G4INCLNuclearPotentialIsospin.cc

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// INCL++ intra-nuclear cascade model
// Alain Boudard, CEA-Saclay, France
// Joseph Cugnon, University of Liege, Belgium
// Jean-Christophe David, CEA-Saclay, France
// Pekka Kaitaniemi, CEA-Saclay, France, and Helsinki Institute of Physics, Finland
// Sylvie Leray, CEA-Saclay, France
// Davide Mancusi, CEA-Saclay, France
//
#define INCLXX_IN_GEANT4_MODE 1
 
#include "globals.hh"
 
/** \file G4INCLNuclearPotentialIsospin.cc
 * \brief Isospin-dependent nuclear potential.
 *
 * Provides an isospin-dependent nuclear potential.
 *
 * \date 28 February 2011
 * \author Davide Mancusi
 */
 
#include "G4INCLNuclearPotentialIsospin.hh"
#include "G4INCLNuclearPotentialConstant.hh"
#include "G4INCLParticleTable.hh"
#include "G4INCLGlobals.hh"
 
namespace G4INCL {
 
  namespace NuclearPotential {
 
    // Constructors
    NuclearPotentialIsospin::NuclearPotentialIsospin(const G4int A, const G4int Z, const G4bool aPionPotential)
      : INuclearPotential(A, Z, aPionPotential)
    {
      initialize();
    }
 
    // Destructor
    NuclearPotentialIsospin::~NuclearPotentialIsospin() {}
 
    void NuclearPotentialIsospin::initialize() {
      const G4double ZOverA = ((G4double) theZ) / ((G4double) theA);
 
      const G4double mp = ParticleTable::getINCLMass(Proton);
      const G4double mn = ParticleTable::getINCLMass(Neutron);
      const G4double ml = ParticleTable::getINCLMass(Lambda);
 
      const G4double theFermiMomentum = ParticleTable::getFermiMomentum(theA,theZ);
 
      fermiMomentum[Proton] = theFermiMomentum * Math::pow13(2.*ZOverA);
      const G4double theProtonFermiEnergy = std::sqrt(fermiMomentum[Proton]*fermiMomentum[Proton] + mp*mp) - mp;
      fermiEnergy[Proton] = theProtonFermiEnergy;
      // Use separation energies from the ParticleTable
      const G4double theProtonSeparationEnergy = ParticleTable::getSeparationEnergy(Proton,theA,theZ);
      separationEnergy[Proton] = theProtonSeparationEnergy;
      vProton = theProtonFermiEnergy + theProtonSeparationEnergy;
 
      fermiMomentum[Neutron] = theFermiMomentum * Math::pow13(2.*(1.-ZOverA));
      const G4double theNeutronFermiEnergy = std::sqrt(fermiMomentum[Neutron]*fermiMomentum[Neutron] + mn*mn) - mn;
      fermiEnergy[Neutron] = theNeutronFermiEnergy;
      // Use separation energies from the ParticleTable
      const G4double theNeutronSeparationEnergy = ParticleTable::getSeparationEnergy(Neutron,theA,theZ);
      separationEnergy[Neutron] = theNeutronSeparationEnergy;
      vNeutron = theNeutronFermiEnergy + theNeutronSeparationEnergy;
 
      const G4double separationEnergyDeltaPlusPlus = 2.*theProtonSeparationEnergy - theNeutronSeparationEnergy;
      separationEnergy[DeltaPlusPlus] = separationEnergyDeltaPlusPlus;
      separationEnergy[DeltaPlus] = theProtonSeparationEnergy;
      separationEnergy[DeltaZero] = theNeutronSeparationEnergy;
      const G4double separationEnergyDeltaMinus = 2.*theNeutronSeparationEnergy - theProtonSeparationEnergy;
      separationEnergy[DeltaMinus] = separationEnergyDeltaMinus;
 
      const G4double tinyMargin = 1E-7;
      vDeltaPlus = vProton;
      vDeltaZero = vNeutron;
      vDeltaPlusPlus = std::max(separationEnergyDeltaPlusPlus + tinyMargin, 2.*vDeltaPlus - vDeltaZero);
      vDeltaMinus = std::max(separationEnergyDeltaMinus + tinyMargin, 2.*vDeltaZero - vDeltaPlus);
      
