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diff --git a/Shower/Core/Base/SudakovFormFactor.cc b/Shower/Core/Base/SudakovFormFactor.cc
--- a/Shower/Core/Base/SudakovFormFactor.cc
+++ b/Shower/Core/Base/SudakovFormFactor.cc
@@ -1,367 +1,364 @@
// -*- C++ -*-
//
// SudakovFormFactor.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 SudakovFormFactor class.
//
#include "SudakovFormFactor.h"
#include "ThePEG/Interface/ClassDocumentation.h"
#include "ThePEG/Persistency/PersistentOStream.h"
#include "ThePEG/Persistency/PersistentIStream.h"
#include "ThePEG/Interface/Reference.h"
#include "ThePEG/Interface/Switch.h"
#include "ThePEG/Interface/Parameter.h"
#include "ShowerKinematics.h"
#include "ShowerParticle.h"
#include "ThePEG/Utilities/DescribeClass.h"
#include "Herwig/Shower/ShowerHandler.h"
using namespace Herwig;
DescribeAbstractClass<SudakovFormFactor,Interfaced>
describeSudakovFormFactor ("Herwig::SudakovFormFactor","");
void SudakovFormFactor::persistentOutput(PersistentOStream & os) const {
os << splittingFn_ << alpha_ << pdfmax_ << particles_ << pdffactor_
<< a_ << b_ << ounit(c_,GeV) << ounit(kinCutoffScale_,GeV) << cutOffOption_
<< ounit(vgcut_,GeV) << ounit(vqcut_,GeV)
- << ounit(pTmin_,GeV) << ounit(pT2min_,GeV2)
- << theFactorizationScaleFactor << theRenormalizationScaleFactor;
+ << ounit(pTmin_,GeV) << ounit(pT2min_,GeV2);
}
void SudakovFormFactor::persistentInput(PersistentIStream & is, int) {
is >> splittingFn_ >> alpha_ >> pdfmax_ >> particles_ >> pdffactor_
>> a_ >> b_ >> iunit(c_,GeV) >> iunit(kinCutoffScale_,GeV) >> cutOffOption_
>> iunit(vgcut_,GeV) >> iunit(vqcut_,GeV)
- >> iunit(pTmin_,GeV) >> iunit(pT2min_,GeV2)
- >> theFactorizationScaleFactor >> theRenormalizationScaleFactor;
+ >> iunit(pTmin_,GeV) >> iunit(pT2min_,GeV2);
}
void SudakovFormFactor::Init() {
static ClassDocumentation<SudakovFormFactor> documentation
("The SudakovFormFactor class is the base class for the implementation of Sudakov"
" form factors in Herwig");
static Reference<SudakovFormFactor,SplittingFunction>
interfaceSplittingFunction("SplittingFunction",
"A reference to the SplittingFunction object",
&Herwig::SudakovFormFactor::splittingFn_,
false, false, true, false);
static Reference<SudakovFormFactor,ShowerAlpha>
interfaceAlpha("Alpha",
"A reference to the Alpha object",
&Herwig::SudakovFormFactor::alpha_,
false, false, true, false);
static Parameter<SudakovFormFactor,double> interfacePDFmax
("PDFmax",
"Maximum value of PDF weight. ",
&SudakovFormFactor::pdfmax_, 35.0, 1.0, 1000000.0,
false, false, Interface::limited);
static Switch<SudakovFormFactor,unsigned int> interfacePDFFactor
("PDFFactor",
"Include additional factors in the overestimate for the PDFs",
&SudakovFormFactor::pdffactor_, 0, false, false);
static SwitchOption interfacePDFFactorNo
(interfacePDFFactor,
"No",
"Don't include any factors",
0);
static SwitchOption interfacePDFFactorOverZ
(interfacePDFFactor,
"OverZ",
"Include an additional factor of 1/z",
1);
static SwitchOption interfacePDFFactorOverOneMinusZ
(interfacePDFFactor,
"OverOneMinusZ",
"Include an additional factor of 1/(1-z)",
2);
static SwitchOption interfacePDFFactorOverZOneMinusZ
(interfacePDFFactor,
"OverZOneMinusZ",
"Include an additional factor of 1/z/(1-z)",
3);
static SwitchOption interfacePDFFactorOverRootZ
(interfacePDFFactor,
"OverRootZ",
"Include an additional factor of 1/sqrt(z)",
4);
static SwitchOption interfacePDFFactorRootZ
(interfacePDFFactor,
"RootZ",
"Include an additional factor of sqrt(z)",
5);
static Switch<SudakovFormFactor,unsigned int> interfaceCutOffOption
