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diff --git a/Shower/SplittingFunctions/HalfHalfOneSplitFn.cc b/Shower/SplittingFunctions/HalfHalfOneSplitFn.cc
--- a/Shower/SplittingFunctions/HalfHalfOneSplitFn.cc
+++ b/Shower/SplittingFunctions/HalfHalfOneSplitFn.cc
@@ -1,129 +1,129 @@
// -*- C++ -*-
//
// HalfHalfOneSplitFn.cc is a part of Herwig++ - A multi-purpose Monte Carlo event generator
// Copyright (C) 2002-2011 The Herwig Collaboration
//
// Herwig++ is licenced under version 2 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 HalfHalfOneSplitFn class.
//
#include "HalfHalfOneSplitFn.h"
#include "ThePEG/PDT/ParticleData.h"
#include "ThePEG/Interface/ClassDocumentation.h"
#include "ThePEG/Utilities/DescribeClass.h"
#include "Herwig++/Shower/Base/ShowerParticle.h"
using namespace Herwig;
DescribeNoPIOClass<HalfHalfOneSplitFn,Herwig::SplittingFunction>
describeHalfHalfOneSplitFn ("Herwig::HalfHalfOneSplitFn","HwShower.so");
void HalfHalfOneSplitFn::Init() {
static ClassDocumentation<HalfHalfOneSplitFn> documentation
("The HalfHalfOneSplitFn class implements the q -> qg splitting function");
}
double HalfHalfOneSplitFn::P(const double z, const Energy2 t,
const IdList &ids, const bool mass) const {
double val = (1. + sqr(z))/(1.-z);
if(mass) {
Energy m = getParticleData(ids[0])->mass();
val -= 2.*sqr(m)/t;
}
return colourFactor(ids)*val;
}
double HalfHalfOneSplitFn::overestimateP(const double z,
const IdList & ids) const {
return 2.*colourFactor(ids)/(1.-z);
}
double HalfHalfOneSplitFn::ratioP(const double z, const Energy2 t,
const IdList & ids, const bool mass) const {
double val = 1. + sqr(z);
if(mass) {
Energy m = getParticleData(ids[0])->mass();
val -= 2.*sqr(m)*(1.-z)/t;
}
return 0.5*val;
}
double HalfHalfOneSplitFn::integOverP(const double z,
const IdList & ids,
unsigned int PDFfactor) const {
switch (PDFfactor) {
case 0:
return -2.*colourFactor(ids)*Math::log1m(z);
case 1:
return 2.*colourFactor(ids)*log(z/(1.-z));
case 2:
return 2.*colourFactor(ids)/(1.-z);
case 3:
default:
throw Exception() << "HalfHalfOneSplitFn::integOverP() invalid PDFfactor = "
<< PDFfactor << Exception::runerror;
}
}
double HalfHalfOneSplitFn::invIntegOverP(const double r, const IdList & ids,
unsigned int PDFfactor) const {
switch (PDFfactor) {
case 0:
return 1. - exp(- 0.5*r/colourFactor(ids));
case 1:
return 1./(1.-exp(-0.5*r/colourFactor(ids)));
case 2:
return 1.-2.*colourFactor(ids)/r;
case 3:
default:
throw Exception() << "HalfHalfOneSplitFn::invIntegOverP() invalid PDFfactor = "
<< PDFfactor << Exception::runerror;
}
}
bool HalfHalfOneSplitFn::accept(const IdList &ids) const {
// 3 particles and in and out fermion same
if(ids.size()!=3 || ids[0]!=ids[1]) return false;
tcPDPtr q=getParticleData(ids[0]);
tcPDPtr g=getParticleData(ids[2]);
if(q->iSpin()!=PDT::Spin1Half ||
g->iSpin()!=PDT::Spin1) return false;
return checkColours(ids);
}
vector<pair<int, Complex> >
HalfHalfOneSplitFn::generatePhi(ShowerParticle & ,ShoKinPtr ,
- const double z, const Energy2, const IdList & ,
+ const double, const Energy2, const IdList & ,
const RhoDMatrix &) {
// no dependence on the spin density matrix, dependence on off-diagonal terms cancels
// and rest = splitting function for Tr(rho)=1 as required by defn
return vector<pair<int, Complex> >(1,make_pair(0,1.));
}
-DecayMatrixElement HalfHalfOneSplitFn::matrixElement(ShowerParticle & particle,ShoKinPtr showerkin,
+DecayMatrixElement HalfHalfOneSplitFn::matrixElement(ShowerParticle & particle,ShoKinPtr,
const double z, const Energy2 t,
- const IdList & ids, const double phi) {
+ const IdList &, const double phi) {
// calculate the kernal
DecayMatrixElement kernal(PDT::Spin1Half,PDT::Spin1Half,PDT::Spin1);
Energy m = particle.dataPtr()->mass();
double mt = m/sqrt(t);
double root = sqrt(1.-(1.-z)*sqr(m)/z/t);
double romz = sqrt(1.-z);
double rz = sqrt(z);
Complex phase = exp(Complex(0.,1.)*phi);
kernal(0,0,0) = -root/romz*phase;
kernal(1,1,2) = -conj(kernal(0,0,0));
kernal(0,0,2) = root/romz*z/phase;
kernal(1,1,0) = -conj(kernal(0,0,2));
kernal(1,0,2) = mt*(1.-z)/rz;
kernal(0,1,0) = conj(kernal(1,0,2));
kernal(0,1,2) = 0.;
kernal(1,0,0) = 0.;
return kernal;
}
diff --git a/Shower/SplittingFunctions/OneHalfHalfSplitFn.cc b/Shower/SplittingFunctions/OneHalfHalfSplitFn.cc
--- a/Shower/SplittingFunctions/OneHalfHalfSplitFn.cc
+++ b/Shower/SplittingFunctions/OneHalfHalfSplitFn.cc
@@ -1,138 +1,137 @@
// -*- C++ -*-
//
// OneHalfHalfSplitFn.cc is a part of Herwig++ - A multi-purpose Monte Carlo event generator
// Copyright (C) 2002-2011 The Herwig Collaboration
//
// Herwig++ is licenced under version 2 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 OneHalfHalfSplitFn class.
