| Geant4 Cross Reference |
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25 //
26 //
27 // Hadronic Process: Nuclear De-excitations
28 // by V. Lara (Oct 1998)
29 //
30 // 17.11.2010 V.Ivanchenko cleanup and add usa
31 // 21.03.2013 V.Ivanchenko redesign parameters
32
33 #include "G4FissionBarrier.hh"
34 #include "G4CameronShellPlusPairingCorrections
35 #include "G4NuclearLevelData.hh"
36 #include "G4ShellCorrection.hh"
37 #include "G4SystemOfUnits.hh"
38 #include "G4Pow.hh"
39
40 G4FissionBarrier::G4FissionBarrier()
41 {
42 SPtr = G4NuclearLevelData::GetInstance()->Ge
43 ->GetCameronShellPlusPairingCorrections();
44 }
45
46 G4FissionBarrier::~G4FissionBarrier()
47 {}
48
49 G4double
50 G4FissionBarrier::FissionBarrier(G4int A, G4in
51 // Compute fission barrier according with Ba
52 // prescription for A >= 65
53 {
54 static const G4double blimit = 100.0*CLHEP::
55 return (A >= 65) ? BarashenkovFissionBarrier
56 /(1.0 + std::sqrt(U/(G4double)(2*A))) : bl
57 }
58
59 G4double
60 G4FissionBarrier::BarashenkovFissionBarrier(G4
61 // Calculates Fission Barrier heights
62 {
63 // Liquid drop model parameters for
64 // surface energy of a spherical nucleus
65 static const G4double aSurf = 17.9439*CLHEP:
66 // and coulomb energy
67 static const G4double aCoul = 0.7053*CLHEP::
68 static const G4double k = 1.7826;
69 G4int N = A - Z;
70
71 // fissibility parameter
72 G4double x = (aCoul/(2.0*aSurf))*(Z*Z)/stati
73 x /= (1.0 - k*(N-Z)*(N-Z)/static_cast<G4doub
74
75 // Liquid drop model part of Fission Barrier
76 G4double BF0 = aSurf*G4Pow::GetInstance()->Z
77 if (x <= 2./3.) { BF0 *= 0.38*(0.75 - x); }
78 else { BF0 *= 0.83*(1. - x)*(1. - x)*(1. - x
79
80 G4int d = N - 2*(N/2) + Z - 2*(Z/2);
81
82 G4double res = 0.0;
83 SPtr->GetPairingCorrection(N,Z,res);
84
85 static const G4double D = 1.248*CLHEP::MeV;
86 return BF0 + D*d - res;
87 }
88
89