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diff --git a/Decay/HeavyMeson/HQETStrongDecayer.cc b/Decay/HeavyMeson/HQETStrongDecayer.cc
--- a/Decay/HeavyMeson/HQETStrongDecayer.cc
+++ b/Decay/HeavyMeson/HQETStrongDecayer.cc
@@ -1,364 +1,350 @@
// -*- C++ -*-
//
// This is the implementation of the non-inlined, non-templated member
// functions of the HQETStrongDecayer class.
//
#include "HQETStrongDecayer.h"
#include "ThePEG/Interface/ClassDocumentation.h"
#include "ThePEG/Interface/ParVector.h"
#include "ThePEG/EventRecord/Particle.h"
#include "ThePEG/Utilities/DescribeClass.h"
#include "ThePEG/Persistency/PersistentOStream.h"
#include "ThePEG/Persistency/PersistentIStream.h"
#include "ThePEG/Helicity/WaveFunction/TensorWaveFunction.h"
#include "ThePEG/Helicity/WaveFunction/VectorWaveFunction.h"
#include "ThePEG/Helicity/WaveFunction/ScalarWaveFunction.h"
#include "Herwig/Decay/TwoBodyDecayMatrixElement.h"
#include "Herwig/Utilities/Kinematics.h"
#include "ThePEG/Helicity/epsilon.h"
#include "ThePEG/Helicity/HelicityFunctions.h"
using namespace Herwig;
HQETStrongDecayer::HQETStrongDecayer()
: fPi_(130.2*MeV), g_(0.565), h_(0.565), deltaEta_(1./43.7), Lambda_(1.*GeV),
incoming_ ({413,413,423,433, //D* decay modes [0-3], VtoSS
415,415,425,425,435,435, //D*_2 decay modes [4-9], TtoSS
435,435,415,415,425,425,435,435}), //D*_2 decay modes [10-17], TtoVS
outgoingH_({421,411,421,431,
411,421,411,421,411,421,
413,423,413,423,413,423,413,423}),
outgoingL_({211,111,111,111,
111,211,-211,111,311,321,
311,321,111,211,-211,111,311,321}),
type_ ({1, 1, 1, -1,
2, 2, 2, 2, 2, 2,
3, 3, 3, 3, 3, 3, 3, 3}),
maxWeight_({1., 1., 1., 1.,
1., 1., 1., 1., 1., 1., 1., 1.,
1., 1., 1., 1., 1., 1.})
{}
void HQETStrongDecayer::doinit() {
DecayIntegrator::doinit();
// check consistence of the parameters
unsigned int isize=incoming_.size();
if(isize!=outgoingH_.size()||isize!=outgoingL_.size()||
isize!=maxWeight_.size()||isize!=type_ .size())
throw InitException() << "Inconsistent parameters in HQETStrongDecayer"
<< Exception::abortnow;
// set up the integration channels
PhaseSpaceModePtr mode;
for(unsigned int ix=0;ix<incoming_.size();++ix) {
tPDPtr in = getParticleData(incoming_[ix]);
tPDVector out = {getParticleData(outgoingH_[ix]),
getParticleData(outgoingL_[ix])};
if(in&&out[0]&&out[1])
mode=new_ptr(PhaseSpaceMode(in,out,maxWeight_[ix]));
else
mode=PhaseSpaceModePtr();
addMode(mode);
}
}
void HQETStrongDecayer::doinitrun() {
DecayIntegrator::doinitrun();
if(initialize()) {
for(unsigned int ix=0;ix<incoming_.size();++ix)
if(mode(ix)) maxWeight_[ix] = mode(ix)->maxWeight();
}
}
IBPtr HQETStrongDecayer::clone() const {
return new_ptr(*this);
}
IBPtr HQETStrongDecayer::fullclone() const {
return new_ptr(*this);
}
void HQETStrongDecayer::persistentOutput(PersistentOStream & os) const {
os << ounit(fPi_,MeV) << g_ << h_ << deltaEta_ << ounit(Lambda_,GeV) << maxWeight_;
}
void HQETStrongDecayer::persistentInput(PersistentIStream & is, int) {
is >> iunit(fPi_,MeV) >> g_ >> h_ >> deltaEta_ >> iunit(Lambda_,GeV) >> maxWeight_;
}
// The following static variable is needed for the type
// description system in ThePEG.
