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diff --git a/Hadronization/SpinHadronizer.cc b/Hadronization/SpinHadronizer.cc
--- a/Hadronization/SpinHadronizer.cc
+++ b/Hadronization/SpinHadronizer.cc
@@ -1,306 +1,301 @@
// -*- C++ -*-
//
// This is the implementation of the non-inlined, non-templated member
// functions of the SpinHadronizer class.
//
#include "SpinHadronizer.h"
#include "ThePEG/Interface/ClassDocumentation.h"
#include "ThePEG/Interface/Parameter.h"
#include "ThePEG/Interface/Switch.h"
#include "ThePEG/EventRecord/Particle.h"
#include "ThePEG/Repository/UseRandom.h"
#include "ThePEG/Repository/EventGenerator.h"
#include "ThePEG/Utilities/DescribeClass.h"
#include "ThePEG/PDT/StandardMatchers.h"
#include "Herwig/Utilities/EnumParticles.h"
#include "ThePEG/Persistency/PersistentOStream.h"
#include "ThePEG/Persistency/PersistentIStream.h"
#include "ThePEG/Helicity/WaveFunction/SpinorWaveFunction.h"
#include "ThePEG/Helicity/WaveFunction/RSSpinorWaveFunction.h"
#include "ThePEG/Helicity/WaveFunction/VectorWaveFunction.h"
#include "ThePEG/Helicity/WaveFunction/ScalarWaveFunction.h"
#include "ThePEG/Helicity/WaveFunction/TensorWaveFunction.h"
#include "Cluster.h"
using namespace Herwig;
// choose only baryons
void SpinHadronizer::
handle(EventHandler &, const tPVector & tagged,const Hint & ) {
for(const tPPtr & hadron : tagged) {
// mesons
if(MesonMatcher::Check(hadron->data())) {
mesonSpin(hadron);
}
// baryons
else if(BaryonMatcher::Check(hadron->data())) {
baryonSpin(hadron);
}
else
continue;
}
}
void SpinHadronizer::baryonSpin(tPPtr baryon) {
// check only one parent
if(baryon->parents().size()!=1) return;
tPPtr parent = baryon->parents()[0];
// and its a cluster
if(parent->id()!=ParticleID::Cluster) return;
tClusterPtr cluster = dynamic_ptr_cast<tClusterPtr>(parent);
unsigned int prim_quark = (abs(baryon->id())/1000)%10;
int sign_quark = baryon->id()>0 ? prim_quark : -prim_quark;
// only strange, charm and bottom for the moment
if(prim_quark<minFlav_ || prim_quark>maxFlav_ ) return;
tPPtr quark;
for(unsigned int ix=0;ix<cluster->numComponents();++ix) {
if(cluster->particle(ix)->id()==sign_quark) {
quark = cluster->particle(ix);
}
}
if(!quark) return;
if(!quark->spinInfo()) return;
tcFermionSpinPtr sp(dynamic_ptr_cast<tcFermionSpinPtr>(quark->spinInfo()));
// decay it
sp->decay();
// create the spin info
if(baryon->dataPtr()->iSpin()==PDT::Spin1Half) {
vector<SpinorWaveFunction> waves;
RhoDMatrix rho;
SpinorWaveFunction::calculateWaveFunctions(waves,rho,baryon,baryon->id() >0 ? incoming : outgoing);
SpinorWaveFunction::constructSpinInfo(waves,baryon,outgoing,true);
}
else if(baryon->dataPtr()->iSpin()==PDT::Spin3Half) {
vector<RSSpinorWaveFunction> waves;
RhoDMatrix rho;
RSSpinorWaveFunction::calculateWaveFunctions(waves,rho,baryon,baryon->id() >0 ? incoming : outgoing);
RSSpinorWaveFunction::constructSpinInfo(waves,baryon,outgoing,true);
}
// can't handle spin > 3/2
else {
return;
}
// extract the polarization of the quark
double pol = 2.*sp->rhoMatrix()(1,1).real()-1.;
if(sign_quark<0) {
qPol_[prim_quark-3].first += pol;
qPol_[prim_quark-3].second += 1.;
}
else {
qPol_[prim_quark].first += pol;
qPol_[prim_quark].second += 1.;
}
// the different options for different spin types
const int mult = prim_quark*1000;
int bid = abs(baryon->id());
// lambda and Xi spin 1/2 (spin0 diquark)
if(bid== mult+122|| bid== mult+132|| bid== mult+232) {
baryon->spinInfo()->rhoMatrix()(0,0) = 0.5*(1.-pol);
baryon->spinInfo()->rhoMatrix()(1,1) = 0.5*(1.+pol);
}
// sigma_b, xi' and omega_b spin 1/2 (spin1 diquark)
else if(bid== mult+112|| bid== mult+212|| bid== mult+222||
bid== mult+312|| bid== mult+322|| bid== mult+332) {
baryon->spinInfo()->rhoMatrix()(0,0) = 0.5*(1.-pol) +pol*omegaHalf_;