      vSigmaMinus = -16.; // Repulsive potential, from Eur. Phys.J.A. (2016) 52:21
      vSigmaZero = -16.;  // hypothesis: same potential for each sigma
      vSigmaPlus = -16.;
 
      vLambda = 30.;
      const G4double asy = (theA - 2.*theZ)/theA;
      // Jose Luis Rodriguez-Sanchez et al., Rapid Communication PRC 98, 021602 (2018)
      if      (asy > 0.236) vLambda = 40.91;
      else if (asy > 0.133) vLambda = 56.549 - 678.73*asy + 4905.35*asy*asy - 9789.1*asy*asy*asy;
 
      const G4double theLambdaSeparationEnergy = ParticleTable::getSeparationEnergy(Lambda,theA,theZ);
 
      separationEnergy[PiPlus] = theProtonSeparationEnergy - theNeutronSeparationEnergy;
      separationEnergy[PiZero] = 0.;
      separationEnergy[PiMinus] = theNeutronSeparationEnergy - theProtonSeparationEnergy;
 
      separationEnergy[Eta]      = 0.;
      separationEnergy[Omega]    = 0.;
      separationEnergy[EtaPrime] = 0.;
      separationEnergy[Photon]   = 0.;
      
      separationEnergy[Lambda]      = theLambdaSeparationEnergy;
      separationEnergy[SigmaPlus]   = theProtonSeparationEnergy + theLambdaSeparationEnergy - theNeutronSeparationEnergy;
      separationEnergy[SigmaZero]   = theLambdaSeparationEnergy;
      separationEnergy[SigmaMinus]  = theNeutronSeparationEnergy + theLambdaSeparationEnergy - theProtonSeparationEnergy;
 
      separationEnergy[KPlus]       = theProtonSeparationEnergy - theLambdaSeparationEnergy;
      separationEnergy[KZero]       = (theNeutronSeparationEnergy - theLambdaSeparationEnergy);
      separationEnergy[KZeroBar]    = (theLambdaSeparationEnergy - theNeutronSeparationEnergy);
      separationEnergy[KMinus]      = 2.*theNeutronSeparationEnergy - theProtonSeparationEnergy-theLambdaSeparationEnergy;
 
      separationEnergy[KShort]      = (theNeutronSeparationEnergy - theLambdaSeparationEnergy);
      separationEnergy[KLong]       = (theNeutronSeparationEnergy - theLambdaSeparationEnergy);
 
      fermiEnergy[DeltaPlusPlus] = vDeltaPlusPlus - separationEnergy[DeltaPlusPlus];
      fermiEnergy[DeltaPlus] = vDeltaPlus - separationEnergy[DeltaPlus];
      fermiEnergy[DeltaZero] = vDeltaZero - separationEnergy[DeltaZero];
      fermiEnergy[DeltaMinus] = vDeltaMinus - separationEnergy[DeltaMinus];
      
      fermiEnergy[Lambda] = vLambda - separationEnergy[Lambda];
      if (fermiEnergy[Lambda] <= 0.)
         fermiMomentum[Lambda]=0.;
      else
         fermiMomentum[Lambda]=std::sqrt(std::pow(fermiEnergy[Lambda]+ml,2.0)-ml*ml);
 
      fermiEnergy[SigmaPlus] = vSigmaPlus - separationEnergy[SigmaPlus];
      fermiEnergy[SigmaZero] = vSigmaZero - separationEnergy[SigmaZero];
      fermiEnergy[SigmaMinus] = vSigmaMinus - separationEnergy[SigmaMinus];
 