("CutOffOption",
"The type of cut-off to use to end the shower",
&SudakovFormFactor::cutOffOption_, 0, false, false);
static SwitchOption interfaceCutOffOptionDefault
(interfaceCutOffOption,
"Default",
"Use the standard Herwig cut-off on virtualities with the minimum"
" virtuality depending on the mass of the branching particle",
0);
static SwitchOption interfaceCutOffOptionFORTRAN
(interfaceCutOffOption,
"FORTRAN",
"Use a FORTRAN-like cut-off on virtualities",
1);
static SwitchOption interfaceCutOffOptionpT
(interfaceCutOffOption,
"pT",
"Use a cut on the minimum allowed pT",
2);
static Parameter<SudakovFormFactor,double> interfaceaParameter
("aParameter",
"The a parameter for the kinematic cut-off",
&SudakovFormFactor::a_, 0.3, -10.0, 10.0,
false, false, Interface::limited);
static Parameter<SudakovFormFactor,double> interfacebParameter
("bParameter",
"The b parameter for the kinematic cut-off",
&SudakovFormFactor::b_, 2.3, -10.0, 10.0,
false, false, Interface::limited);
static Parameter<SudakovFormFactor,Energy> interfacecParameter
("cParameter",
"The c parameter for the kinematic cut-off",
&SudakovFormFactor::c_, GeV, 0.3*GeV, 0.1*GeV, 10.0*GeV,
false, false, Interface::limited);
static Parameter<SudakovFormFactor,Energy>
interfaceKinScale ("cutoffKinScale",
"kinematic cutoff scale for the parton shower phase"
" space (unit [GeV])",
&SudakovFormFactor::kinCutoffScale_, GeV,
2.3*GeV, 0.001*GeV, 10.0*GeV,false,false,false);
static Parameter<SudakovFormFactor,Energy> interfaceGluonVirtualityCut
("GluonVirtualityCut",
"For the FORTRAN cut-off option the minimum virtuality of the gluon",
&SudakovFormFactor::vgcut_, GeV, 0.85*GeV, 0.1*GeV, 10.0*GeV,
false, false, Interface::limited);
static Parameter<SudakovFormFactor,Energy> interfaceQuarkVirtualityCut
("QuarkVirtualityCut",
"For the FORTRAN cut-off option the minimum virtuality added to"
" the mass for particles other than the gluon",
&SudakovFormFactor::vqcut_, GeV, 0.85*GeV, 0.1*GeV, 10.0*GeV,
false, false, Interface::limited);
static Parameter<SudakovFormFactor,Energy> interfacepTmin
("pTmin",
"The minimum pT if using a cut-off on the pT",
&SudakovFormFactor::pTmin_, GeV, 1.0*GeV, ZERO, 10.0*GeV,
false, false, Interface::limited);
}
bool SudakovFormFactor::alphaSVeto(Energy2 pt2) const {
double ratio=alphaSVetoRatio(pt2,1.);
return UseRandom::rnd() > ratio;
}
double SudakovFormFactor::alphaSVetoRatio(Energy2 pt2, double factor) const {
- factor *= renormalizationScaleFactor();
+ factor *= ShowerHandler::currentHandler()->renormalizationScaleFactor();
return ThePEG::Math::powi(alpha_->ratio(pt2, factor),
splittingFn_->interactionOrder());
}
bool SudakovFormFactor::PDFVeto(const Energy2 t, const double x,
const tcPDPtr parton0, const tcPDPtr parton1,
Ptr<BeamParticleData>::transient_const_pointer beam) const {
double ratio=PDFVetoRatio(t,x,parton0,parton1,beam,1.);
return UseRandom::rnd() > ratio;
}
double SudakovFormFactor::PDFVetoRatio(const Energy2 t, const double x,
const tcPDPtr parton0, const tcPDPtr parton1,
Ptr<BeamParticleData>::transient_const_pointer beam,double factor) const {
assert(pdf_);
-
- Energy2 theScale = t * sqr(factorizationScaleFactor()*factor);
+ Energy2 theScale = t * sqr(ShowerHandler::currentHandler()->factorizationScaleFactor()*factor);
if (theScale < sqr(freeze_)) theScale = sqr(freeze_);
double newpdf(0.0), oldpdf(0.0);
newpdf=pdf_->xfx(beam,parton0,theScale,x/z());
oldpdf=pdf_->xfx(beam,parton1,theScale,x);
if(newpdf<=0.) return 0.;
if(oldpdf<=0.) return 1.;
double ratio = newpdf/oldpdf;
double maxpdf = pdfmax_;
