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26 //
27 /// \file electromagnetic/TestEm10/src/XTRTransparentRegRadModel.cc
28 /// \brief Implementation of the XTRTransparentRegRadModel class
29 //
30 //
31
32 #include "XTRTransparentRegRadModel.hh"
33
34 #include "G4Gamma.hh"
35 #include "G4Integrator.hh"
36 #include "G4PhysicalConstants.hh"
37 #include "Randomize.hh"
38
39 #include <complex>
40
41 using namespace std;
42
43 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
44
45 ////////////////////////////////////////////////////////////////////////////
46 //
47 // Constructor, destructor
48
49 XTRTransparentRegRadModel::XTRTransparentRegRadModel(G4LogicalVolume* anEnvelope,
50 G4Material* foilMat, G4Material* gasMat,
51 G4double a, G4double b, G4int n,
52 const G4String& processName)
53 : G4VXTRenergyLoss(anEnvelope, foilMat, gasMat, a, b, n, processName)
54 {
55 G4cout << "Regular transparent X-ray TR radiator EM process is called" << G4endl;
56
57 // Build energy and angular integral spectra of X-ray TR photons from
58 // a radiator
59 fExitFlux = true;
60 fAlphaPlate = 10000;
61 fAlphaGas = 1000;
62
63 // BuildTable();
64 }
65
66 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
67
68 XTRTransparentRegRadModel::~XTRTransparentRegRadModel()
69 {
70 ;
71 }
72
73 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
74
75 G4double XTRTransparentRegRadModel::SpectralXTRdEdx(G4double energy)
76 {
77 G4double result, sum = 0., tmp, cof1, cof2, cofMin, cofPHC, aMa, bMb, sigma;
78 G4int k, kMax, kMin;
79
80 aMa = GetPlateLinearPhotoAbs(energy);
81 bMb = GetGasLinearPhotoAbs(energy);
82
83 // if(fCompton)
84 {
85 aMa += GetPlateCompton(energy);
86 bMb += GetGasCompton(energy);
87 }
88 aMa *= fPlateThick;
89 bMb *= fGasThick;
90
91 sigma = aMa + bMb;
92
93 cofPHC = 4 * pi * hbarc;
94 cofPHC *= 200. / 197.;
95 tmp = (fSigma1 - fSigma2) / cofPHC / energy;
96 cof1 = fPlateThick * tmp;
97 cof2 = fGasThick * tmp;
98
99 cofMin = energy * (fPlateThick + fGasThick) / fGamma / fGamma;
100 cofMin += (fPlateThick * fSigma1 + fGasThick * fSigma2) / energy;
101 cofMin /= cofPHC;
102
103 // if (fGamma < 1200) kMin = G4int(cofMin); // 1200 ?
104 // else kMin = 1;
105
106 kMin = G4int(cofMin);
107 if (cofMin > kMin) kMin++;
108
109 // tmp = (fPlateThick + fGasThick)*energy*fMaxThetaTR;
110 // tmp /= cofPHC;
111 // kMax = G4int(tmp);
112 // if(kMax < 0) kMax = 0;
113 // kMax += kMin;
114
115 kMax = kMin + 9; // 5; // 9; // kMin + G4int(tmp);
116
117 // tmp /= fGamma;
118 // if( G4int(tmp) < kMin ) kMin = G4int(tmp);
119 // G4cout<<"kMin = "<<kMin<<"; kMax = "<<kMax<<G4endl;
120
121 for (k = kMin; k <= kMax; k++) {
122 tmp = pi * fPlateThick * (k + cof2) / (fPlateThick + fGasThick);
123 result = (k - cof1) * (k - cof1) * (k + cof2) * (k + cof2);
124
125 if (k == kMin && kMin == G4int(cofMin)) {
126 sum += 0.5 * sin(tmp) * sin(tmp) * std::abs(k - cofMin) / result;
127 }
128 else {
129 sum += sin(tmp) * sin(tmp) * std::abs(k - cofMin) / result;
130 }
131 // G4cout<<"k = "<<k<<"; sum = "<<sum<<G4endl;
132 }
133 result = 4. * (cof1 + cof2) * (cof1 + cof2) * sum / energy;
134 result *= (1. - exp(-fPlateNumber * sigma)) / (1. - exp(-sigma));
135 return result;
136 }
137
138 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
139 //
140 // Approximation for radiator interference factor for the case of
141 // fully Regular radiator. The plate and gas gap thicknesses are fixed .