DescribeClass<HQETStrongDecayer,DecayIntegrator>
describeHerwigHQETStrongDecayer("Herwig::HQETStrongDecayer", "HwHMDecay.so");
void HQETStrongDecayer::Init() {
static ClassDocumentation<HQETStrongDecayer> documentation
("The HQETStrongDecayer class performs the strong decays of excited heavy mesons using HQET results.");
static Parameter<HQETStrongDecayer,Energy> interfacefPi
("fPi",
"The pion decay constant",
&HQETStrongDecayer::fPi_, MeV, 130.2*MeV, 100.0*MeV, 200.0*MeV,
false, false, Interface::limited);
static Parameter<HQETStrongDecayer,double> interfaceg
("g",
"The coupling for 1- to 0- decays",
&HQETStrongDecayer::g_, 0.565, 0.0, 1.0,
false, false, Interface::limited);
static Parameter<HQETStrongDecayer,double> interfaceh
("h",
"The coupling for D*_2 and D*_2s decays",
&HQETStrongDecayer::h_, 0.565, 0.0, 1.0,
false, false, Interface::limited);
static ParVector<HQETStrongDecayer,double> interfaceMaxWeight
("MaxWeight",
"The maximum weight for the decay mode",
&HQETStrongDecayer::maxWeight_,
0, 0, 0, 0., 100000., false, false, true);
static Parameter<HQETStrongDecayer,double> interfaceDeltaEta
("DeltaEta",
"The mixing parameter for eta-pi0 of isospin violating decays",
&HQETStrongDecayer::deltaEta_, 1./43.7, 0.0, 1.,
false, false, Interface::limited);
static Parameter<HQETStrongDecayer,Energy> interfacefLambda
("Lambda",
"D*_2 and D*_2s strong decays momentum scale",
&HQETStrongDecayer::Lambda_, GeV, 1.*GeV, .1*GeV, 2.*GeV,
false, false, Interface::limited);
}
int HQETStrongDecayer::modeNumber(bool & cc,tcPDPtr parent,
const tPDVector & children) const {
if(children.size()!=2) return -1;
int id(parent->id());
int idbar = parent->CC() ? parent->CC()->id() : id;
int id1(children[0]->id());
int id1bar = children[0]->CC() ? children[0]->CC()->id() : id1;
int id2(children[1]->id());
int id2bar = children[1]->CC() ? children[1]->CC()->id() : id2;
int imode(-1);
unsigned int ix(0);
cc=false;
do {
if(id ==incoming_[ix]) {
if((id1 ==outgoingH_[ix]&&id2 ==outgoingL_[ix])||
(id2 ==outgoingH_[ix]&&id1 ==outgoingL_[ix])) imode=ix;
}
if(idbar==incoming_[ix]) {
if((id1bar==outgoingH_[ix]&&id2bar==outgoingL_[ix])||
(id2bar==outgoingH_[ix]&&id1bar==outgoingL_[ix])) {
imode=ix;
cc=true;
}
}
++ix;
}
while(ix<incoming_.size()&&imode<0);
return imode;
}
void HQETStrongDecayer::
constructSpinInfo(const Particle & part, ParticleVector decay) const {
switch (part.dataPtr()->iSpin()) {
case PDT::Spin1:
Helicity::VectorWaveFunction::constructSpinInfo(vecIn_,const_ptr_cast<tPPtr>(&part),
Helicity::incoming,true,false);
break;
case PDT::Spin2:
Helicity::TensorWaveFunction::constructSpinInfo(tensorIn_,const_ptr_cast<tPPtr>(&part),
Helicity::incoming,true,false);
break;
default:
assert(false);
}
// set up the spin information for the decay products
for(unsigned int ix=0;ix<decay.size();++ix) {
switch (decay[ix]->dataPtr()->iSpin()) {
case PDT::Spin1:
Helicity::VectorWaveFunction::constructSpinInfo(vecOut_,decay[ix],
Helicity::outgoing,true,false);
break;
case PDT::Spin0:
Helicity::ScalarWaveFunction::constructSpinInfo(decay[ix],Helicity::outgoing,true);
break;
default:
assert(false);
}
}
}