//
#include "OneHalfHalfSplitFn.h"
#include "ThePEG/PDT/ParticleData.h"
#include "ThePEG/Interface/ClassDocumentation.h"
#include "ThePEG/Utilities/DescribeClass.h"
using namespace Herwig;
DescribeNoPIOClass<OneHalfHalfSplitFn,Herwig::SplittingFunction>
describeOneHalfHalfSplitFn ("Herwig::OneHalfHalfSplitFn","HwShower.so");
void OneHalfHalfSplitFn::Init() {
static ClassDocumentation<OneHalfHalfSplitFn> documentation
("The OneHalfHalfSplitFn class implements the splitting function for g->q qbar");
}
double OneHalfHalfSplitFn::P(const double z, const Energy2 t,
const IdList &ids, const bool mass) const {
double zz = z*(1.-z);
double val=1.-2.*zz;
if(mass) {
Energy m = getParticleData(ids[1])->mass();
val +=2.*sqr(m)/t;
}
return colourFactor(ids)*val;
}
double OneHalfHalfSplitFn::overestimateP(const double,
const IdList &ids) const {
return colourFactor(ids);
}
double OneHalfHalfSplitFn::ratioP(const double z, const Energy2 t,
const IdList &ids, const bool mass) const {
double zz = z*(1.-z);
double val = 1.-2.*zz;
if(mass) {
Energy m = getParticleData(ids[1])->mass();
val+= 2.*sqr(m)/t;
}
return val;
}
double OneHalfHalfSplitFn::integOverP(const double z, const IdList & ids,
unsigned int PDFfactor) const {
switch(PDFfactor) {
case 0:
return colourFactor(ids)*z;
case 1:
return colourFactor(ids)*log(z);
case 2:
return -colourFactor(ids)*log(1.-z);
case 3:
return colourFactor(ids)*log(z/(1.-z));
default:
throw Exception() << "OneHalfHalfSplitFn::integOverP() invalid PDFfactor = "
<< PDFfactor << Exception::runerror;
}
}
double OneHalfHalfSplitFn::invIntegOverP(const double r,
const IdList & ids,
unsigned int PDFfactor) const {
switch(PDFfactor) {
case 0:
return r/colourFactor(ids);
case 1:
return exp(r/colourFactor(ids));
case 2:
return 1.-exp(-r/colourFactor(ids));
case 3:
return 1./(1.+exp(-r/colourFactor(ids)));
default:
throw Exception() << "OneHalfHalfSplitFn::integOverP() invalid PDFfactor = "
<< PDFfactor << Exception::runerror;
}
}
bool OneHalfHalfSplitFn::accept(const IdList &ids) const {
if(ids.size()!=3) return false;
if(ids[1]!=-ids[2]) return false;
tcPDPtr q=getParticleData(ids[1]);
if(q->iSpin()!=PDT::Spin1Half) return false;
tcPDPtr g=getParticleData(ids[0]);
if(g->iSpin()!=PDT::Spin1) return false;
return checkColours(ids);
}
vector<pair<int, Complex> >
OneHalfHalfSplitFn::generatePhi(ShowerParticle & ,ShoKinPtr ,
const double z, const Energy2 t, const IdList & ids,
const RhoDMatrix & rho) {
assert(rho.iSpin()==PDT::Spin1);
double modRho = abs(rho(0,2));
Energy mq = getParticleData(ids[1])->mass();
Energy2 mq2 = sqr(mq);
double fact = z*(1.-z)-mq2/t;
double max = 1.+2.*fact*(-1.+2.*modRho);
vector<pair<int, Complex> > output;
output.push_back(make_pair( 0,(rho(0,0)+rho(2,2))*(1.-2.*fact)/max));
output.push_back(make_pair(-2,2.*fact*rho(0,2)/max));
output.push_back(make_pair( 2,2.*fact*rho(2,0)/max));
return output;
}
DecayMatrixElement OneHalfHalfSplitFn::matrixElement(ShowerParticle &,ShoKinPtr,
const double z, const Energy2 t,
const IdList & ids, const double phi) {
static const Complex ii(0.,1.);
// calculate the kernal
DecayMatrixElement kernal(PDT::Spin1,PDT::Spin1Half,PDT::Spin1Half);
double mt = getParticleData(ids[1])->mass()/sqrt(t);
- double mt = 0.;
double root = sqrt(1.-sqr(mt)/z/(1.-z));
kernal(0,0,0) = mt/sqrt(z*(1.-z));
kernal(2,1,1) = kernal(0,0,0);
kernal(0,0,1) = -z*root*exp(-ii*phi);
kernal(2,1,0) = -conj(kernal(0,0,1));
kernal(0,1,0) = (1.-z)*exp(-ii*phi)*root;
kernal(2,0,1) = -conj(kernal(0,1,0));
kernal(0,1,1) = 0.;
kernal(2,0,0) = 0.;
return kernal;
}

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