Files
geant4/source/processes/hadronic/models/parton_string/hadronization/src/G4ExcitedStringDecay.cc
T
2016-12-09 12:35:28 +01:00

357 lines
14 KiB
C++

//
// ********************************************************************
// * License and Disclaimer *
// * *
// * The Geant4 software is copyright of the Copyright Holders of *
// * the Geant4 Collaboration. It is provided under the terms and *
// * conditions of the Geant4 Software License, included in the file *
// * LICENSE and available at http://cern.ch/geant4/license . These *
// * include a list of copyright holders. *
// * *
// * Neither the authors of this software system, nor their employing *
// * institutes,nor the agencies providing financial support for this *
// * work make any representation or warranty, express or implied, *
// * regarding this software system or assume any liability for its *
// * use. Please see the license in the file LICENSE and URL above *
// * for the full disclaimer and the limitation of liability. *
// * *
// * This code implementation is the result of the scientific and *
// * technical work of the GEANT4 collaboration. *
// * By using, copying, modifying or distributing the software (or *
// * any work based on the software) you agree to acknowledge its *
// * use in resulting scientific publications, and indicate your *
// * acceptance of all terms of the Geant4 Software license. *
// ********************************************************************
//
// Historic fragment from M.Komogorov; clean-up still necessary @@@
#include "G4ExcitedStringDecay.hh"
#include "G4SystemOfUnits.hh"
#include "G4KineticTrack.hh"
//#define debug_G4ExcitedStringDecay
//#define debug_G4ExcitedStringCorr
G4ExcitedStringDecay::G4ExcitedStringDecay() : G4VStringFragmentation(),theStringDecay(0)
{}
G4ExcitedStringDecay::G4ExcitedStringDecay(G4VLongitudinalStringDecay * aStringDecay)
: G4VStringFragmentation(),
theStringDecay(aStringDecay)
{}
G4ExcitedStringDecay::G4ExcitedStringDecay(const G4ExcitedStringDecay &)
: G4VStringFragmentation(),
theStringDecay(0)
{
throw G4HadronicException(__FILE__, __LINE__, "G4ExcitedStringDecay::copy ctor not accessible");
}
G4ExcitedStringDecay::~G4ExcitedStringDecay()
{
}
const G4ExcitedStringDecay & G4ExcitedStringDecay::operator=(const G4ExcitedStringDecay &)
{
throw G4HadronicException(__FILE__, __LINE__, "G4ExcitedStringDecay::operator= meant to not be accessable");
return *this;
}
int G4ExcitedStringDecay::operator==(const G4ExcitedStringDecay &) const
{
return 0;
}
int G4ExcitedStringDecay::operator!=(const G4ExcitedStringDecay &) const
{
return 1;
}
G4KineticTrackVector *G4ExcitedStringDecay::FragmentString(const G4ExcitedString &theString)
{
if ( theStringDecay == NULL ) theStringDecay=new G4LundStringFragmentation();
return theStringDecay->FragmentString(theString);
}
G4KineticTrackVector *G4ExcitedStringDecay::FragmentStrings(const G4ExcitedStringVector * theStrings)
{
G4LorentzVector KTsum(0.,0.,0.,0.);
#ifdef debug_G4ExcitedStringDecay
G4cout<<G4endl;
G4cout<<"--------------------------- G4ExcitedStringDecay ----------------------"<<G4endl;