// matrix elememt for the process
double HQETStrongDecayer::me2(const int, const Particle & part,
const tPDVector & outgoing,
const vector<Lorentz5Momentum> & momenta,
MEOption meopt) const {
if(!ME()) {
if(abs(type_[imode()])==1) {
ME(new_ptr(TwoBodyDecayMatrixElement(PDT::Spin1,PDT::Spin0,PDT::Spin0)));
}
if(abs(type_[imode()])==2) {
ME(new_ptr(TwoBodyDecayMatrixElement(PDT::Spin2,PDT::Spin0,PDT::Spin0)));
}
if(abs(type_[imode()])==3) {
ME(new_ptr(TwoBodyDecayMatrixElement(PDT::Spin2,PDT::Spin1,PDT::Spin0)));
}
}
// stuff for incoming particle
if(meopt==Initialize) {
if(abs(type_[imode()])==1) {
rho_ = RhoDMatrix(PDT::Spin1);
Helicity::VectorWaveFunction::calculateWaveFunctions(vecIn_,rho_,const_ptr_cast<tPPtr>(&part),
Helicity::incoming,false);
}
else if(abs(type_[imode()])==2 || abs(type_[imode()])==3) {
rho_ = RhoDMatrix(PDT::Spin2);
Helicity::TensorWaveFunction::calculateWaveFunctions(tensorIn_,rho_,const_ptr_cast<tPPtr>(&part),
Helicity::incoming,false);
}
else {
cerr << part << "\n";
cerr << "testing " << imode() << " " << type_[imode()] << "\n";
assert(false);
}
}
double output(0.);
// calculate the matrix element
InvEnergy fact;
Energy pcm = Kinematics::pstarTwoBodyDecay(part.mass(),momenta[0].mass(),
momenta[1].mass()); //test subject
double test(0.), ratio(0.);
// HeavyVectorMeson to PScalarMeson + PScalarMeson
if(abs(type_[imode()])==1) {
fact = -2.*g_/fPi_*sqrt(momenta[0].mass()/part.mass());
if(abs(outgoing[1]->id())==111) {
fact *= type_[imode()]>0 ? 0.5 : 0.125*deltaEta_*sqrt(0.5) ;
}
for(unsigned int ix=0;ix<3;++ix) {
(*ME())(ix,0,0) = fact*(vecIn_[ix]*momenta[1]);
}
// analytic test of the answer
test = 4.*sqr(g_)*momenta[0].mass()*sqr(pcm)/3./sqr(fPi_)/part.mass();
if(abs(outgoing[1]->id())==111) {
test *= type_[imode()]>0 ? 0.5 : 0.5*deltaEta_*sqrt(0.5) ;
}
}
// HeavyTensorMeson to PScalarMeson + PScalarMeson
else if(abs(type_[imode()])==2) {
fact = -2.*h_/fPi_*sqrt(momenta[0].mass()/part.mass());
- if(abs(outgoing[1]->id())==111) {
- fact *= sqrt(0.5); // ??
- }
for(unsigned int ix=0;ix<5;++ix) {
(*ME())(ix,0,0) = (fact/Lambda_)*((tensorIn_[ix]*momenta[1])*momenta[0]);
}
// analytic test of the answer
- test = 8.*sqr(h_)*momenta[0].mass()*sqr(sqr(pcm))/10./sqr(fPi_)/sqr(Lambda_)/part.mass();
- if(abs(outgoing[1]->id())==111) {
- test *= sqrt(0.5);
- }
+ test = 8.*sqr(h_)*momenta[0].mass()*sqr(sqr(pcm))/15./sqr(fPi_)/sqr(Lambda_)/part.mass();
}
// HeavyTensorMeson to VectorMeson + PScalarMeson
else if(abs(type_[imode()])==3) {
//get the polarization vectors
- vecOut_.resize(3);
vecOut_={
- HelicityFunctions::polarizationVector(momenta[0],0,Helicity::outgoing),
- HelicityFunctions::polarizationVector(momenta[0],1,Helicity::outgoing),
- HelicityFunctions::polarizationVector(momenta[0],2,Helicity::outgoing)};
+ HelicityFunctions::polarizationVector(-momenta[0],0,Helicity::outgoing),
+ HelicityFunctions::polarizationVector(-momenta[0],1,Helicity::outgoing),
+ HelicityFunctions::polarizationVector(-momenta[0],2,Helicity::outgoing)};
fact = -2.*h_/fPi_*sqrt(momenta[0].mass()/part.mass());
- if(abs(outgoing[1]->id())==111) {
- fact *= sqrt(0.5); // ??
