1 | // |
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2 | // ******************************************************************** |
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3 | // * License and Disclaimer * |
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4 | // * * |
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5 | // * The Geant4 software is copyright of the Copyright Holders of * |
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6 | // * the Geant4 Collaboration. It is provided under the terms and * |
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7 | // * conditions of the Geant4 Software License, included in the file * |
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8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
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9 | // * include a list of copyright holders. * |
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10 | // * * |
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11 | // * Neither the authors of this software system, nor their employing * |
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12 | // * institutes,nor the agencies providing financial support for this * |
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13 | // * work make any representation or warranty, express or implied, * |
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14 | // * regarding this software system or assume any liability for its * |
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15 | // * use. Please see the license in the file LICENSE and URL above * |
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16 | // * for the full disclaimer and the limitation of liability. * |
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17 | // * * |
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18 | // * This code implementation is the result of the scientific and * |
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19 | // * technical work of the GEANT4 collaboration. * |
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20 | // * By using, copying, modifying or distributing the software (or * |
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21 | // * any work based on the software) you agree to acknowledge its * |
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22 | // * use in resulting scientific publications, and indicate your * |
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23 | // * acceptance of all terms of the Geant4 Software license. * |
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24 | // ******************************************************************** |
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25 | // |
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26 | |
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27 | #include "G4LivermorePolarizedGammaConversionModel.hh" |
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28 | |
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29 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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30 | |
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31 | using namespace std; |
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32 | |
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33 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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34 | |
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35 | G4LivermorePolarizedGammaConversionModel::G4LivermorePolarizedGammaConversionModel(const G4ParticleDefinition*, |
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36 | const G4String& nam) |
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37 | :G4VEmModel(nam),isInitialised(false),meanFreePathTable(0),crossSectionHandler(0) |
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38 | { |
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39 | lowEnergyLimit = 1.0220000 * MeV; |
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40 | highEnergyLimit = 100 * GeV; |
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41 | SetLowEnergyLimit(lowEnergyLimit); |
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42 | SetHighEnergyLimit(highEnergyLimit); |
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43 | smallEnergy = 2.*MeV; |
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44 | |
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45 | |
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46 | verboseLevel= 0; |
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47 | // Verbosity scale: |
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48 | // 0 = nothing |
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49 | // 1 = warning for energy non-conservation |
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50 | // 2 = details of energy budget |
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51 | // 3 = calculation of cross sections, file openings, samping of atoms |
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52 | // 4 = entering in methods |
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53 | |
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54 | G4cout << "Livermore Polarized GammaConversion is constructed " << G4endl |
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55 | << "Energy range: " |
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56 | << lowEnergyLimit / keV << " keV - " |
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57 | << highEnergyLimit / GeV << " GeV" |
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58 | << G4endl; |
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59 | |
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60 | crossSectionHandler = new G4CrossSectionHandler(); |
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61 | crossSectionHandler->Initialise(0,1.0220*MeV,100.*GeV,400); |
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62 | |
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63 | |
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64 | } |
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65 | |
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66 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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67 | |
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68 | G4LivermorePolarizedGammaConversionModel::~G4LivermorePolarizedGammaConversionModel() |
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69 | { |
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70 | // if (meanFreePathTable) delete meanFreePathTable; |
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71 | if (crossSectionHandler) delete crossSectionHandler; |
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72 | } |
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73 | |
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74 | |
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75 | |
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76 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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77 | |
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78 | void G4LivermorePolarizedGammaConversionModel::Initialise(const G4ParticleDefinition* particle, |
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79 | const G4DataVector& cuts) |
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80 | { |
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81 | if (verboseLevel > 3) |