G4cout<<"Hadronization of Excited Strings: theStrings->size() "<<theStrings->size()<<G4endl;
#endif
for ( unsigned int astring=0; astring < theStrings->size(); astring++)
{
if ( theStrings->operator[](astring)->IsExcited() ) {
KTsum+= theStrings->operator[](astring)->Get4Momentum();
} else {
KTsum+=theStrings->operator[](astring)->GetKineticTrack()->Get4Momentum();
}
}
G4LorentzRotation toCms( -1 * KTsum.boostVector() );
G4LorentzRotation toLab(toCms.inverse());
G4LorentzVector Ptmp;
KTsum=G4LorentzVector(0.,0.,0.,0.);
for ( unsigned int astring=0; astring < theStrings->size(); astring++)
{
if ( theStrings->operator[](astring)->IsExcited() ) {
Ptmp=toCms * theStrings->operator[](astring)->GetLeftParton()->Get4Momentum();
theStrings->operator[](astring)->GetLeftParton()->Set4Momentum(Ptmp);
Ptmp=toCms * theStrings->operator[](astring)->GetRightParton()->Get4Momentum();
theStrings->operator[](astring)->GetRightParton()->Set4Momentum(Ptmp);
KTsum+= theStrings->operator[](astring)->Get4Momentum();
} else {
Ptmp=toCms * theStrings->operator[](astring)->GetKineticTrack()->Get4Momentum();
theStrings->operator[](astring)->GetKineticTrack()->Set4Momentum(Ptmp);
KTsum+= theStrings->operator[](astring)->GetKineticTrack()->Get4Momentum();
}
}
G4KineticTrackVector * theResult = new G4KineticTrackVector;
G4int attempts(0);
G4bool success=false;
G4bool NeedEnergyCorrector=false;
do {
#ifdef debug_G4ExcitedStringDecay
G4cout<<"New try No "<<attempts<<" to hadronize strings"<<G4endl;
#endif
std::for_each(theResult->begin() , theResult->end() , DeleteKineticTrack());
theResult->clear();
attempts++;
G4LorentzVector KTsecondaries(0.,0.,0.,0.);
NeedEnergyCorrector=false;
for ( unsigned int astring=0; astring < theStrings->size(); astring++)
{
#ifdef debug_G4ExcitedStringDecay
G4cout<<"String No "<<astring+1<<" Excited? "<<theStrings->operator[](astring)->IsExcited()<<G4endl;
G4cout<<"String No "<<astring+1<<" 4Momentum "<<theStrings->operator[](astring)->Get4Momentum()
<<" "<<theStrings->operator[](astring)->Get4Momentum().mag()<<G4endl;
#endif
G4KineticTrackVector * generatedKineticTracks = NULL;
if ( theStrings->operator[](astring)->IsExcited() )
{
#ifdef debug_G4ExcitedStringDecay
G4cout<<"Fragment String with partons: "
<<theStrings->operator[](astring)->GetLeftParton()->GetPDGcode() <<" "
<<theStrings->operator[](astring)->GetRightParton()->GetPDGcode()<<" "
<<"Direction "<<theStrings->operator[](astring)->GetDirection()<<G4endl;
#endif
generatedKineticTracks=FragmentString(*theStrings->operator[](astring));
#ifdef debug_G4ExcitedStringDecay
G4cout<<"(G4ExcitedStringDecay) Number of produced hadrons = "<<generatedKineticTracks->size()<<G4endl;
#endif
} else {
#ifdef debug_G4ExcitedStringDecay
G4cout<<" GetTrack from the String"<<G4endl;
#endif
G4LorentzVector Mom=theStrings->operator[](astring)->GetKineticTrack()->Get4Momentum();
G4KineticTrack * aTrack= new G4KineticTrack(
theStrings->operator[](astring)->GetKineticTrack()->GetDefinition(),
theStrings->operator[](astring)->GetKineticTrack()->GetFormationTime(),
G4ThreeVector(0), Mom);
