G4XMesonBaryonElastic.cc

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#include "globals.hh"
#include "G4ios.hh"
#include "G4XMesonBaryonElastic.hh"
#include "G4KineticTrack.hh"
#include "G4Gamma.hh"
#include "G4PionPlus.hh"
#include "G4Proton.hh"
#include "G4XAqmElastic.hh"
#include "G4XPDGElastic.hh"

G4XMesonBaryonElastic::G4XMesonBaryonElastic()
{ 
  // As a first approximation the model is assumed to be valid over 
  // the entire energy range
  lowLimit = 0.;
  highLimit = DBL_MAX;
}


G4XMesonBaryonElastic::~G4XMesonBaryonElastic()
{ }


G4bool G4XMesonBaryonElastic::operator==(const G4XMesonBaryonElastic &right) const
{
  return (this == (G4XMesonBaryonElastic *) &right);
}


G4bool G4XMesonBaryonElastic::operator!=(const G4XMesonBaryonElastic &right) const
{
  return (this != (G4XMesonBaryonElastic *) &right);
}


G4double G4XMesonBaryonElastic::CrossSection(const G4KineticTrack& trk1, const G4KineticTrack& trk2) const
{
  G4double sigma;

  // No gamma-baryon elastic scattering 
  const G4ParticleDefinition* defLight = FindLightParticle(trk1,trk2);
  if (defLight == G4Gamma::GammaDefinition())
    {
      sigma = 0;
    }
  else
    {

      G4LorentzVector p41 = trk1.Get4Momentum();
      G4ThreeVector p3 = trk1.GetPosition();
      G4ParticleDefinition* def = G4PionPlus::PionPlusDefinition();

      G4KineticTrack piTrk(def,
                           trk1.GetFormationTime(),
                           p3,
                           (G4LorentzVector&)p41);

      G4LorentzVector p42 = trk2.Get4Momentum();    
      G4KineticTrack pTrk(((G4ParticleDefinition*)G4Proton::ProtonDefinition()),
                          trk2.GetFormationTime(),
                          (G4ThreeVector)trk2.GetPosition(),
                          (G4LorentzVector&)p42);
      
      G4XAqmElastic aqm;
      G4double xAqmDummy = aqm.CrossSection(piTrk,pTrk);
      G4double xAqm = aqm.CrossSection(trk1,trk2);
      G4double factor = 1.;
      if (xAqmDummy != 0.0)
        {
          factor = xAqm / xAqmDummy;
        }
      G4XPDGElastic pdg;
      
      sigma = pdg.CrossSection(piTrk,pTrk);
      sigma = sigma * factor;
    }
  
  return sigma;
}


G4String G4XMesonBaryonElastic::Name() const
{
  G4String name("MesonBaryonElasticCrossSection");
  return name;
}



G4bool G4XMesonBaryonElastic::IsValid(G4double e) const
{
  G4bool answer = InLimits(e,lowLimit,highLimit);

  return answer;
}