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82 | G4cout << "Calling G4LivermorePolarizedGammaConversionModel::Initialise()" << G4endl; |
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83 | |
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84 | if (crossSectionHandler) |
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85 | { |
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86 | crossSectionHandler->Clear(); |
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87 | delete crossSectionHandler; |
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88 | } |
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89 | |
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90 | |
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91 | // Energy limits |
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92 | |
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93 | if (LowEnergyLimit() < lowEnergyLimit) |
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94 | { |
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95 | G4cout << "G4LivermorePolarizedGammaConversionModel: low energy limit increased from " << |
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96 | LowEnergyLimit()/eV << " eV to " << lowEnergyLimit << " eV" << G4endl; |
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97 | SetLowEnergyLimit(lowEnergyLimit); |
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98 | } |
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99 | |
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100 | if (HighEnergyLimit() > highEnergyLimit) |
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101 | { |
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102 | G4cout << "G4LivermorePolarizedGammaConversionModel: high energy limit decreased from " << |
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103 | HighEnergyLimit()/GeV << " GeV to " << highEnergyLimit << " GeV" << G4endl; |
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104 | SetHighEnergyLimit(highEnergyLimit); |
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105 | } |
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106 | |
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107 | // Reading of data files - all materials are read |
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108 | |
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109 | crossSectionHandler = new G4CrossSectionHandler; |
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110 | crossSectionHandler->Clear(); |
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111 | G4String crossSectionFile = "pair/pp-cs-"; |
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112 | crossSectionHandler->LoadData(crossSectionFile); |
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113 | |
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114 | // meanFreePathTable = 0; |
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115 | //meanFreePathTable = crossSectionHandler->BuildMeanFreePathForMaterials(); |
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116 | |
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117 | |
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118 | // |
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119 | if (verboseLevel > 2) |
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120 | G4cout << "Loaded cross section files for Livermore Polarized GammaConversion model" << G4endl; |
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121 | |
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122 | InitialiseElementSelectors(particle,cuts); |
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123 | |
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124 | G4cout << "Livermore Polarized GammaConversion model is initialized " << G4endl |
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125 | << "Energy range: " |
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126 | << LowEnergyLimit() / keV << " keV - " |
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127 | << HighEnergyLimit() / GeV << " GeV" |
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128 | << G4endl; |
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129 | |
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130 | // |
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131 | |
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132 | if(isInitialised) return; |
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133 | |
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134 | fParticleChange = GetParticleChangeForGamma(); |
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135 | |
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136 | isInitialised = true; |
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137 | } |
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138 | |
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139 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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140 | |
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141 | G4double G4LivermorePolarizedGammaConversionModel::ComputeCrossSectionPerAtom( |
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142 | const G4ParticleDefinition*, |
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143 | G4double GammaEnergy, |
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144 | G4double Z, G4double, |
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145 | G4double, G4double) |
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146 | { |
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147 | if (verboseLevel > 3) |
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148 | G4cout << "Calling ComputeCrossSectionPerAtom() of G4LivermorePolarizedGammaConversionModel" << G4endl; |
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149 | |
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150 | G4double cs = crossSectionHandler->FindValue(G4int(Z), GammaEnergy); |
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151 | return cs; |
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152 | } |
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153 | |
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154 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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155 | |
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156 | void G4LivermorePolarizedGammaConversionModel::SampleSecondaries(std::vector<G4DynamicParticle*>* fvect, |
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157 | const G4MaterialCutsCouple* couple, |
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158 | const G4DynamicParticle* aDynamicGamma, |
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159 | G4double, |
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160 | G4double) |
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161 | { |
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162 | |
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163 | // Fluorescence generated according to: |
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164 | // J. Stepanek ,"A program to determine the radiation spectra due to a single atomic |
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165 | // subshell ionisation by a particle or due to deexcitation or decay of radionuclides", |
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166 | // Comp. Phys. Comm. 1206 pp 1-1-9 (1997) |
