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25 //
26 //
27 //
28 // Hadronic Process: Nuclear De-excitations
29 // by V. Lara (Oct 1998)
30 //
31 //J. M. Quesada (May 2009): sigma_sym (SigmaS)
32 //J. M. Quesada (30.10.09): retuning for IAEA
33
34 #include "G4FissionParameters.hh"
35 #include "G4SystemOfUnits.hh"
36
37 G4FissionParameters::G4FissionParameters()
38 : A1(134),A2(141),A3((A1 + A2)*0.5),As(0.0),
39 SigmaS(0.),w(0.0)
40 {}
41
42 G4FissionParameters::~G4FissionParameters()
43 {}
44
45 void G4FissionParameters::DefineParameters(G4i
46 G4double FissionBarrier)
47 {
48 // to avoid usage of units
49 G4double U = std::min(200., ExEnergy/CLHEP::
50
51 As = A*0.5;
52
53 if (A <= 235) { Sigma2 = 5.6; }
54 else { Sigma2 = 5.6 + 0.096*(A-235)
55
56 Sigma1 = 0.5*Sigma2;
57
58 //JMQ 310509
59 // if (SigmaS > 20.0) SigmaS = 20.0;
60 // SigmaS*=1.3;
61 //JMQ 301009: retuning (after CEM transition
62 SigmaS = 0.8*G4Exp(0.00553*U + 2.1386);
63
64 G4double wa = 0.0;
65 w = 0.0;
66 if (Z >= 90) {
67 if (U <= 16.25) { wa = G4Exp(0.5385*U-9.95
68 else { wa = G4Exp(0.09197*U-2.7
69 } else if (Z == 89) {
70 wa = G4Exp(0.09197*U-1.0808);
71 } else if (Z >= 82) {
72 G4double X = std::max(0.0, FissionBarrier/
73 wa = G4Exp(0.09197*(U-X) - 1.0808);
74 } else { // Z < 82
75 w = 1001.0;
76 }
77
78 if (Z >= 82) {
79 G4double x1 = (A1-As)/Sigma1;
80 G4double x2 = (A2-As)/Sigma2;
81 G4double FasymAsym = 2*LocalExp(x2) + Loca
82
83 G4double x3 = (As-A3)/SigmaS;
84 G4double FsymA1A2 = LocalExp(x3);
85
86 G4double w1 = std::max(1.03*wa - FasymAsym
87 G4double w2 = std::max(1.0 - FsymA1A2*wa,
88
89 w = w1/w2;
90
91 if (A < 227) { w *= G4Exp(0.3*(227-A)); }
92 }
93 }
94
95
96