Geant4_10
G4FissionBarrier.cc
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26 // $Id: G4FissionBarrier.cc 68724 2013-04-05 09:26:32Z gcosmo $
27 //
28 // Hadronic Process: Nuclear De-excitations
29 // by V. Lara (Oct 1998)
30 //
31 // 17.11.2010 V.Ivanchenko cleanup and add usage of G4Pow
32 // 21.03.2013 V.Ivanchenko redesign parameters classes
33 
34 #include "G4FissionBarrier.hh"
35 #include "G4ShellCorrection.hh"
36 #include "G4SystemOfUnits.hh"
37 #include "G4Pow.hh"
38 
40 {
41  SPtr =
43 }
44 
46 {}
47 
48 G4double
50  // Compute fission barrier according with Barashenkov's
51  // prescription for A >= 65
52 {
53  if (A >= 65) {
54  return BarashenkovFissionBarrier(A,Z)/(1.0 + std::sqrt(U/(2.0*A)));
55  } else { return 100.0*GeV; }
56 }
57 
58 G4double
59 G4FissionBarrier::BarashenkovFissionBarrier(G4int A, G4int Z)
60  // Calculates Fission Barrier heights
61 {
62  // Liquid drop model parameters for
63  // surface energy of a spherical nucleus
64  static const G4double aSurf = 17.9439*MeV;
65  // and coulomb energy
66  static const G4double aCoul = 0.7053*MeV;
67  static const G4double k = 1.7826;
68  G4int N = A - Z;
69 
70  // fissibility parameter
71  G4double x = (aCoul/(2.0*aSurf))*(Z*Z)/static_cast<G4double>(A);
72  x /= (1.0 - k*(N-Z)*(N-Z)/static_cast<G4double>(A*A));
73 
74  // Liquid drop model part of Fission Barrier
75  G4double BF0 = aSurf*G4Pow::GetInstance()->Z23(A);
76  if (x <= 2./3.) { BF0 *= 0.38*(3./4.-x); }
77  else { BF0 *= 0.83*(1. - x)*(1. - x)*(1. - x); }
78 
79  //
80  G4double D = 1.248*MeV;
81  D *= (N - 2*(N/2) + Z - 2*(Z/2));
82 
83  return BF0 + D - SellPlusPairingCorrection(Z,N);
84 }
85 
static G4Pow * GetInstance()
Definition: G4Pow.cc:53
G4CameronShellPlusPairingCorrections * GetCameronShellPlusPairingCorrections()
tuple x
Definition: test.py:50
int G4int
Definition: G4Types.hh:78
Float_t Z
Definition: plot.C:39
G4double FissionBarrier(G4int A, G4int Z, G4double U)
G4double Z23(G4int Z) const
Definition: G4Pow.hh:153
**D E S C R I P T I O N
Definition: HEPEvtcom.cc:77
static G4ShellCorrection * GetInstance()
double G4double
Definition: G4Types.hh:76