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167 | |
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168 | if (verboseLevel > 3) |
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169 | G4cout << "Calling SampleSecondaries() of G4LivermorePolarizedGammaConversionModel" << G4endl; |
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170 | |
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171 | G4double photonEnergy = aDynamicGamma->GetKineticEnergy(); |
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172 | // Within energy limit? |
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173 | |
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174 | if(photonEnergy <= lowEnergyLimit) |
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175 | { |
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176 | fParticleChange->ProposeTrackStatus(fStopAndKill); |
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177 | fParticleChange->SetProposedKineticEnergy(0.); |
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178 | return; |
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179 | } |
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180 | |
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181 | |
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182 | G4ThreeVector gammaPolarization0 = aDynamicGamma->GetPolarization(); |
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183 | G4ThreeVector gammaDirection0 = aDynamicGamma->GetMomentumDirection(); |
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184 | |
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185 | // Make sure that the polarization vector is perpendicular to the |
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186 | // gamma direction. If not |
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187 | |
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188 | if(!(gammaPolarization0.isOrthogonal(gammaDirection0, 1e-6))||(gammaPolarization0.mag()==0)) |
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189 | { // only for testing now |
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190 | gammaPolarization0 = GetRandomPolarization(gammaDirection0); |
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191 | } |
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192 | else |
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193 | { |
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194 | if ( gammaPolarization0.howOrthogonal(gammaDirection0) != 0) |
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195 | { |
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196 | gammaPolarization0 = GetPerpendicularPolarization(gammaDirection0, gammaPolarization0); |
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197 | } |
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198 | } |
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199 | |
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200 | // End of Protection |
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201 | |
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202 | |
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203 | G4double epsilon ; |
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204 | G4double epsilon0 = electron_mass_c2 / photonEnergy ; |
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205 | |
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206 | // Do it fast if photon energy < 2. MeV |
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207 | |
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208 | if (photonEnergy < smallEnergy ) |
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209 | { |
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210 | epsilon = epsilon0 + (0.5 - epsilon0) * G4UniformRand(); |
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211 | } |
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212 | else |
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213 | { |
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214 | |
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215 | // Select randomly one element in the current material |
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216 | |
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217 | // G4int Z = crossSectionHandler->SelectRandomAtom(couple,photonEnergy); |
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218 | //const G4Element* element = crossSectionHandler->SelectRandomElement(couple,photonEnergy); |
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219 | |
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220 | const G4ParticleDefinition* particle = aDynamicGamma->GetDefinition(); |
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221 | const G4Element* element = SelectRandomAtom(couple,particle,photonEnergy); |
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222 | |
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223 | if (element == 0) |
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224 | { |
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225 | G4cout << "G4LivermorePolarizedGammaConversionModel::PostStepDoIt - element = 0" << G4endl; |
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226 | } |
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227 | G4IonisParamElm* ionisation = element->GetIonisation(); |
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228 | if (ionisation == 0) |
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229 | { |
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230 | G4cout << "G4LivermorePolarizedGammaConversionModel::PostStepDoIt - ionisation = 0" << G4endl; |
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231 | } |
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232 | |
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233 | |
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234 | |
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235 | // Extract Coulomb factor for this Element |
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236 | |
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237 | G4double fZ = 8. * (ionisation->GetlogZ3()); |
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238 | if (photonEnergy > 50. * MeV) fZ += 8. * (element->GetfCoulomb()); |
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239 | |
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240 | // Limits of the screening variable |
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241 | G4double screenFactor = 136. * epsilon0 / (element->GetIonisation()->GetZ3()) ; |
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242 | G4double screenMax = exp ((42.24 - fZ)/8.368) - 0.952 ; |
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243 | G4double screenMin = std::min(4.*screenFactor,screenMax) ; |
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244 | |
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245 | // Limits of the energy sampling |
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246 | G4double epsilon1 = 0.5 - 0.5 * sqrt(1. - screenMin / screenMax) ; |
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247 | G4double epsilonMin = std::max(epsilon0,epsilon1); |
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248 | G4double epsilonRange = 0.5 - epsilonMin ; |
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249 | |
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250 | // Sample the energy rate of the created electron (or positron) |
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251 | G4double screen; |
