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G4FissionBarrier.cc
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26 // $Id: G4FissionBarrier.cc 96634 2016-04-27 09:31:49Z 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  static const G4double blimit = 100.0*CLHEP::GeV;
54  return (A < 65) ? blimit :
55  BarashenkovFissionBarrier(A,Z)/(1.0 + std::sqrt(U/(G4double)(2*A)));
56 }
57 
58 G4double
59 G4FissionBarrier::BarashenkovFissionBarrier(G4int A, G4int Z) const
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*CLHEP::MeV;
65  // and coulomb energy
66  static const G4double aCoul = 0.7053*CLHEP::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  G4int d = N - 2*(N/2) + Z - 2*(Z/2);
80 
81  G4double res = 0.0;
82  SPtr->GetPairingCorrection(N,Z,res);
83 
84  static const G4double D = 1.248*CLHEP::MeV;
85  return BF0 + D*d - res;
86 }
87 
static G4Pow * GetInstance()
Definition: G4Pow.cc:55
tuple x
Definition: test.py:50
int G4int
Definition: G4Types.hh:78
double A(double temperature)
static constexpr double MeV
const G4CameronShellPlusPairingCorrections * GetCameronShellPlusPairingCorrections() const
static constexpr double GeV
virtual ~G4FissionBarrier()
double D(double temp)
G4double Z23(G4int Z) const
Definition: G4Pow.hh:154
**D E S C R I P T I O N
Definition: HEPEvtcom.cc:77
static G4ShellCorrection * GetInstance()
double G4double
Definition: G4Types.hh:76
virtual G4double FissionBarrier(G4int A, G4int Z, G4double U) const final