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diff --git a/Hadronization/ClusterHadronizationHandler.cc b/Hadronization/ClusterHadronizationHandler.cc
--- a/Hadronization/ClusterHadronizationHandler.cc
+++ b/Hadronization/ClusterHadronizationHandler.cc
@@ -1,304 +1,307 @@
// -*- C++ -*-
//
// ClusterHadronizationHandler.cc is a part of Herwig - A multi-purpose Monte Carlo event generator
// Copyright (C) 2002-2017 The Herwig Collaboration
//
// Herwig is licenced under version 3 of the GPL, see COPYING for details.
// Please respect the MCnet academic guidelines, see GUIDELINES for details.
//
//
// This is the implementation of the non-inlined, non-templated member
// functions of the ClusterHadronizationHandler class.
//
#include "ClusterHadronizationHandler.h"
#include <ThePEG/Interface/ClassDocumentation.h>
#include <ThePEG/Persistency/PersistentOStream.h>
#include <ThePEG/Persistency/PersistentIStream.h>
#include <ThePEG/Interface/Switch.h>
#include <ThePEG/Interface/Parameter.h>
#include <ThePEG/Interface/Reference.h>
#include <ThePEG/Handlers/EventHandler.h>
#include <ThePEG/Handlers/Hint.h>
#include <ThePEG/PDT/ParticleData.h>
#include <ThePEG/EventRecord/Particle.h>
#include <ThePEG/EventRecord/Step.h>
#include <ThePEG/PDT/PDT.h>
#include <ThePEG/PDT/EnumParticles.h>
#include <ThePEG/Utilities/Throw.h>
#include "Herwig/Utilities/EnumParticles.h"
#include "CluHadConfig.h"
#include "Cluster.h"
#include <ThePEG/Utilities/DescribeClass.h>
using namespace Herwig;
ClusterHadronizationHandler * ClusterHadronizationHandler::currentHandler_ = 0;
DescribeClass<ClusterHadronizationHandler,HadronizationHandler>
describeClusterHadronizationHandler("Herwig::ClusterHadronizationHandler","");
IBPtr ClusterHadronizationHandler::clone() const {
return new_ptr(*this);
}
IBPtr ClusterHadronizationHandler::fullclone() const {
return new_ptr(*this);
}
void ClusterHadronizationHandler::persistentOutput(PersistentOStream & os)
const {
os << _partonSplitter << _clusterFinder << _colourReconnector
<< _clusterFissioner << _lightClusterDecayer << _clusterDecayer
<< ounit(_minVirtuality2,GeV2) << ounit(_maxDisplacement,mm)
<< _underlyingEventHandler << _reduceToTwoComponents;
}
void ClusterHadronizationHandler::persistentInput(PersistentIStream & is, int) {
is >> _partonSplitter >> _clusterFinder >> _colourReconnector
>> _clusterFissioner >> _lightClusterDecayer >> _clusterDecayer
>> iunit(_minVirtuality2,GeV2) >> iunit(_maxDisplacement,mm)
>> _underlyingEventHandler >> _reduceToTwoComponents;
}
void ClusterHadronizationHandler::Init() {
static ClassDocumentation<ClusterHadronizationHandler> documentation
("This is the main handler class for the Cluster Hadronization",
"The hadronization was performed using the cluster model of \\cite{Webber:1983if}.",
"%\\cite{Webber:1983if}\n"
"\\bibitem{Webber:1983if}\n"
" B.~R.~Webber,\n"
" ``A QCD Model For Jet Fragmentation Including Soft Gluon Interference,''\n"
" Nucl.\\ Phys.\\ B {\\bf 238}, 492 (1984).\n"
" %%CITATION = NUPHA,B238,492;%%\n"
// main manual
);
static Reference<ClusterHadronizationHandler,PartonSplitter>
interfacePartonSplitter("PartonSplitter",
"A reference to the PartonSplitter object",
&Herwig::ClusterHadronizationHandler::_partonSplitter,
false, false, true, false);
static Reference<ClusterHadronizationHandler,ClusterFinder>
interfaceClusterFinder("ClusterFinder",
"A reference to the ClusterFinder object",
&Herwig::ClusterHadronizationHandler::_clusterFinder,
false, false, true, false);
static Reference<ClusterHadronizationHandler,ColourReconnector>
interfaceColourReconnector("ColourReconnector",
"A reference to the ColourReconnector object",
