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()) )  /* Loop checking, 26.10.2015, A.Ribon */
  {
    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>
G4V3DNucleus* G4QGSModel<ParticipantType>::GetProjectileNucleus() const
{
  return 0;
}

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";
}

//*********************************************************************************************************************