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25 //
26 /// \file medical/fanoCavity/src/MyMollerBhabh
27 /// \brief Implementation of the MyMollerBhabh
28 //
29 //
30 //....oooOO0OOooo........oooOO0OOooo........oo
31 //....oooOO0OOooo........oooOO0OOooo........oo
32
33 #include "MyMollerBhabhaModel.hh"
34
35 #include "G4PhysicalConstants.hh"
36 #include "G4SystemOfUnits.hh"
37
38 //....oooOO0OOooo........oooOO0OOooo........oo
39
40 using namespace std;
41
42 MyMollerBhabhaModel::MyMollerBhabhaModel(const
43 : G4MollerBhabhaModel(p, nam)
44 {}
45
46 //....oooOO0OOooo........oooOO0OOooo........oo
47
48 MyMollerBhabhaModel::~MyMollerBhabhaModel() {}
49
50 //....oooOO0OOooo........oooOO0OOooo........oo
51
52 G4double MyMollerBhabhaModel::ComputeDEDXPerVo
53
54
55 {
56 if (!particle) SetParticle(p);
57 // calculate the dE/dx due to the ionization
58
59 G4double electronDensity = material->GetElec
60 G4double Zeff = electronDensity / material->
61 G4double th = 0.25 * sqrt(Zeff) * keV;
62 G4double tkin = kineticEnergy;
63 G4bool lowEnergy = false;
64 if (kineticEnergy < th) {
65 tkin = th;
66 lowEnergy = true;
67 }
68 G4double tau = tkin / electron_mass_c2;
69 G4double gam = tau + 1.0;
70 G4double gamma2 = gam * gam;
71 G4double beta2 = 1. - 1. / gamma2;
72 // G4double bg2 = beta2*gamma2;
73
74 G4double eexc = material->GetIonisation()->G
75 eexc /= electron_mass_c2;
76 G4double eexc2 = eexc * eexc;
77
78 G4double d = min(cutEnergy, MaxSecondaryEner
79 G4double dedx;
80
81 // electron
82 if (isElectron) {
83 dedx = log(2.0 * (tau + 2.0) / eexc2) - 1.
84 + (0.5 * d * d + (2.0 * tau + 1.) *
85
86 // positron
87 }
88 else {
89 G4double d2 = d * d * 0.5;
90 G4double d3 = d2 * d / 1.5;
91 G4double d4 = d3 * d * 3.75;
92 G4double y = 1.0 / (1.0 + gam);
93 dedx =
94 log(2.0 * (tau + 2.0) / eexc2) + log(tau
95 - beta2 * (tau + 2.0 * d - y * (3.0 * d2
96 }
97
98 // do not apply density correction
99 // G4double cden = material->GetIonisation(
100 // G4double mden = material->GetIonisation(
101 // G4double aden = material->GetIonisation(
102 // G4double x0den = material->GetIonisation(
103 // G4double x1den = material->GetIonisation(
104 // G4double x = log(bg2)/twoln10;
105
106 // if (x >= x0den) {
107 // dedx -= twoln10*x - cden;
108 // if (x < x1den) dedx -= aden*pow(x1den-x
109 // }
110
111 // now you can compute the total ionization
112 dedx *= twopi_mc2_rcl2 * electronDensity / b
113 if (dedx < 0.0) dedx = 0.0;
114
115 // lowenergy extrapolation
116
117 if (lowEnergy) {
118 if (kineticEnergy >= lowLimit)
119 dedx *= sqrt(tkin / kineticEnergy);
120 else
121 dedx *= sqrt(tkin * kineticEnergy) / low
122 }
123 return dedx;
124 }
125
126 //....oooOO0OOooo........oooOO0OOooo........oo
127