&Herwig::ClusterHadronizationHandler::_colourReconnector,
false, false, true, false);
static Reference<ClusterHadronizationHandler,ClusterFissioner>
interfaceClusterFissioner("ClusterFissioner",
"A reference to the ClusterFissioner object",
&Herwig::ClusterHadronizationHandler::_clusterFissioner,
false, false, true, false);
static Reference<ClusterHadronizationHandler,LightClusterDecayer>
interfaceLightClusterDecayer("LightClusterDecayer",
"A reference to the LightClusterDecayer object",
&Herwig::ClusterHadronizationHandler::_lightClusterDecayer,
false, false, true, false);
static Reference<ClusterHadronizationHandler,ClusterDecayer>
interfaceClusterDecayer("ClusterDecayer",
"A reference to the ClusterDecayer object",
&Herwig::ClusterHadronizationHandler::_clusterDecayer,
false, false, true, false);
static Parameter<ClusterHadronizationHandler,Energy2> interfaceMinVirtuality2
("MinVirtuality2",
"Minimum virtuality^2 of partons to use in calculating distances (unit [GeV2]).",
&ClusterHadronizationHandler::_minVirtuality2, GeV2, 0.1*GeV2, ZERO, 10.0*GeV2,false,false,false);
static Parameter<ClusterHadronizationHandler,Length> interfaceMaxDisplacement
("MaxDisplacement",
"Maximum displacement that is allowed for a particle (unit [millimeter]).",
&ClusterHadronizationHandler::_maxDisplacement, mm, 1.0e-10*mm,
0.0*mm, 1.0e-9*mm,false,false,false);
static Reference<ClusterHadronizationHandler,StepHandler> interfaceUnderlyingEventHandler
("UnderlyingEventHandler",
"Pointer to the handler for the Underlying Event. "
"Set to NULL to disable.",
&ClusterHadronizationHandler::_underlyingEventHandler, false, false, true, true, false);
static Switch<ClusterHadronizationHandler,bool> interfaceReduceToTwoComponents
("ReduceToTwoComponents",
"Whether or not to reduce three component baryon-number violating clusters to two components before cluster splitting or leave"
" this till after the cluster splitting",
&ClusterHadronizationHandler::_reduceToTwoComponents, true, false, false);
static SwitchOption interfaceReduceToTwoComponentsYes
(interfaceReduceToTwoComponents,
"BeforeSplitting",
"Reduce to two components",
true);
static SwitchOption interfaceReduceToTwoComponentsNo
(interfaceReduceToTwoComponents,
"AfterSplitting",
"Treat as three components",
false);
}
namespace {
void extractChildren(tPPtr p, set<PPtr> & all) {
if (p->children().empty()) return;
for (PVector::const_iterator child = p->children().begin();
child != p->children().end(); ++child) {
all.insert(*child);
extractChildren(*child, all);
}
}
}
void ClusterHadronizationHandler::
handle(EventHandler & ch, const tPVector & tagged,
const Hint &) {
useMe();
currentHandler_ = this;
PVector currentlist(tagged.begin(),tagged.end());
// set the scale for coloured particles to just above the gluon mass squared
// if less than this so they are classed as perturbative
Energy2 Q02 = 1.01*sqr(getParticleData(ParticleID::g)->constituentMass());
for(unsigned int ix=0;ix<currentlist.size();++ix) {
if(currentlist[ix]->scale()<Q02) currentlist[ix]->scale(Q02);
}
// split the gluons
_partonSplitter->split(currentlist);
// form the clusters
ClusterVector clusters =
_clusterFinder->formClusters(currentlist);
// reduce BV clusters to two components now if needed
if(_reduceToTwoComponents)
_clusterFinder->reduceToTwoComponents(clusters);
// perform colour reconnection if needed and then
// decay the clusters into one hadron
bool lightOK = false;
short tried = 0;
const ClusterVector savedclusters = clusters;
tPVector finalHadrons; // only needed for partonic decayer
while (!lightOK && tried++ < 10) {
// no colour reconnection with baryon-number-violating (BV) clusters