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252 | G4double gReject ; |
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253 | |
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254 | G4double f10 = ScreenFunction1(screenMin) - fZ; |
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255 | G4double f20 = ScreenFunction2(screenMin) - fZ; |
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256 | G4double normF1 = std::max(f10 * epsilonRange * epsilonRange,0.); |
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257 | G4double normF2 = std::max(1.5 * f20,0.); |
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258 | |
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259 | do { |
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260 | if (normF1 / (normF1 + normF2) > G4UniformRand() ) |
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261 | { |
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262 | epsilon = 0.5 - epsilonRange * pow(G4UniformRand(), 0.3333) ; |
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263 | screen = screenFactor / (epsilon * (1. - epsilon)); |
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264 | gReject = (ScreenFunction1(screen) - fZ) / f10 ; |
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265 | } |
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266 | else |
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267 | { |
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268 | epsilon = epsilonMin + epsilonRange * G4UniformRand(); |
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269 | screen = screenFactor / (epsilon * (1 - epsilon)); |
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270 | gReject = (ScreenFunction2(screen) - fZ) / f20 ; |
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271 | |
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272 | |
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273 | } |
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274 | } while ( gReject < G4UniformRand() ); |
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275 | |
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276 | } // End of epsilon sampling |
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277 | |
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278 | // Fix charges randomly |
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279 | |
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280 | G4double electronTotEnergy; |
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281 | G4double positronTotEnergy; |
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282 | |
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283 | |
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284 | if (CLHEP::RandBit::shootBit()) |
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285 | { |
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286 | electronTotEnergy = (1. - epsilon) * photonEnergy; |
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287 | positronTotEnergy = epsilon * photonEnergy; |
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288 | } |
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289 | else |
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290 | { |
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291 | positronTotEnergy = (1. - epsilon) * photonEnergy; |
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292 | electronTotEnergy = epsilon * photonEnergy; |
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293 | } |
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294 | |
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295 | // Scattered electron (positron) angles. ( Z - axis along the parent photon) |
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296 | // Universal distribution suggested by L. Urban (Geant3 manual (1993) Phys211), |
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297 | // derived from Tsai distribution (Rev. Mod. Phys. 49, 421 (1977) |
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298 | |
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299 | G4double u; |
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300 | const G4double a1 = 0.625; |
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301 | G4double a2 = 3. * a1; |
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302 | |
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303 | if (0.25 > G4UniformRand()) |
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304 | { |
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305 | u = - log(G4UniformRand() * G4UniformRand()) / a1 ; |
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306 | } |
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307 | else |
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308 | { |
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309 | u = - log(G4UniformRand() * G4UniformRand()) / a2 ; |
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310 | } |
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311 | |
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312 | G4double Ene = electronTotEnergy/electron_mass_c2; // Normalized energy |
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313 | |
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314 | G4double cosTheta = 0.; |
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315 | G4double sinTheta = 0.; |
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316 | |
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317 | SetTheta(&cosTheta,&sinTheta,Ene); |
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318 | |
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319 | // G4double theta = u * electron_mass_c2 / photonEnergy ; |
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320 | // G4double phi = twopi * G4UniformRand() ; |
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321 | |
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322 | G4double phi,psi=0.; |
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323 | |
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324 | //corrected e+ e- angular angular distribution //preliminary! |
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325 | |
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326 | // if(photonEnergy>50*MeV) |
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327 | // { |
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328 | phi = SetPhi(photonEnergy); |
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329 | psi = SetPsi(photonEnergy,phi); |
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330 | // } |
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331 | //else |
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332 | // { |
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333 | //psi = G4UniformRand()*2.*pi; |
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334 | //phi = pi; // coplanar |
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335 | // } |
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336 | |
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337 | Psi = psi; |
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338 | Phi = phi; |
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339 | //G4cout << "PHI " << phi << G4endl; |
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340 | //G4cout << "PSI " << psi << G4endl; |
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341 | |
