(
- {HEJ::ParticleID::gluon, fastjet::PtYPhiM(50., -1., 0.3, 0.)}
+ {HEJ::ParticleID::gluon, fastjet::PtYPhiM(50., -1., 0.3, 0.), {}}
);
tmp.outgoing.push_back(
- {HEJ::ParticleID::gluon, fastjet::PtYPhiM(30., 1., -0.3, 0.)}
+ {HEJ::ParticleID::gluon, fastjet::PtYPhiM(30., 1., -0.3, 0.), {}}
);
HEJ::Event ev{
- std::move(tmp),
- fastjet::JetDefinition{fastjet::kt_algorithm, 0.4},
- 20.
+ tmp(fastjet::JetDefinition{fastjet::kt_algorithm, 0.4}, 20.)
};
const double softest_pt = config.scales.base[0](ev);
if(std::abs(softest_pt-30.) > ep){
throw std::logic_error{"wrong softest pt"};
}
}

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