G4GammaParticipants.cc

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#include "globals.hh"
#include "G4GammaParticipants.hh"
#include "G4LorentzVector.hh"
#include "G4V3DNucleus.hh"
#include <utility>

// Class G4GammaParticipants 

//#define debugGammaParticipants

G4VSplitableHadron* G4GammaParticipants::SelectInteractions(const G4ReactionProduct  &thePrimary) 
{
  // Check reaction threshold  - goes to CheckThreshold

  theProjectileSplitable = new G4QGSMSplitableHadron(thePrimary, TRUE);
        theProjectileSplitable->SetStatus(1);

  G4LorentzVector aPrimaryMomentum(thePrimary.GetMomentum(), thePrimary.GetTotalEnergy());
  G4LorentzVector aTargetNMomentum(0.,0.,0.,938.);
  if((!(aPrimaryMomentum.e()>-1)) && (!(aPrimaryMomentum.e()<1)) )
  {
    throw G4HadronicException(__FILE__, __LINE__,
        "G4GammaParticipants::SelectInteractions: primary nan energy.");
  }
  G4double S = (aPrimaryMomentum + aTargetNMomentum).mag2();
  G4double ThresholdMass = thePrimary.GetMass() + 938.;
  ModelMode = SOFT;

  #ifdef debugGammaParticipants
    G4cout <<G4endl<< "Gamma Participants - SelectInteractions " << G4endl;
                G4cout << "Energy and Nucleus Mass N "<<thePrimary.GetTotalEnergy()<<" "<<theNucleus->GetMassNumber()<<G4endl;
    G4cout << "SqrtS ThresholdMass ModelMode " <<std::sqrt(S)<<" "<<ThresholdMass<<" "<<ModelMode<< G4endl;
                G4cout << "ThresholdParameter QGSMThreshold "<<ThresholdParameter<<" "<<QGSMThreshold<<G4endl;
  #endif


  if (sqr(ThresholdMass + ThresholdParameter) > S)
  {
    ModelMode = DIFFRACTIVE;
  }

  if (sqr(ThresholdMass + QGSMThreshold) > S)
  {
    ModelMode = DIFFRACTIVE;
  }

  #ifdef debugGammaParticipants
    G4cout << "Interaction type (ModelMode) 0 - SOFT, 1 - DIFFRACTIVE:    "<<ModelMode<< G4endl;
  #endif

  std::for_each(theInteractions.begin(), theInteractions.end(), DeleteInteractionContent());
  theInteractions.clear();
  G4int totalCuts = 0;

//  #ifdef debug_G4GammaParticipants
//    G4double eK = thePrimary.GetKineticEnergy()/GeV;
//    G4int nucleonCount = theNucleus->GetMassNumber();
//  #endif

  G4int theCurrent = G4int(theNucleus->GetMassNumber()*G4UniformRand());
        G4int NucleonNo=0;

        theNucleus->StartLoop();
        G4Nucleon * pNucleon =0;

        while( (pNucleon = theNucleus->GetNextNucleon()) ) {if(NucleonNo == theCurrent) break; NucleonNo++;} 

        if ( pNucleon ) {

    G4QGSMSplitableHadron* aTarget = new G4QGSMSplitableHadron(*pNucleon);
          pNucleon->Hit(aTarget);

    if( (0.06 > G4UniformRand() &&(ModelMode==SOFT)) || (ModelMode==DIFFRACTIVE ) ) //  (false) //
    {     // Diffractive interaction
          G4InteractionContent * aInteraction = new G4InteractionContent(theProjectileSplitable);
          theProjectileSplitable->SetStatus(1*theProjectileSplitable->GetStatus());

          aInteraction->SetTarget(aTarget);
          aInteraction->SetTargetNucleon(pNucleon);
          aTarget->SetCollisionCount(0);
          aTarget->SetStatus(1);                             // Mark that is Diffr. interaction

          aInteraction->SetNumberOfDiffractiveCollisions(1);
          aInteraction->SetNumberOfSoftCollisions(0);
          aInteraction->SetStatus(1);

          theInteractions.push_back(aInteraction);
    totalCuts += 1;
    }
    else
    {
    // nondiffractive soft interaction occurs
    aTarget->IncrementCollisionCount(1);
          aTarget->SetStatus(0);
          theTargets.push_back(aTarget);

    theProjectileSplitable->IncrementCollisionCount(1);
          theProjectileSplitable->SetStatus(0*theProjectileSplitable->GetStatus());

    G4InteractionContent * aInteraction = 
                                           new G4InteractionContent(theProjectileSplitable);
    aInteraction->SetTarget(aTarget);
          aInteraction->SetTargetNucleon(pNucleon);
    aInteraction->SetNumberOfSoftCollisions(1);
          aInteraction->SetStatus(0);                        // Mark that is non-Diffr. interaction
    theInteractions.push_back(aInteraction);
    totalCuts += 1;
    }
        }
  return theProjectileSplitable;
}