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342 | G4double phie = psi; //azimuthal angle for the electron |
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343 | |
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344 | G4double dirX = sinTheta*cos(phie); |
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345 | G4double dirY = sinTheta*sin(phie); |
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346 | G4double dirZ = cosTheta; |
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347 | G4ThreeVector electronDirection(dirX,dirY,dirZ); |
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348 | // Kinematics of the created pair: |
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349 | // the electron and positron are assumed to have a symetric angular |
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350 | // distribution with respect to the Z axis along the parent photon |
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351 | |
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352 | //G4double localEnergyDeposit = 0. ; |
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353 | |
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354 | G4double electronKineEnergy = std::max(0.,electronTotEnergy - electron_mass_c2) ; |
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355 | |
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356 | SystemOfRefChange(gammaDirection0,electronDirection, |
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357 | gammaPolarization0); |
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358 | |
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359 | G4DynamicParticle* particle1 = new G4DynamicParticle (G4Electron::Electron(), |
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360 | electronDirection, |
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361 | electronKineEnergy); |
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362 | |
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363 | // The e+ is always created (even with kinetic energy = 0) for further annihilation |
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364 | |
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365 | Ene = positronTotEnergy/electron_mass_c2; // Normalized energy |
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366 | |
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367 | cosTheta = 0.; |
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368 | sinTheta = 0.; |
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369 | |
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370 | SetTheta(&cosTheta,&sinTheta,Ene); |
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371 | G4double phip = phie+phi; //azimuthal angle for the positron |
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372 | |
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373 | dirX = sinTheta*cos(phip); |
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374 | dirY = sinTheta*sin(phip); |
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375 | dirZ = cosTheta; |
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376 | G4ThreeVector positronDirection(dirX,dirY,dirZ); |
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377 | |
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378 | G4double positronKineEnergy = std::max(0.,positronTotEnergy - electron_mass_c2) ; |
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379 | SystemOfRefChange(gammaDirection0,positronDirection, |
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380 | gammaPolarization0); |
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381 | |
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382 | // Create G4DynamicParticle object for the particle2 |
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383 | G4DynamicParticle* particle2 = new G4DynamicParticle(G4Positron::Positron(), |
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384 | positronDirection, positronKineEnergy); |
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385 | |
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386 | |
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387 | fvect->push_back(particle1); |
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388 | fvect->push_back(particle2); |
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389 | |
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390 | |
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391 | |
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392 | // Kill the incident photon |
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393 | |
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394 | |
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395 | |
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396 | // Create lists of pointers to DynamicParticles (photons and electrons) |
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397 | // (Is the electron vector necessary? To be checked) |
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398 | // std::vector<G4DynamicParticle*>* photonVector = 0; |
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399 | //std::vector<G4DynamicParticle*> electronVector; |
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400 | |
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401 | fParticleChange->ProposeMomentumDirection( 0., 0., 0. ); |
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402 | fParticleChange->SetProposedKineticEnergy(0.); |
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403 | fParticleChange->ProposeTrackStatus(fStopAndKill); |
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404 | |
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405 | } |
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406 | |
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407 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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408 | |
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409 | G4double G4LivermorePolarizedGammaConversionModel::ScreenFunction1(G4double screenVariable) |
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410 | { |
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411 | // Compute the value of the screening function 3*phi1 - phi2 |
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412 | |
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413 | G4double value; |
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414 | |
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415 | if (screenVariable > 1.) |
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416 | value = 42.24 - 8.368 * log(screenVariable + 0.952); |
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417 | else |
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418 | value = 42.392 - screenVariable * (7.796 - 1.961 * screenVariable); |
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419 | |
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420 | return value; |
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421 | } |
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422 | |
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423 | |
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424 | |
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425 | G4double G4LivermorePolarizedGammaConversionModel::ScreenFunction2(G4double screenVariable) |
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426 | { |
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427 | // Compute the value of the screening function 1.5*phi1 - 0.5*phi2 |
