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diff --git a/doc/sphinx/HEJFOG.rst b/doc/sphinx/HEJFOG.rst
index 7060893..91260ab 100644
--- a/doc/sphinx/HEJFOG.rst
+++ b/doc/sphinx/HEJFOG.rst
@@ -1,291 +1,291 @@
The HEJ Fixed Order Generator
=============================
For high jet multiplicities event generation with standard fixed-order
generators becomes increasingly cumbersome. For example, the
leading-order production of a Higgs Boson with five or more jets is
computationally prohibitively expensive.
To this end, HEJ 2 provides the ``HEJFOG`` fixed-order generator
that allows to generate events with high jet multiplicities. To
facilitate the computation the limit of Multi-Regge Kinematics with
large invariant masses between all outgoing particles is assumed in the
matrix elements. The typical use of the ``HEJFOG`` is to supplement
low-multiplicity events from standard generators with high-multiplicity
events before using the HEJ 2 program to add high-energy
resummation.
Installation
------------
The ``HEJFOG`` comes bundled together with HEJ 2 and the
installation is very similar. After downloading HEJ 2 and
installing the prerequisites as described in :ref:`Installation` the
``HEJFOG`` can be installed with::
- cmake /path/to/FixedOrderGen -DCMAKE_INSTALL_PREFIX=target/directory -DCMAKE_BUILD_TYPE=Release
+ cmake /path/to/FixedOrderGen -DCMAKE_INSTALL_PREFIX=target/directory
make install
where :file:`/path/to/FixedOrderGen` refers to the :file:`FixedOrderGen`
subdirectory in the HEJ 2 directory. If HEJ 2 was
installed to a non-standard location, it may be necessary to specify the
directory containing :file:`HEJ-config.cmake`. If the base installation
directory is :file:`/path/to/HEJ`, :file:`HEJ-config.cmake` should be
found in :file:`/path/to/HEJ/lib/cmake/HEJ` and the commands for
installing the ``HEJFOG`` would read::
cmake /path/to/FixedOrderGen -DHEJ_DIR=/path/to/HEJ/lib/cmake/HEJ -DCMAKE_INSTALL_PREFIX=target/directory
make install
The installation can be tested with::
make test
-provided that the NNPDF 3.0 PDF set is installed.
+provided that the CT10nlo PDF set is installed.
Running the fixed-order generator
---------------------------------
After installing the ``HEJFOG`` you can modify the provided
configuration file :file:`configFO.yml` and run the generator with::
HEJFOG configFO.yml
The resulting event file, by default named :file:`HEJFO.lhe`, can then be
fed into HEJ 2 like any event file generated from a standard
fixed-order generator, see :ref:`Running HEJ 2`.
Settings
--------
Similar to HEJ 2, the ``HEJFOG`` uses a `YAML
<http://yaml.org/>`_ configuration file. The settings are
.. _`process`:
**process**
The scattering process for which events are being generated. The
format is
:code:`in1 in2 => out1 out2 ...`
The incoming particles, :code:`in1`, :code:`in2` can be
- quarks: :code:`u`, :code:`d`, :code:`u_bar`, and so on
- gluons: :code:`g`
- protons :code:`p` or antiprotons :code:`p_bar`
At most one of the outgoing particles can be a boson, the rest has to be
partonic. At the moment only the Higgs boson :code:`h` is supported. All
other outgoing particles are jets. Multiple jets can be grouped together, so
:code:`p p => h j j` is the same as :code:`p p => h 2j`. There have to be at
least two jets. Further decays of the boson can be added through the
:ref:`particle properties<particle properties: particle: decays>`.
.. _`events`:
**events**
Specifies the number of events to generate.
.. _`jets`:
**jets**
Defines the properties of the generated jets.
.. _`jets: min pt`:
**min pt**
Minimum jet transverse momentum in GeV.
.. _`jets: peak pt`:
**peak pt**
Optional setting to specify the dominant jet transverse momentum
in GeV. If the generated events are used as input for HEJ
resummation, this should be set to the minimum transverse momentum
of the resummation jets. The effect is that only a small fraction
of jets will be generated with a transverse momentum below the
value of this setting.
