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25 //
26 //
27 // by V. Lara
28 //
29 // Modified:
30 // 23.08.2010 V.Ivanchenko general cleanup, move constructor and destructor
31 // the source, use G4Pow
32
33 #include "G4HETCFragment.hh"
34 #include "G4DeexPrecoParameters.hh"
35 #include "G4NuclearLevelData.hh"
36 #include "G4PhysicalConstants.hh"
37
38 G4HETCFragment::G4HETCFragment(const G4ParticleDefinition* part,
39 G4VCoulombBarrier* aCoulombBarrier)
40 : G4VPreCompoundFragment(part, aCoulombBarrier)
41 {
42 G4double r0 = theParameters->GetR0();
43 r2norm = r0*r0/(CLHEP::pi*CLHEP::hbarc*CLHEP::hbarc*CLHEP::hbarc);
44 }
45
46 G4double G4HETCFragment::CalcEmissionProbability(const G4Fragment& fp)
47 {
48 if (GetEnergyThreshold() <= 0.0) {
49 theEmissionProbability = 0.0;
50 return 0.0;
51 }
52 // Coulomb barrier is the lower limit
53 // of integration over kinetic energy
54 theEmissionProbability =
55 IntegrateEmissionProbability(theCoulombBarrier, theMaxKinEnergy, fp);
56
57 return theEmissionProbability;
58 }
59
60 G4double
61 G4HETCFragment::IntegrateEmissionProbability(G4double Low, G4double Up,
62 const G4Fragment& frag)
63 {
64 G4double U = frag.GetExcitationEnergy();
65
66 G4int P = frag.GetNumberOfParticles();
67 G4int H = frag.GetNumberOfHoles();
68 G4int N = P + H;
69 G4int Pb = P - theA;
70 G4int Nb = Pb + H;
71 if (Nb <= 0.0) { return 0.0; }
72
73 G4double ga = (6.0/pi2)*fNucData->GetLevelDensity(theFragZ,theFragA,U);
74 G4double gb = (6.0/pi2)*fNucData->GetLevelDensity(theResZ,theResA,U);
75
76 G4double A = G4double(P*P+H*H+P-3*H)/(4.0*ga);
77 G4double Ab = G4double(Pb*Pb+H*H+Pb-3*H)/(4.0*gb);
78 U = std::max(U-A,0.0);
79 if (U <= 0.0) { return 0.0; }
80
81 G4int Pf = P;
82 G4int Hf = H;
83 G4int Nf = N-1;
84 for (G4int i = 1; i < theA; ++i) {
85 Pf *= (P-i);
86 Hf *= (H-i);
87 Nf *= (N-1-i);
88 }
89
90 G4double X = std::max(Up - Ab + GetBeta(),0.0);
91 G4double Y = std::max(Up - Ab - Low, 0.0);
92
93 G4double Probability = r2norm*GetSpinFactor()*theReducedMass*GetAlpha()
94 *g4calc->Z23(theResA)*Pf*Hf*Nf*K(frag)*(X/Nb - Y/(Nb+1))
95 *U*g4calc->powN(gb*Y,Nb)/g4calc->powN(ga*U,N);
96
97 return Probability;
98 }
99