      INCL_DEBUG("Table of separation energies [MeV] for A=" << theA << ", Z=" << theZ << ":" << '\n'
            << "  proton:  " << separationEnergy[Proton] << '\n'
            << "  neutron: " << separationEnergy[Neutron] << '\n'
            << "  delta++: " << separationEnergy[DeltaPlusPlus] << '\n'
            << "  delta+:  " << separationEnergy[DeltaPlus] << '\n'
            << "  delta0:  " << separationEnergy[DeltaZero] << '\n'
            << "  delta-:  " << separationEnergy[DeltaMinus] << '\n'
            << "  pi+:     " << separationEnergy[PiPlus] << '\n'
            << "  pi0:     " << separationEnergy[PiZero] << '\n'
            << "  pi-:     " << separationEnergy[PiMinus] << '\n'
            << "  eta:     " << separationEnergy[Eta] << '\n'
            << "  omega:   " << separationEnergy[Omega] << '\n'
            << "  etaprime:" << separationEnergy[EtaPrime] << '\n'
            << "  photon:  " << separationEnergy[Photon] << '\n'
            << "  lambda:  " << separationEnergy[Lambda] << '\n'
            << "  sigmaplus:  " << separationEnergy[SigmaPlus] << '\n'
            << "  sigmazero:  " << separationEnergy[SigmaZero] << '\n'
            << "  sigmaminus:  " << separationEnergy[SigmaMinus] << '\n'
            << "  kplus:  " << separationEnergy[KPlus] << '\n'
            << "  kzero:  " << separationEnergy[KZero] << '\n'
            << "  kzerobar:  " << separationEnergy[KZeroBar] << '\n'
            << "  kminus:  " << separationEnergy[KMinus] << '\n'
            << "  kshort:  " << separationEnergy[KShort] << '\n'
            << "  klong:  " << separationEnergy[KLong] << '\n'
            );
 
      INCL_DEBUG("Table of Fermi energies [MeV] for A=" << theA << ", Z=" << theZ << ":" << '\n'
            << "  proton:  " << fermiEnergy[Proton] << '\n'
            << "  neutron: " << fermiEnergy[Neutron] << '\n'
            << "  delta++: " << fermiEnergy[DeltaPlusPlus] << '\n'
            << "  delta+:  " << fermiEnergy[DeltaPlus] << '\n'
            << "  delta0:  " << fermiEnergy[DeltaZero] << '\n'
            << "  delta-:  " << fermiEnergy[DeltaMinus] << '\n'
            << "  lambda:  " << fermiEnergy[Lambda] << '\n'
            << "  sigma+:  " << fermiEnergy[SigmaPlus] << '\n'
            << "  sigma0:  " << fermiEnergy[SigmaZero] << '\n'
            << "  sigma-:  " << fermiEnergy[SigmaMinus] << '\n'
            );
 
      INCL_DEBUG("Table of Fermi momenta [MeV/c] for A=" << theA << ", Z=" << theZ << ":" << '\n'
            << "  proton:  " << fermiMomentum[Proton] << '\n'
            << "  neutron: " << fermiMomentum[Neutron] << '\n'
            );
    }
 
    G4double NuclearPotentialIsospin::computePotentialEnergy(const Particle *particle) const {
 
      switch( particle->getType() )
      {
        case Proton:
          return vProton;
          break;
        case Neutron:
          return vNeutron;
          break;
 
        case PiPlus:
        case PiZero:
        case PiMinus:
          return computePionPotentialEnergy(particle);
          break;
        
        case SigmaPlus:
          return vSigmaPlus;
          break;
        case SigmaZero:
          return vSigmaZero;
          break;
        case Lambda:
          return vLambda;
          break;
        case SigmaMinus:
          return vSigmaMinus;
          break;
 
        case Eta:
        case Omega:
        case EtaPrime:
          return computePionResonancePotentialEnergy(particle);
          break;
 
        case KPlus:
        case KZero:
        case KZeroBar:
        case KMinus:
        case KShort:
        case KLong:
          return computeKaonPotentialEnergy(particle);
          break;
 
        case Photon:
          return 0.0;
          break;
 
        case DeltaPlusPlus:
          return vDeltaPlusPlus;
          break;
        case DeltaPlus:
          return vDeltaPlus;
          break;
        case DeltaZero:
          return vDeltaZero;
          break;
        case DeltaMinus:
          return vDeltaMinus;
          break;
      case Composite:
    INCL_ERROR("No potential computed for particle of type Cluster.");
    return 0.0;
    break;
      case UnknownParticle:
    INCL_ERROR("Trying to compute potential energy for an unknown particle.");
    return 0.0;
    break;
      }
 
      INCL_ERROR("There is no potential for this type of particle.");
      return 0.0;
    }
 
  }
}