G4HETCHe3.cc

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//
//
// by V. Lara
//
// Modified:
// 23.08.2010 V.Ivanchenko general cleanup, move constructor and destructor 
//            the source, use G4Pow

#include "G4HETCHe3.hh"
#include "G4He3.hh"

G4HETCHe3::G4HETCHe3() 
  : G4HETCChargedFragment(G4He3::He3(), &theHe3CoulombBarrier)
{}

G4HETCHe3::~G4HETCHe3() 
{}

G4double G4HETCHe3::GetAlpha() const
{
  G4double C = 0.0;
  if (theFragZ <= 30) 
    {
      C = 0.10;
    } 
  else if (theFragZ <= 50) 
    {
      C = 0.1 + -((theFragZ-50.)/20.)*0.02;
    } 
  else if (theFragZ < 70) 
    {
      C = 0.08 + -((theFragZ-70.)/20.)*0.02;
    }
  else 
    {
      C = 0.06;
    }
  return 1.0 + C*(4.0/3.0);
}
  
G4double G4HETCHe3::GetBeta() const
{
  return -theCoulombBarrier;
}

G4double G4HETCHe3::GetSpinFactor() const
{
  // 2s+1
  return 2.0;
}    

G4double G4HETCHe3::K(const G4Fragment & aFragment)
{
  // Number of protons in emitted fragment
  G4int Pa = theZ;
  // Number of neutrons in emitted fragment 
  G4int Na = theA - Pa;

  G4double r = G4double(theResZ)/G4double(theResA);

  G4int P = aFragment.GetNumberOfParticles();
  G4int H = aFragment.GetNumberOfHoles();

  G4double result = 0.0;
  if (P > 2)
    {
      result = 3.0/(P*(P-1.0)*(P-2.0)) * 
  (H*(H-1.0)*(H-2.0)*r*r*(r-1.0) +
   H*(H-1.0)*(2.0*Na*r*(1.0-r)+Pa*r*r) +
   H*(Pa*(Pa-1.0)*(r-1.0)+2.0*Na*Pa*r) +
   Pa*Na*(Pa-1.0));

      result /= 3.0*r*r*(1.0 - r);
    }
  return std::max(0.0,result);
}