switch (pdffactor_) {
case 0:
break;
case 1:
maxpdf /= z();
break;
case 2:
maxpdf /= 1.-z();
break;
case 3:
maxpdf /= (z()*(1.-z()));
break;
case 4:
maxpdf /= sqrt(z());
break;
case 5:
maxpdf *= sqrt(z());
break;
default :
throw Exception() << "SudakovFormFactor::PDFVetoRatio invalid PDFfactor = "
<< pdffactor_ << Exception::runerror;
}
if (ratio > maxpdf) {
generator()->log() << "PDFVeto warning: Ratio > " << name()
<< ":PDFmax (by a factor of "
<< ratio/maxpdf <<") for "
<< parton0->PDGName() << " to "
<< parton1->PDGName() << "\n";
}
return ratio/maxpdf ;
}
void SudakovFormFactor::addSplitting(const IdList & in) {
bool add=true;
for(unsigned int ix=0;ix<particles_.size();++ix) {
if(particles_[ix].size()==in.size()) {
bool match=true;
for(unsigned int iy=0;iy<in.size();++iy) {
if(particles_[ix][iy]!=in[iy]) {
match=false;
break;
}
}
if(match) {
add=false;
break;
}
}
}
if(add) particles_.push_back(in);
}
void SudakovFormFactor::removeSplitting(const IdList & in) {
for(vector<IdList>::iterator it=particles_.begin();
it!=particles_.end();++it) {
if(it->size()==in.size()) {
bool match=true;
for(unsigned int iy=0;iy<in.size();++iy) {
if((*it)[iy]!=in[iy]) {
match=false;
break;
}
}
if(match) {
vector<IdList>::iterator itemp=it;
--itemp;
particles_.erase(it);
it = itemp;
}
}
}
}
Energy2 SudakovFormFactor::guesst(Energy2 t1,unsigned int iopt,
const IdList &ids,
double enhance,bool ident,
double detune) const {
unsigned int pdfopt = iopt!=1 ? 0 : pdffactor_;
double c =
1./((splittingFn_->integOverP(zlimits_.second,ids,pdfopt) -
splittingFn_->integOverP(zlimits_.first ,ids,pdfopt))*
alpha_->overestimateValue()/Constants::twopi*enhance*detune);
assert(iopt<=2);
if(iopt==1) {
c/=pdfmax_;
//symmetry of FS gluon splitting
if(ident) c*=0.5;
}
else if(iopt==2) c*=-1.;
if(splittingFn_->interactionOrder()==1) {
double r = UseRandom::rnd();
if(iopt!=2 || c*log(r)<log(Constants::MaxEnergy2/t1)) {
return t1*pow(r,c);
}
else
return Constants::MaxEnergy2;
}
else {
assert(false && "Units are dubious here.");
int nm(splittingFn()->interactionOrder()-1);
c/=Math::powi(alpha_->overestimateValue()/Constants::twopi,nm);
return t1 / pow (1. - nm*c*log(UseRandom::rnd())
* Math::powi(t1*UnitRemoval::InvE2,nm)
,1./double(nm));
}
}
double SudakovFormFactor::guessz (unsigned int iopt, const IdList &ids) const {
unsigned int pdfopt = iopt!=1 ? 0 : pdffactor_;
double lower = splittingFn_->integOverP(zlimits_.first,ids,pdfopt);
return splittingFn_->invIntegOverP
(lower + UseRandom::rnd()*(splittingFn_->integOverP(zlimits_.second,ids,pdfopt) -
lower),ids,pdfopt);
}
void SudakovFormFactor::doinit() {
Interfaced::doinit();
pT2min_ = cutOffOption()==2 ? sqr(pTmin_) : ZERO;
}
const vector<Energy> & SudakovFormFactor::virtualMasses(const IdList & ids) {
static vector<Energy> output;
output.clear();
if(cutOffOption() == 0) {
for(unsigned int ix=0;ix<ids.size();++ix)
output.push_back(ids[ix]->mass());
Energy kinCutoff=
kinematicCutOff(kinScale(),*std::max_element(output.begin(),output.end()));
for(unsigned int ix=0;ix<output.size();++ix)
output[ix]=max(kinCutoff,output[ix]);
}
else if(cutOffOption() == 1) {
for(unsigned int ix=0;ix<ids.size();++ix) {
output.push_back(ids[ix]->mass());
output.back() += ids[ix]->id()==ParticleID::g ? vgCut() : vqCut();
}
}
else if(cutOffOption() == 2) {
for(unsigned int ix=0;ix<ids.size();++ix)
output.push_back(ids[ix]->mass());
}
else {
throw Exception() << "Unknown option for the cut-off"
<< " in SudakovFormFactor::virtualMasses()"
<< Exception::runerror;
}
return output;
}

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