baryon->spinInfo()->rhoMatrix()(1,1) = 0.5*(1.+pol) -pol*omegaHalf_;
}
// sigma*, xi* and omegab* spin 3/2 (spin1 diquark)
else if(bid== mult+114|| bid== mult+214|| bid== mult+224|| bid== mult+334) {
baryon->spinInfo()->rhoMatrix()(0,0) = 0.375*(1.-pol)*omegaHalf_;
baryon->spinInfo()->rhoMatrix()(1,1) = 0.5*(1.-pol)-omegaHalf_/8.*(3.-5.*pol);
baryon->spinInfo()->rhoMatrix()(2,2) = 0.5*(1.+pol)-omegaHalf_/8.*(3.+5.*pol);
baryon->spinInfo()->rhoMatrix()(3,3) = 0.375*(1.+pol)*omegaHalf_;
}
else
return;
// generator()->log() << "Baryon: " << *baryon << "\n";
// generator()->log() << "Parent: " << *cluster << "\n";
// generator()->log() << "Quark: " << *quark << "\n";
// generator()->log() << "Rho\n" << sp->rhoMatrix() << "\n";
// generator()->log() << "testing is decayed " << sp->decayed() <<" \n";
// generator()->log() << baryon->spinInfo()->rhoMatrix() << "\n";
}
void SpinHadronizer::mesonSpin(tPPtr meson) {
// check only one parent
if(meson->parents().size()!=1) return;
tPPtr parent = meson->parents()[0];
// and its a cluster
if(parent->id()!=ParticleID::Cluster) return;
tClusterPtr cluster = dynamic_ptr_cast<tClusterPtr>(parent);
unsigned int prim_quark = (abs(meson->id())/100)%10;
// find the quark id
int sign_quark = meson->id()>0 ? prim_quark : -prim_quark;
// B and K mesons have antiquarks bbar,sbar in mesons and quarks, b,s, in antimesons
if(prim_quark%2==1) sign_quark *= -1.;
// only strange, charm and bottom for the moment
if(prim_quark<minFlav_ || prim_quark>maxFlav_ ) return;
tPPtr quark;
for(unsigned int ix=0;ix<cluster->numComponents();++ix) {
if(cluster->particle(ix)->id()==sign_quark) {
quark = cluster->particle(ix);
}
}
if(!quark) return;
if(!quark->spinInfo()) return;
tcFermionSpinPtr sp(dynamic_ptr_cast<tcFermionSpinPtr>(quark->spinInfo()));
// decay it
sp->decay();
// create the spin info
if(meson->dataPtr()->iSpin()==PDT::Spin0) {
RhoDMatrix rho;
ScalarWaveFunction::calculateWaveFunctions(rho,meson,meson->id() > 0 ? incoming : outgoing);
ScalarWaveFunction::constructSpinInfo(meson,outgoing,true);
}
else if(meson->dataPtr()->iSpin()==PDT::Spin1) {
vector<VectorWaveFunction> waves;
RhoDMatrix rho;
- VectorWaveFunction::calculateWaveFunctions(waves,rho,meson,meson->id() > 0 ? incoming : outgoing,true);
- VectorWaveFunction::constructSpinInfo(waves,meson,outgoing,true,true);
+ VectorWaveFunction::calculateWaveFunctions(waves,rho,meson,meson->id() > 0 ? incoming : outgoing,false);
+ VectorWaveFunction::constructSpinInfo(waves,meson,outgoing,true,false);
}
else if(meson->dataPtr()->iSpin()==PDT::Spin2) {
vector<TensorWaveFunction> waves;
RhoDMatrix rho;
- TensorWaveFunction::calculateWaveFunctions(waves,rho,meson,meson->id() > 0 ? incoming : outgoing,true);
- TensorWaveFunction::constructSpinInfo(waves,meson,outgoing,true,true);
+ TensorWaveFunction::calculateWaveFunctions(waves,rho,meson,meson->id() > 0 ? incoming : outgoing,false);
+ TensorWaveFunction::constructSpinInfo(waves,meson,outgoing,true,false);
}
else {
return;
}
// extract the polarization of the quark
double pol = 2.*sp->rhoMatrix()(1,1).real()-1.;
if(sign_quark<0) {
qPol_[prim_quark-3].first += pol;
qPol_[prim_quark-3].second += 1.;
}
else {
qPol_[prim_quark].first += pol;
qPol_[prim_quark].second += 1.;
}
// the different options for different spin types
- int bid = abs(meson->id())%1000;
+ int bid = abs(meson->id());
// light-quark spin 1/2+ -> spin 0 heavy meson
- if(bid==311 || bid==321 || bid==331 || bid==411 || bid==421 || bid==431
- || bid==511 || bid==521 || bid==531) {
- return;
- }
- // light-quark spin 1/2+
- else if(bid==313 || bid==323 || bid==333 || bid==413 || bid==423 || bid==433
- || bid==513 || bid==523 || bid==533) {
+ if(bid==10313 || bid==10323 || bid==10333 || bid==10413 || bid==10423 || bid==10433
