G4FermiBreakUpUtil Namespace Reference

Functions
G4double	CoulombBarrier (const G4int Z1, const G4int A1, const G4int Z2, const G4int A2, const G4double exc)
G4double	Probability (const G4int A, const G4FermiFragment *f1, const G4FermiFragment *f2, const G4double mass, const G4double exc)
G4bool	CheckSpinParity (const G4FermiFragment *f1, const G4FermiFragment *f2, const G4FermiFragment *f3)

Variables
const G4double	deltaR = 0.6*CLHEP::fermi
const G4double	coeff = 0.9

Function Documentation

CheckSpinParity()

G4bool G4FermiBreakUpUtil::CheckSpinParity	(	const G4FermiFragment *	f1,
		const G4FermiFragment *	f2,
		const G4FermiFragment *	f3 )

Definition at line 82 of file G4FermiBreakUpUtil.cc.

  {
    // check parity
    G4int spin1 = f1->TwoSpinParity();
    G4int spin2 = f2->TwoSpinParity();
    G4int spin3 = f3->TwoSpinParity();
    if ((spin3 > 0 && spin1*spin2 < 0) || (spin3 < 0 && spin1*spin2 > 0))
      return false;
 
    return true;
  }

Referenced by G4FermiFragmentsPoolVI::Initialise().

CoulombBarrier()

G4double G4FermiBreakUpUtil::CoulombBarrier	(	const G4int	Z1,
		const G4int	A1,
		const G4int	Z2,
		const G4int	A2,
		const G4double	exc )

Definition at line 42 of file G4FermiBreakUpUtil.cc.

                                                                              {
    const G4double r1 = G4NuclearRadii::RadiusCB(Z1, A1);
    const G4double r2 = G4NuclearRadii::RadiusCB(Z2, A2);
    G4double CB = coeff*CLHEP::elm_coupling*(Z1*Z2)/(r1 + r2 - deltaR);
    if(exc > 0.0) { CB /= (1.0 + std::sqrt(exc/((2*(A1 + A2))*CLHEP::MeV))); }
    return CB;
  }

Referenced by G4FermiPair::GetMinMass(), G4FermiFragmentsPoolVI::Initialise(), and Probability().

Probability()

G4double G4FermiBreakUpUtil::Probability	(	const G4int	A,
		const G4FermiFragment *	f1,
		const G4FermiFragment *	f2,
		const G4double	mass,
		const G4double	exc )

Definition at line 52 of file G4FermiBreakUpUtil.cc.

                                                                {
    G4double prob = 0.0;
    const G4double mass1 = f1->GetTotalEnergy();
    const G4double mass2 = f2->GetTotalEnergy();
    const G4double bCouloumb =
      CoulombBarrier(f1->GetZ(), f1->GetA(), f2->GetZ(), f2->GetA(), exc);
    if (mass < mass1 + mass2 + bCouloumb)
      return prob;
 
    // free energy
    const G4double e = mass - mass1 - mass2;
 
    // Spin factor S_n
    const G4int S_n = (std::abs(f1->TwoSpinParity())+1)
      *(std::abs(f2->TwoSpinParity())+1); 
 
    // mass factors
    const G4double x = mass1*mass2/(mass1 + mass2);
    G4double massFactor = x*std::sqrt(x);
 
    // Permutation Factor G_n - search for identical fragments
    G4double G_n = (f1 == f2) ? 0.5 : 1.0;
 
    prob = (A*S_n) * massFactor*G_n*std::sqrt(e);
    //G4cout << "prob= " << prob << " Coeff= " << Coeff << G4endl;
    return prob;
  }

Referenced by G4FermiFragmentsPoolVI::Initialise().

Variable Documentation

coeff

const G4double G4FermiBreakUpUtil::coeff = 0.9

Definition at line 39 of file G4FermiBreakUpUtil.cc.

Referenced by CoulombBarrier().

deltaR

const G4double G4FermiBreakUpUtil::deltaR = 0.6*CLHEP::fermi

Definition at line 38 of file G4FermiBreakUpUtil.cc.

Referenced by CoulombBarrier().