G4QGSModel.icc

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//****************************************************************************************************************
template<class ParticipantType>
G4QGSModel<ParticipantType>::G4QGSModel() 
    {
        G4VPartonStringModel::SetThisPointer(this);
        SetEnergyMomentumCheckLevels(2*CLHEP::perCent, 150*CLHEP::MeV);
    }
template<class ParticipantType>
G4QGSModel<ParticipantType>::G4QGSModel(const G4QGSModel &right)
    {
        G4VPartonStringModel::SetThisPointer(this);
        std::pair<G4double, G4double> levels=right.GetEnergyMomentumCheckLevels();
        SetEnergyMomentumCheckLevels(levels.first, levels.second);
    }

template<class ParticipantType>
G4QGSModel<ParticipantType>& G4QGSModel<ParticipantType>::operator=(const G4QGSModel &right)
    {
       if (this != &right )
       {
         G4VPartonStringModel::SetThisPointer(this);
         std::pair<G4double, G4double> levels=right.GetEnergyMomentumCheckLevels();
         SetEnergyMomentumCheckLevels(levels.first, levels.second);
      }
    }
template<class ParticipantType>
G4QGSModel<ParticipantType>::~G4QGSModel()
    {
    }

template<class ParticipantType>
void G4QGSModel<ParticipantType>::Init(const G4Nucleus & aNucleus, const G4DynamicParticle & aProjectile)
    {
     // clean-up and consistency with design, HPW Feb 1999
    theParticipants.Init(aNucleus.GetA_asInt(),aNucleus.GetZ_asInt());
    theCurrentVelocity.setX(0);    
    theCurrentVelocity.setY(0); 
     // HPW Feb 1999 
     // this is an approximation, neglecting the motion of nucleons in the nucleus & p,n mass differences. @@@
//    G4double vz_old = aProjectile.Get4Momentum().pz()/
//                  (aProjectile.Get4Momentum().e() + G4Proton::Proton()->GetPDGMass());
    G4double nCons = 1;
    if(std::abs(aProjectile.GetDefinition()->GetBaryonNumber()) !=0) 
    {
      nCons = std::abs(aProjectile.GetDefinition()->GetBaryonNumber());
    }
    G4double pz_per_projectile = aProjectile.Get4Momentum().pz()/nCons;
//    G4double e_per_projectile = aProjectile.Get4Momentum().vect()*aProjectile.Get4Momentum().vect();
//             e_per_projectile /=nCons*nCons;
//           e_per_projectile += G4Proton::Proton()->GetPDGMass()*G4Proton::Proton()->GetPDGMass();
    G4double e_per_projectile = aProjectile.Get4Momentum()*aProjectile.Get4Momentum();
             e_per_projectile += aProjectile.Get4Momentum().vect()*aProjectile.Get4Momentum().vect();
             e_per_projectile /=nCons*nCons;
             e_per_projectile = std::sqrt(e_per_projectile);
             e_per_projectile += G4Proton::Proton()->GetPDGMass();
    G4double vz = pz_per_projectile/e_per_projectile;
//--DEBUG--    G4cout << "IncomingMomentum - vz "<<aProjectile.Get4Momentum()<< ", " << vz <<G4endl;
    theCurrentVelocity.setZ(vz);
    theParticipants.DoLorentzBoost(-theCurrentVelocity); 
    G4LorentzVector Mom = aProjectile.Get4Momentum();
    Mom.boost(-theCurrentVelocity);
    G4ReactionProduct theProjectile;   
    theProjectile.SetDefinition(aProjectile.GetDefinition());
    theProjectile.SetTotalEnergy(Mom.e());
    theProjectile.SetMomentum(Mom.vect());
//--DEBUG--    G4cout << "PreInteractionMomentum "<<Mom<<G4endl;
    theParticipants.BuildInteractions(theProjectile);
    theParticipants.GetWoundedNucleus()->DoLorentzBoost(theCurrentVelocity);
    }

template<class ParticipantType>
G4ExcitedStringVector * G4QGSModel<ParticipantType>::GetStrings()
{
  // clean-up and consistancy with design, HPW Feb 1999
  // also fixing a memory leak, removing unnecessary caching, and 
  // streamlining of logic
  G4PartonPair* aPair;
  G4ExcitedStringVector* theStrings = new G4ExcitedStringVector;
  G4ExcitedString * aString;
  while( (aPair = theParticipants.GetNextPartonPair()) )
  {
    if (aPair->GetCollisionType() == G4PartonPair::DIFFRACTIVE)
    {
      aString = theDiffractiveStringBuilder.BuildString(aPair);
      // G4cout << "diffractive "<<aString->Get4Momentum()<<G4endl;
    }
    else
    {
      aString = theSoftStringBuilder.BuildString(aPair);
      // G4cout << "soft "<<aString->Get4Momentum()<<G4endl;
    }
//--DEBUG-- G4cout << " QGSModel.icc::GetStrings() theCurrentVelocity " << theCurrentVelocity << G4endl;   
    aString->Boost(theCurrentVelocity);  
    theStrings->push_back(aString);
    delete aPair;
  }
//--DEBUG--  G4cout << G4endl;
//  for(G4int i=0; i<theStrings->size(); i++)
//  {
//   G4cout << "String = "<<theStrings->operator[](i)->Get4Momentum()<<G4endl;
//  }
  return theStrings;
}

template<class ParticipantType>
G4V3DNucleus* G4QGSModel<ParticipantType>::GetWoundedNucleus() const
{
  return theParticipants.GetWoundedNucleus();
}

template<class ParticipantType>
void G4QGSModel<ParticipantType>::ModelDescription(std::ostream& outFile) const
{
  outFile << "The Quark-Gluon String (QGS) model simulates the interaction\n"
          << "of protons, neutrons, pions and kaons with nuclei in the\n"
          << "approximate energy range 20 GeV to 50 TeV. The model handles\n"
          << "the selection of collision partners, splitting of the nucleons\n"
          << "into quarks and di-quarks, the formation and excitation of\n"
          << "quark-gluon strings, string hadronization and diffractive dissociation.\n";
}
//********************************************************************************************************************* 

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