+ || bid==10513 || bid==10523 || bid==10533) {
// Falk-Peskin "no-win" theorem for non-excited heavy mesons:
// no polarization information would be find in the non-excited meson
// for the excted mesons
meson->spinInfo()->rhoMatrix()(0,0) = (1.-pol)/16. + (omegaThreeHalf_/16.)*(3.-5.*pol);
meson->spinInfo()->rhoMatrix()(1,1) = 0.25*(1.-omegaThreeHalf_);
meson->spinInfo()->rhoMatrix()(2,2) = (1.+pol)/16. + (omegaThreeHalf_/16.)*(3.+5.*pol);
}
// light-quark spin 3/2+ -> exited spin 2 meson
else if(bid==315 || bid==325 || bid==335 || bid==415 || bid==425 || bid==435
|| bid==515 || bid==525 || bid==535) {
meson->spinInfo()->rhoMatrix()(0,0) = 0.25*(1.-pol)*omegaThreeHalf_;
meson->spinInfo()->rhoMatrix()(1,1) = 0.1875*(1.-pol)-0.125*(1.-pol)*omegaThreeHalf_;
meson->spinInfo()->rhoMatrix()(2,2) = 0.25*(1.-omegaThreeHalf_);
meson->spinInfo()->rhoMatrix()(3,3) = 0.1875*(1.+pol)-0.125*(1.+pol)*omegaThreeHalf_;
meson->spinInfo()->rhoMatrix()(4,4) = 0.25*(1.+pol)*omegaThreeHalf_;
}
else {
return;
}
}
IBPtr SpinHadronizer::clone() const {
return new_ptr(*this);
}
IBPtr SpinHadronizer::fullclone() const {
return new_ptr(*this);
}
void SpinHadronizer::persistentOutput(PersistentOStream & os) const {
os << omegaHalf_ << omegaThreeHalf_;
}
void SpinHadronizer::persistentInput(PersistentIStream & is, int) {
is >> omegaHalf_ >> omegaThreeHalf_;
}
// The following static variable is needed for the type
// description system in ThePEG.
DescribeClass<SpinHadronizer,StepHandler>
describeHerwigSpinHadronizer("Herwig::SpinHadronizer", "Herwig.so");
void SpinHadronizer::Init() {
static ClassDocumentation<SpinHadronizer> documentation
("The SpinHadronizer class implements a simple mode for"
" the transfer of spin from quarks to hadrons");
static Parameter<SpinHadronizer,double> interfaceOmegaHalf
("OmegaHalf",
"The omega_1/2 Falk-Peskin parameter",
&SpinHadronizer::omegaHalf_, 2./3., 0.0, 1.0,
false, false, Interface::limited);
static Parameter<SpinHadronizer,double> interfaceOmegaThreeHalf
("OmegaThreeHalf",
"The omega_3/2 Falk-Peskin parameter",
&SpinHadronizer::omegaThreeHalf_, 0.2, 0.0, 1.0,
false, false, Interface::limited);
static Parameter<SpinHadronizer,unsigned int> interfaceMinimumFlavour
("MinimumFlavour",
"The minimum flavour of quark for which to transfer the polarization",
&SpinHadronizer::minFlav_, 3, 3, 5,
false, false, Interface::limited);
static Parameter<SpinHadronizer,unsigned int> interfaceMaximumFlavour
("MaximumFlavour",
"The maximum flavour of quark for which to transfer the polarization",
&SpinHadronizer::maxFlav_, 5, 3, 5,
false, false, Interface::limited);
static Switch<SpinHadronizer,bool> interfaceDebug
("Debug",
"Output info on polarizations each for debugging",
&SpinHadronizer::debug_, false, false, false);
static SwitchOption interfaceDebugYes
(interfaceDebug,
"Yes",
"Debug",
true);
static SwitchOption interfaceDebugNo
(interfaceDebug,
"No",
"No info",
false);
}
void SpinHadronizer::doinit() {
StepHandler::doinit();
if(minFlav_>maxFlav_)
throw InitException() << "The minimum flavour " << minFlav_
<< "must be lower the than maximum flavour " << maxFlav_
<< " in SpinHadronizer::doinit() "
<< Exception::runerror;
}
void SpinHadronizer::dofinish() {
StepHandler::dofinish();
if(debug_) {
for(unsigned int ix=0;ix<3;++ix) {
if(qPol_[ix].second!=0)
generator()->log() << "Average polarization of " << getParticleData(long(3+ix))->PDGName() << " antiquarks "
<< qPol_[ix].first/qPol_[ix].second << "\n";
if(qPol_[ix+3].second!=0)
generator()->log() << "Average polarization of " << getParticleData(long(3+ix))->PDGName() << " quarks "
<< qPol_[ix+3].first/qPol_[ix+3].second << "\n";
}
}
}
void SpinHadronizer::doinitrun() {
StepHandler::doinitrun();
}

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