aTrack->SetPosition(theStrings->operator[](astring)->GetKineticTrack()->GetPosition());
#ifdef debug_G4ExcitedStringDecay
G4cout<<" A particle stored in the track is "<<aTrack->GetDefinition()->GetParticleName()<<G4endl;
#endif
generatedKineticTracks = new G4KineticTrackVector;
generatedKineticTracks->push_back(aTrack);
}
//if (generatedKineticTracks == NULL)
if (generatedKineticTracks->size() == 0)
{
//G4cerr << "G4VPartonStringModel:No KineticTracks produced" << G4endl;
//continue;
success=false; NeedEnergyCorrector=false; break;
}
G4LorentzVector KTsum1(0.,0.,0.,0.);
for ( unsigned int aTrack=0; aTrack<generatedKineticTracks->size();aTrack++)
{
#ifdef debug_G4ExcitedStringDecay
G4cout<<"Prod part No. "<<aTrack+1<<" "
<<(*generatedKineticTracks)[aTrack]->GetDefinition()->GetParticleName()<<" "
<<(*generatedKineticTracks)[aTrack]->Get4Momentum()<<G4endl;
#endif
theResult->push_back(generatedKineticTracks->operator[](aTrack));
KTsum1+= (*generatedKineticTracks)[aTrack]->Get4Momentum();
}
KTsecondaries+=KTsum1;
#ifdef debug_G4ExcitedStringDecay
G4cout << "String secondaries(" <<generatedKineticTracks->size()<< ")"<<G4endl
<<"Init string momentum: "<< theStrings->operator[](astring)->Get4Momentum()<<G4endl
<<"Final hadrons momentum: "<< KTsum1 << G4endl;
#endif
if ( KTsum1.e() > 0 && std::abs((KTsum1.e()-theStrings->operator[](astring)->Get4Momentum().e()) / KTsum1.e()) > perMillion )
{
NeedEnergyCorrector=true;
}
#ifdef debug_G4ExcitedStringDecay
G4cout<<"NeedEnergyCorrection yes/no "<<NeedEnergyCorrector<<G4endl;
#endif
// clean up
delete generatedKineticTracks;
success=true;
}
//success=true;
if ( NeedEnergyCorrector ) success=EnergyAndMomentumCorrector(theResult, KTsum);
} while(!success && (attempts < 100)); /* Loop checking, 07.08.2015, A.Ribon */
for ( unsigned int aTrack=0; aTrack<theResult->size();aTrack++)
{
Ptmp=(*theResult)[aTrack]->Get4Momentum();
Ptmp.transform( toLab);
(*theResult)[aTrack]->Set4Momentum(Ptmp);
}
#ifdef debug_G4ExcitedStringDecay
G4cout<<"End of the strings fragmentation (G4ExcitedStringDecay)"<<G4endl;
G4LorentzVector KTsum1(0.,0.,0.,0.);
for ( unsigned int aTrack=0; aTrack<theResult->size();aTrack++)
{
G4cout << " corrected tracks .. " << (*theResult)[aTrack]->GetDefinition()->GetParticleName()
<<" " << (*theResult)[aTrack]->Get4Momentum()
<<" " << (*theResult)[aTrack]->Get4Momentum().mag()<< G4endl;
KTsum1+= (*theResult)[aTrack]->Get4Momentum();
}
G4cout << "Needcorrector/success " << NeedEnergyCorrector << "/" << success
<< ", Corrected total 4 momentum " << KTsum1 << G4endl;
if ( ! success ) G4cout << "failed to correct E/p" << G4endl;
G4cout<<"End of the Hadronization (G4ExcitedStringDecay)"<<G4endl;
#endif
for ( unsigned int astring=0; astring < theStrings->size(); astring++)
{
if ( theStrings->operator[](astring)->IsExcited() ) {
Ptmp=theStrings->operator[](astring)->GetLeftParton()->Get4Momentum();
Ptmp.transform( toLab);
theStrings->operator[](astring)->GetLeftParton()->Set4Momentum(Ptmp);
Ptmp=theStrings->operator[](astring)->GetRightParton()->Get4Momentum();
Ptmp.transform( toLab);
theStrings->operator[](astring)->GetRightParton()->Set4Momentum(Ptmp);