- }
for(unsigned int ix=0;ix<5;++ix) {
for(unsigned int iy=0;iy<3;++iy) {
if(iy==1) (*ME())(ix,iy,0)=0.;
else{
LorentzVector<complex<InvEnergy> > vtemp =
- (fact/sqr(Lambda_))*epsilon(momenta[0],vecOut_[iy],momenta[1]); ///!!!
+ (fact/Lambda_/part.mass())*epsilon(momenta[0],vecOut_[iy],momenta[1]);
(*ME())(ix,iy,0) = (momenta[1]*tensorIn_[ix]).dot(vtemp);
}
}
}
// analytic test of the answer
- test = 4.*sqr(h_)*momenta[0].mass()*sqr(sqr(pcm))/5./sqr(fPi_)/sqr(Lambda_)/part.mass(); ///!!!
- if(abs(outgoing[1]->id())==111) {
- test *= sqrt(0.5);
- }
+ test = 4.*sqr(h_)*momenta[0].mass()*sqr(sqr(pcm))/5./sqr(fPi_)/sqr(Lambda_)/part.mass();
}
else {
assert(false);
}
output = ME()->contract(rho_).real();
//testing
ratio = (output-test)/(output+test);
generator()->log() << "testing matrix element for " << part.PDGName() << " -> "
- << outgoing[0]->PDGName() << " " << outgoing[1]->PDGName() << " "
- << output << " " << test << " " << ratio << endl;
-
+ << outgoing[0]->PDGName() << " " << outgoing[1]->PDGName() << " "
+ << output << " " << test << " " << ratio << endl;
// return the answer
return output;
}
bool HQETStrongDecayer::twoBodyMEcode(const DecayMode & dm,int & mecode,
double & coupling) const {
// int imode(-1);
// int id(dm.parent()->id());
// int idbar = dm.parent()->CC() ? dm.parent()->CC()->id() : id;
// ParticleMSet::const_iterator pit(dm.products().begin());
// int id1((**pit).id());
// int id1bar = (**pit).CC() ? (**pit).CC()->id() : id1;
// ++pit;
// int id2((**pit).id());
// int id2bar = (**pit).CC() ? (**pit).CC()->id() : id2;
// unsigned int ix(0); bool order(false);
// do {
// if(id ==incoming_[ix]) {
// if(id1==outgoingH_[ix]&&id2==outgoingL_[ix]) {
// imode=ix;
// order=true;
// }
// if(id2==outgoingH_[ix]&&id1==outgoingL_[ix]) {
// imode=ix;
// order=false;
// }
// }
// if(idbar==incoming_[ix]&&imode<0) {
// if(id1bar==outgoingH_[ix]&&id2bar==outgoingL_[ix]) {
// imode=ix;
// order=true;
// }
// if(id2bar==outgoingH_[ix]&&id1bar==outgoingL_[ix]) {
// imode=ix;
// order=false;
// }
// }
// ++ix;
// }
// while(ix<incoming_.size()&&imode<0);
// coupling=_coupling[imode]*dm.parent()->mass();
// mecode=7;
// return order;
}
void HQETStrongDecayer::dataBaseOutput(ofstream & output,
bool header) const {
if(header) output << "update decayers set parameters=\"";
// parameters for the DecayIntegrator base class
DecayIntegrator::dataBaseOutput(output,false);
// the rest of the parameters
// couplings
output << "newdef " << name() << ":fPi " << fPi_/MeV << "\n";
output << "newdef " << name() << ":g " << g_ << "\n";
if(header) output << "\n\" where BINARY ThePEGName=\""
<< fullName() << "\";" << endl;
for(unsigned int ix=0;ix<incoming_.size();++ix) {
output << "newdef " << name() << ":MaxWeight " << ix << " " << maxWeight_[ix] << "\n";
}
}

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