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G4FermiDecayProbability.cc
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26 // $Id: G4VFermiDecayProbability.cc,v 1.5 2006-06-29 20:13:13 gunter Exp $
27 //
28 // FermiBreakUp de-excitation model
29 // by V. Ivanchenko (July 2016)
30 //
31 
33 #include "G4FermiFragment.hh"
34 #include "G4PhysicalConstants.hh"
35 
37 {}
38 
40 {}
41 
42 G4double
44  G4double etot,
45  const G4FermiFragment* f1,
46  const G4FermiFragment* f2) const
47 {
48  G4double prob = 0.0;
49  G4double mass1 = f1->GetTotalEnergy();
50  G4double mass2 = f2->GetTotalEnergy();
51  //G4cout << "ComputeProbability M1= " << mass1 << " M2= " << mass2 << G4endl;
52  G4double ekin = etot - mass1 - mass2
53  - f1->GetCoulombBarrier(f2->GetA(), f2->GetZ(), 0.0);
54  //G4cout << " Ekin= " << ekin << G4endl;
55  if(ekin <= 0.0) { return prob; }
56 
57  // mass factors
58  G4double massFactor = mass1*mass2/(mass1 + mass2);
59  massFactor *= std::sqrt(massFactor);
60 
61  // Spin factor S_n
62  G4double S_n = 1.0;
63  if(spin >= 0) {
64  G4int spin1 = f1->GetSpin();
65  G4int spin2 = f2->GetSpin();
66  if(spin1 >= 0 && spin2 >= 0) {
67  S_n = (spin1+1)*(spin2+1);
68  }
69  }
70 
71  // Permutation Factor G_n
72  // search for identical fragments
73  G4double G_n = (f1 == f2) ? 0.5 : 1.0;
74 
75  prob = A*massFactor*S_n*G_n*std::sqrt(ekin);
76 
77  //G4cout << "prob= " << prob << " Coeff= " << Coeff << G4endl;
78  return prob;
79 }
G4double ComputeProbability(G4int Z, G4int A, G4int spin, G4double TotalE, const G4FermiFragment *f1, const G4FermiFragment *f2) const
G4double GetCoulombBarrier(G4int Ares, G4int Zres, G4double Eex) const
G4int GetSpin(void) const
G4int GetZ(void) const
int G4int
Definition: G4Types.hh:78
double A(double temperature)
G4int GetA(void) const
double G4double
Definition: G4Types.hh:76
G4double GetTotalEnergy(void) const