} else {
Ptmp=theStrings->operator[](astring)->GetKineticTrack()->Get4Momentum();
Ptmp.transform( toLab);
theStrings->operator[](astring)->GetKineticTrack()->Set4Momentum(Ptmp);
}
}
return theResult;
}
G4bool G4ExcitedStringDecay::EnergyAndMomentumCorrector
(G4KineticTrackVector* Output, G4LorentzVector& TotalCollisionMom)
{
const int nAttemptScale = 500;
const double ErrLimit = 1.E-5;
if (Output->empty()) return TRUE;
G4LorentzVector SumMom;
G4double SumMass = 0;
G4double TotalCollisionMass = TotalCollisionMom.m();
#ifdef debug_G4ExcitedStringCorr
G4cout<<G4endl<<"EnergyAndMomentumCorrector. Number of particles: "<<Output->size()<<G4endl;
#endif
// Calculate sum hadron 4-momenta and summing hadron mass
unsigned int cHadron;
for(cHadron = 0; cHadron < Output->size(); cHadron++)
{
SumMom += Output->operator[](cHadron)->Get4Momentum();
SumMass += Output->operator[](cHadron)->GetDefinition()->GetPDGMass();
}
#ifdef debug_G4ExcitedStringCorr
G4cout<<"Sum part mom "<<SumMom<<" "<<SumMom.mag()<<G4endl
<<"Sum str mom "<<TotalCollisionMom<<" "<<TotalCollisionMom.mag()<<G4endl;
G4cout<<"SumMass TotalCollisionMass "<<SumMass<<" "<<TotalCollisionMass<<G4endl;
#endif
// Cannot correct a single particle
if (Output->size() < 2) return FALSE;
if (SumMass > TotalCollisionMass) return FALSE;
SumMass = SumMom.m2();
if (SumMass < 0) return FALSE;
SumMass = std::sqrt(SumMass);
// Compute c.m.s. hadron velocity and boost KTV to hadron c.m.s.
//G4ThreeVector Beta = -SumMom.boostVector();
G4ThreeVector Beta = -TotalCollisionMom.boostVector();
Output->Boost(Beta);
// Scale total c.m.s. hadron energy (hadron system mass).
// It should be equal interaction mass
G4double Scale = 1;
G4int cAttempt = 0;
G4double Sum = 0;
G4bool success = false;
for(cAttempt = 0; cAttempt < nAttemptScale; cAttempt++)
{
Sum = 0;
for(cHadron = 0; cHadron < Output->size(); cHadron++)
{
G4LorentzVector HadronMom = Output->operator[](cHadron)->Get4Momentum();
HadronMom.setVect(Scale*HadronMom.vect());
G4double E = std::sqrt(HadronMom.vect().mag2() + sqr(Output->operator[](cHadron)->GetDefinition()->GetPDGMass()));
HadronMom.setE(E);
Output->operator[](cHadron)->Set4Momentum(HadronMom);
Sum += E;
}
Scale = TotalCollisionMass/Sum;
#ifdef debug_G4ExcitedStringCorr
G4cout << "Scale-1=" << Scale -1
<< ", TotalCollisionMass=" << TotalCollisionMass
<< ", Sum=" << Sum
<< G4endl;
#endif
if (std::fabs(Scale - 1) <= ErrLimit)
{
success = true;
break;
}
}
#ifdef debug_G4ExcitedStringCorr
if(!success)
{
G4cout << "G4ExcitedStringDecay::EnergyAndMomentumCorrector - Warning"<<G4endl;
G4cout << " Scale not unity at end of iteration loop: "<<TotalCollisionMass<<" "<<Sum<<" "<<Scale<<G4endl;
G4cout << " Number of secondaries: " << Output->size() << G4endl;
G4cout << " Wanted total energy: " << TotalCollisionMom.e() << G4endl;
G4cout << " Increase number of attempts or increase ERRLIMIT"<<G4endl;
//throw G4HadronicException(__FILE__, __LINE__, "G4ExcitedStringDecay failed to correct...");
}
#endif
// Compute c.m.s. interaction velocity and KTV back boost
Beta = TotalCollisionMom.boostVector();
Output->Boost(Beta);
return success;
}