142 // The mean values of the plate and gas gap thicknesses
143 // are supposed to be about XTR formation zones but much less than
144 // mean absorption length of XTR photons in coresponding material.
145
146 G4double XTRTransparentRegRadModel::GetStackFactor(G4double energy, G4double gamma,
147 G4double varAngle)
148 {
149 /*
150 G4double result, Za, Zb, Ma, Mb, sigma;
151
152 Za = GetPlateFormationZone(energy,gamma,varAngle);
153 Zb = GetGasFormationZone(energy,gamma,varAngle);
154 Ma = GetPlateLinearPhotoAbs(energy);
155 Mb = GetGasLinearPhotoAbs(energy);
156 sigma = Ma*fPlateThick + Mb*fGasThick;
157
158 G4complex Ca(1.0+0.5*fPlateThick*Ma/fAlphaPlate,fPlateThick/Za/fAlphaPlate);
159 G4complex Cb(1.0+0.5*fGasThick*Mb/fAlphaGas,fGasThick/Zb/fAlphaGas);
160
161 G4complex Ha = pow(Ca,-fAlphaPlate);
162 G4complex Hb = pow(Cb,-fAlphaGas);
163 G4complex H = Ha*Hb;
164 G4complex F1 = (1.0 - Ha)*(1.0 - Hb )/(1.0 - H)
165 * G4double(fPlateNumber) ;
166 G4complex F2 = (1.0-Ha)*(1.0-Ha)*Hb/(1.0-H)/(1.0-H)
167 * (1.0 - exp(-0.5*fPlateNumber*sigma)) ;
168 // *(1.0 - pow(H,fPlateNumber)) ;
169 G4complex R = (F1 + F2)*OneInterfaceXTRdEdx(energy,gamma,varAngle);
170 // G4complex R = F2*OneInterfaceXTRdEdx(energy,gamma,varAngle);
171 result = 2.0*real(R);
172 return result;
173 */
174 // numerically unstable result
175
176 G4double result, Qa, Qb, Q, aZa, bZb, aMa, bMb, D, sigma;
177
178 aZa = fPlateThick / GetPlateFormationZone(energy, gamma, varAngle);
179 bZb = fGasThick / GetGasFormationZone(energy, gamma, varAngle);
180 aMa = fPlateThick * GetPlateLinearPhotoAbs(energy);
181 bMb = fGasThick * GetGasLinearPhotoAbs(energy);
182 sigma = aMa * fPlateThick + bMb * fGasThick;
183 Qa = exp(-0.5 * aMa);
184 Qb = exp(-0.5 * bMb);
185 Q = Qa * Qb;
186
187 G4complex Ha(Qa * cos(aZa), -Qa * sin(aZa));
188 G4complex Hb(Qb * cos(bZb), -Qb * sin(bZb));
189 G4complex H = Ha * Hb;
190 G4complex Hs = conj(H);
191 D = 1.0 / ((1 - Q) * (1 - Q) + 4 * Q * sin(0.5 * (aZa + bZb)) * sin(0.5 * (aZa + bZb)));
192 G4complex F1 = (1.0 - Ha) * (1.0 - Hb) * (1.0 - Hs) * G4double(fPlateNumber) * D;
193 G4complex F2 = (1.0 - Ha) * (1.0 - Ha) * Hb * (1.0 - Hs)
194 * (1.0 - Hs)
195 // * (1.0 - pow(H,fPlateNumber)) * D*D;
196 * (1.0 - exp(-0.5 * fPlateNumber * sigma)) * D * D;
197 G4complex R = (F1 + F2) * OneInterfaceXTRdEdx(energy, gamma, varAngle);
198 result = 2.0 * real(R);
199 return result;
200 }
201