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diff --git a/include/HEJ/MatrixElement.hh b/include/HEJ/MatrixElement.hh
index bcb760d..8df28b9 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/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_;
- const MatrixElementConfig param_;
+ MatrixElementConfig param_;
};
}

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