G4CoulombBarrier.cc

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//
// Hadronic Process: Nuclear De-excitations
// by V. Lara (Dec 1999)
//
// 14-11-2007 modified barrier by JMQ (test30) 
// 15-11-2010 V.Ivanchenko use G4Pow and cleanup 

#include "G4CoulombBarrier.hh"
#include "G4PhysicalConstants.hh"
#include "G4SystemOfUnits.hh"
#include "G4Pow.hh"
#include "G4NuclearRadii.hh"

G4CoulombBarrier::G4CoulombBarrier(G4int A, G4int Z)
  : G4VCoulombBarrier(A, Z), g4calc(G4Pow::GetInstance())
{
  factor = CLHEP::elm_coupling*Z;
  SetParameters(0.4*G4NuclearRadii::RadiusCB(Z, A),1.3*CLHEP::fermi);
}

G4CoulombBarrier::~G4CoulombBarrier() 
{}

G4double G4CoulombBarrier::GetCoulombBarrier(
         G4int ARes, G4int ZRes, G4double) const 
{
  return factor*ZRes/(G4NuclearRadii::RadiusCB(ZRes,ARes) + GetRho());
  //return factor*ZRes/((G4NuclearRadii::RadiusCB(ZRes,ARes) 
  //       + GetRho())*(1.0 + std::sqrt(U/(G4double)(2*ARes))));
}

G4double G4CoulombBarrier::BarrierPenetrationFactor(G4int aZ) const 
{
  G4double res = 1.0;
  if(GetZ() == 1) {
    res = (aZ >= 70) ? 0.80 :
    (((0.2357e-5*aZ) - 0.42679e-3)*aZ + 0.27035e-1)*aZ + 0.19025;
    res += 0.06*(GetA() - 1);

  } else if(GetZ() == 2 && GetA() <= 4) {
    res = (aZ >= 70) ? 0.98 :
    (((0.23684e-5*aZ) - 0.42143e-3)*aZ + 0.25222e-1)*aZ + 0.46699;
    res += 0.12*(4 - GetA());
  }
  return res;
}