.. _`jets: algorithm`:
**algorithm**
The algorithm used to define jets. Allowed settings are
:code:`kt`, :code:`cambridge`, :code:`antikt`,
:code:`cambridge for passive`. See the `FastJet
<http://fastjet.fr/>`_ documentation for a description of these
algorithms.
.. _`jets: R`:
**R**
The R parameter used in the jet algorithm.
.. _`jets: max rapidity`:
**max rapidity**
Maximum absolute value of the jet rapidity.
.. _`beam`:
**beam**
Defines various properties of the collider beam.
.. _`beam: energy`:
**energy**
The beam energy in GeV. For example, the 13
TeV LHC corresponds to a value of 6500.
.. _`beam: particles`:
**particles**
A list :code:`[p1, p2]` of two beam particles. The only supported
entries are protons :code:`p` and antiprotons :code:`p_bar`.
.. _`pdf`:
**pdf**
The `LHAPDF number <https://lhapdf.hepforge.org/pdfsets>`_ of the PDF set.
For example, 230000 corresponds to an NNPDF 2.3 NLO PDF set.
.. _`subleading fraction`:
**subleading fraction**
This setting is related to the fraction of events that are not FKL
configurations and thus subleading in the high-energy
limit. Currently only unordered emissions are implemented, and only
for Higgs boson plus multijet processes. This value must be positive
and not larger than 1. It should typically be chosen between 0.01 and
0.1. Note that while this parameter influences the chance of
generating subleading configurations, it generally does not
correspond to the actual fraction of subleading events.
.. _`subleading channels`:
**subleading channels**
Optional parameter to select the production of specific channels that
are subleading in the high-energy limit. Only has an effect if
:code:`subleading fraction` is non-zero. Currently three values are
supported:
- :code:`all`: All subleading channels are allowed. This is the default.
- :code:`none`: No subleading contribution, only FKL configurations
are allowed. This is equivalent to :code:`subleading fraction: 0`.
- :code:`unordered`: Unordered emission are allowed.
Unordered emission are any rapidity ordering where exactly one
gluon is emitted outside the FKL rapidity ordering. More
precisely, if at least one of the incoming particles is a quark or
antiquark and there are more than two jets in the final state,
:code:`subleading fraction` states the probability that the
flavours of the outgoing particles are assigned in such a way that
an unordered configuration arises.
.. _`unweight`:
**unweight**
This setting defines the parameters for the partial unweighting of
events. You can disable unweighting by removing this entry from the
configuration file.
.. _`unweight: sample size`:
**sample size**
The number of weighted events used to calibrate the unweighting.
A good default is to set this to the number of target
`events`_. If the number of `events`_ is large this can
lead to significant memory consumption and a lower value should be
chosen. Contrarily, for large multiplicities the unweighting
efficiency becomes worse and the sample size should be increased.
.. _`unweight: max deviation`:
**max deviation**
Controls the range of events to which unweighting is applied. A
larger value means that a larger fraction of events are unweighted.
Typical values are between -1 and 1.
.. _`particle properties`:
**particle properties**
Specifies various properties of the different particles (Higgs, W or Z).
This is only relevant if the chosen `process`_ is the production of the
corresponding particles with jets. E.g. for the `process`_
:code:`p p => h 2j` the :code:`mass`, :code:`width` and (optionally)
:code:`decays` of the :code:`Higgs` boson are required, while all other
particle properties will be ignored.
.. _`particle properties: particle`:
**Higgs, W+, W- or Z**
The particle (Higgs, |W+|, |W-|, Z) for which the following
properties are defined.
.. |W+| replace:: W\ :sup:`+`
.. |W-| replace:: W\ :sup:`-`
.. _`particle properties: particle: mass`:
**mass**
The mass of the particle in GeV.
.. _`particle properties: particle: width`:
**width**
The total decay width of the particle in GeV.