ClusterVector CRclusters, BVclusters;
CRclusters.reserve( clusters.size() );
BVclusters.reserve( clusters.size() );
for (size_t ic = 0; ic < clusters.size(); ++ic) {
ClusterPtr cl = clusters.at(ic);
bool hasClusterParent = false;
for (unsigned int ix=0; ix < cl->parents().size(); ++ix) {
if (cl->parents()[ix]->id() == ParticleID::Cluster) {
hasClusterParent = true;
break;
}
}
if (cl->numComponents() > 2 || hasClusterParent) BVclusters.push_back(cl);
else CRclusters.push_back(cl);
}
// colour reconnection
_colourReconnector->rearrange(CRclusters);
// tag new clusters as children of the partons to hadronize
_setChildren(CRclusters);
// forms diquarks
_clusterFinder->reduceToTwoComponents(CRclusters);
// recombine vectors of (possibly) reconnected and BV clusters
clusters.clear();
clusters.insert( clusters.end(), CRclusters.begin(), CRclusters.end() );
clusters.insert( clusters.end(), BVclusters.begin(), BVclusters.end() );
// fission of heavy clusters
// NB: during cluster fission, light hadrons might be produced straight away
finalHadrons = _clusterFissioner->fission(clusters,isSoftUnderlyingEventON());
// if clusters not previously reduced to two components do it now
if(!_reduceToTwoComponents)
_clusterFinder->reduceToTwoComponents(clusters);
lightOK = _lightClusterDecayer->decay(clusters,finalHadrons);
// if the decay of the light clusters was not successful, undo the cluster
// fission and decay steps and revert to the original state of the event
// record
if (!lightOK) {
clusters = savedclusters;
for_each(clusters.begin(),
clusters.end(),
mem_fun(&Particle::undecay));
}
}
if (!lightOK) {
throw Exception("CluHad::handle(): tried LightClusterDecayer 10 times!",
Exception::eventerror);
}
// decay the remaining clusters
_clusterDecayer->decay(clusters,finalHadrons);
// *****************************************
// *****************************************
// *****************************************
StepPtr pstep = newStep();
set<PPtr> allDecendants;
for (tPVector::const_iterator it = tagged.begin();
it != tagged.end(); ++it) {
extractChildren(*it, allDecendants);
}
for(set<PPtr>::const_iterator it = allDecendants.begin();
it != allDecendants.end(); ++it) {
// this is a workaround because the set sometimes
// re-orders parents after their children
if ((*it)->children().empty())
pstep->addDecayProduct(*it);
else {
pstep->addDecayProduct(*it);
pstep->addIntermediate(*it);
}
}
// *****************************************
// *****************************************
// *****************************************
// soft underlying event if needed
if (isSoftUnderlyingEventON()) {
assert(_underlyingEventHandler);
ch.performStep(_underlyingEventHandler,Hint::Default());
}
}
+
+// Sets parent child relationship of all clusters with two components
+// Relationships for clusters with more than two components are set elsewhere in the Colour Reconnector
void ClusterHadronizationHandler::_setChildren(const ClusterVector & clusters) const {
// erase existing information about the partons' children
tPVector partons;
for ( const auto & cl : clusters ) {
if ( cl->numComponents() > 2 ) continue;
partons.push_back( cl->colParticle() );
partons.push_back( cl->antiColParticle() );
}
// erase all previous information about parent child relationship
for_each(partons.begin(), partons.end(), mem_fun(&Particle::undecay));
// give new parents to the clusters: their constituents
for ( const auto & cl : clusters ) {
if ( cl->numComponents() > 2 ) continue;
cl->colParticle()->addChild(cl);
cl->antiColParticle()->addChild(cl);
}
}

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