.. _`particle properties: particle: decays`:
**decays**
Optional setting specifying the decays of the particle. Only the decay
into two particles is implemented. Each decay has the form
:code:`{into: [p1,p2], branching ratio: r}`
where :code:`p1` and :code:`p2` are the particle names of the
decay product (e.g. :code:`photon`) and :code:`r` is the branching
ratio.
Decays of a Higgs boson are treated as the production and subsequent
decay of an on-shell Higgs boson, so decays into e.g. Z bosons are not
supported.
.. _`scales`:
**scales**
Specifies the renormalisation and factorisation scales for the output
events. For details, see the corresponding entry in the HEJ 2
:ref:`HEJ 2 settings`. Note that this should usually be a
single value, as the weights resulting from additional scale choices
will simply be ignored when adding high-energy resummation with HEJ 2.
.. _`event output`:
**event output**
Specifies the name of a single event output file or a list of such
files. See the corresponding entry in the HEJ 2
:ref:`HEJ 2 settings` for details.
.. _`RanLux init`:
.. _`random generator`:
**random generator**
Sets parameters for random number generation. See the HEJ 2
:ref:`HEJ 2 settings` for details.
.. _`analysis`:
**analysis**
Specifies the name and settings for a custom analysis library. This
can be useful to specify cuts at the fixed-order level. See the
corresponding entry in the HEJ 2 :ref:`HEJ 2 settings`
for details.
.. _`Higgs coupling`:
**Higgs coupling**
This collects a number of settings concerning the effective coupling
of the Higgs boson to gluons. See the corresponding entry in the
HEJ 2 :ref:`HEJ 2 settings` for details.
diff --git a/doc/sphinx/installation.rst b/doc/sphinx/installation.rst
index b77aa0b..016415f 100644
--- a/doc/sphinx/installation.rst
+++ b/doc/sphinx/installation.rst
@@ -1,63 +1,63 @@
.. _Installation:
Installation
============
Download
--------
HEJ 2 is developed using the `git version control system
<https://git-scm.com/>`_. To get a copy of HEJ 2, install git and
run::
- git clone https://gitlab.dur.scotgrid.ac.uk/hej/hej
+ git clone https://phab.hepforge.org/source/hej.git
Prerequisites
-------------
Before installing HEJ 2, you need the following programs and
libraries:
- `CMake <https://cmake.org/>`_ version 3.1
- A compiler supporting the C++14 standard, for example `gcc <https://gcc.gnu.org/>`_ 5 or later
- `FastJet <http://fastjet.fr/>`_
- `CLHEP <https://gitlab.cern.ch/CLHEP/CLHEP>`_
- `LHAPDF <https://lhapdf.hepforge.org/>`_
- The `IOStreams` and `uBLAS` `boost <https://www.boost.org>`_ libraries
- `yaml-cpp <https://github.com/jbeder/yaml-cpp>`_
If you want to include finite top mass corrections in Higgs boson + jets
production, you additionally need version 2 of the `QCDLoop
<https://github.com/scarrazza/qcdloop>`_ library. HEJ 2 supports
versions 2 and 3 of `HepMC <https://hepmc.web.cern.ch/hepmc/>`_ if it is
installed, but does not require it.
Compilation
-----------
To compile and install HEJ 2 run::
cmake source/directory -DCMAKE_INSTALL_PREFIX=target/directory
make install
:file:`source/directory` is the directory containing the file
:file:`CMakeLists.txt`. If you omit
:code:`-DCMAKE_INSTALL_PREFIX=target/directory` HEJ 2 will be
installed to some default location.
In case some of the aforementioned prerequisites are not found by
:code:`cmake` you can give a hint by adding an additional argument
:code:`-Dlibname_ROOT_DIR=/directory/with/library`, where
:code:`libname` should be replaced by the name of the library in
question.
Testing
-------
To test your installation, download the NNPDF 2.3 PDF set with::
lhapdf install NNPDF23_nlo_as_0119
and run::
make test

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