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428 | |
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429 | G4double value; |
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430 | |
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431 | if (screenVariable > 1.) |
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432 | value = 42.24 - 8.368 * log(screenVariable + 0.952); |
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433 | else |
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434 | value = 41.405 - screenVariable * (5.828 - 0.8945 * screenVariable); |
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435 | |
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436 | return value; |
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437 | } |
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438 | |
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439 | |
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440 | void G4LivermorePolarizedGammaConversionModel::SetTheta(G4double* p_cosTheta, G4double* p_sinTheta, G4double Energy) |
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441 | { |
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442 | |
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443 | // to avoid computational errors since Theta could be very small |
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444 | // Energy in Normalized Units (!) |
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445 | |
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446 | G4double Momentum = sqrt(Energy*Energy -1); |
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447 | G4double Rand = G4UniformRand(); |
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448 | |
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449 | *p_cosTheta = (Energy*((2*Rand)- 1) + Momentum)/((Momentum*(2*Rand-1))+Energy); |
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450 | *p_sinTheta = (2*sqrt(Rand*(1-Rand)))/(Momentum*(2*Rand-1)+Energy); |
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451 | } |
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452 | |
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453 | |
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454 | |
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455 | G4double G4LivermorePolarizedGammaConversionModel::SetPhi(G4double Energy) |
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456 | { |
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457 | |
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458 | |
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459 | G4double value = 0.; |
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460 | G4double Ene = Energy/MeV; |
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461 | |
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462 | G4double pl[4]; |
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463 | |
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464 | |
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465 | G4double pt[2]; |
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466 | G4double xi = 0; |
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467 | G4double xe = 0.; |
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468 | G4double n1=0.; |
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469 | G4double n2=0.; |
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470 | |
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471 | |
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472 | if (Ene>=50.) |
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473 | { |
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474 | const G4double ay0=5.6, by0=18.6, aa0=2.9, ba0 = 8.16E-3; |
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475 | const G4double aw = 0.0151, bw = 10.7, cw = -410.; |
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476 | |
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477 | const G4double axc = 3.1455, bxc = -1.11, cxc = 310.; |
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478 | |
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479 | pl[0] = Fln(ay0,by0,Ene); |
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480 | pl[1] = aa0 + ba0*(Ene); |
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481 | pl[2] = Poli(aw,bw,cw,Ene); |
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482 | pl[3] = Poli(axc,bxc,cxc,Ene); |
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483 | |
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484 | const G4double abf = 3.1216, bbf = 2.68; |
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485 | pt[0] = -1.4; |
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486 | pt[1] = abf + bbf/Ene; |
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487 | |
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488 | |
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489 | |
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490 | //G4cout << "PL > 50. "<< pl[0] << " " << pl[1] << " " << pl[2] << " " <<pl[3] << " " << G4endl; |
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491 | |
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492 | xi = 3.0; |
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493 | xe = Encu(pl,pt,xi); |
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494 | //G4cout << "ENCU "<< xe << G4endl; |
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495 | n1 = Fintlor(pl,pi) - Fintlor(pl,xe); |
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496 | n2 = Finttan(pt,xe) - Finttan(pt,0.); |
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497 | } |
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498 | else |
---|
499 | { |
---|
500 | const G4double ay0=0.144, by0=0.11; |
---|
501 | const G4double aa0=2.7, ba0 = 2.74; |
---|
502 | const G4double aw = 0.21, bw = 10.8, cw = -58.; |
---|
503 | const G4double axc = 3.17, bxc = -0.87, cxc = -6.; |
---|
504 | |
---|
505 | pl[0] = Fln(ay0, by0, Ene); |
---|
506 | pl[1] = Fln(aa0, ba0, Ene); |
---|
507 | pl[2] = Poli(aw,bw,cw,Ene); |
---|
508 | pl[3] = Poli(axc,bxc,cxc,Ene); |
---|
509 | |
---|
510 | //G4cout << "PL < 50."<< pl[0] << " " << pl[1] << " " << pl[2] << " " <<pl[3] << " " << G4endl; |
---|
511 | //G4cout << "ENCU "<< xe << G4endl; |
---|
512 | n1 = Fintlor(pl,pi) - Fintlor(pl,xe); |
---|
513 | |
---|
514 | } |
---|
515 | |
---|
516 | |
---|
517 | G4double n=0.; |
---|
518 | n = n1+n2; |
---|
519 | |
---|
520 | G4double c1 = 0.; |
---|
521 | c1 = Glor(pl, xe); |
---|
522 | |
---|
523 | G4double xm = 0.; |
---|
524 | xm = Flor(pl,pl[3])*Glor(pl,pl[3]); |
---|
525 | |
---|
526 | G4double r1,r2,r3; |
---|
527 | G4double xco=0.; |
---|
528 | |
---|
529 | if (Ene>=50.) |
---|
530 | { |
---|
531 | r1= G4UniformRand(); |
---|
532 | if( r1>=n2/n) |
---|
533 | { |
---|
534 | do |
---|
535 | { |
---|
536 | r2 = G4UniformRand(); |
---|
537 | value = Finvlor(pl,xe,r2); |
---|
538 | xco = Glor(pl,value)/c1; |
---|
539 | r3 = G4UniformRand(); |
---|
540 | } while(r3>=xco); |
---|
541 | } |
---|
542 | else |
---|
543 | { |
---|
544 | value = Finvtan(pt,n,r1); |
---|
545 | } |
---|
546 | } |
---|
547 | else |
---|
548 | { |
---|
549 | do |
---|
550 | { |
---|
551 | r2 = G4UniformRand(); |
---|
552 | value = Finvlor(pl,xe,r2); |
---|
553 | xco = Glor(pl,value)/c1; |
---|
554 | r3 = G4UniformRand(); |
---|
555 | } while(r3>=xco); |
---|
556 | } |
---|
557 | |
---|
558 | // G4cout << "PHI = " <<value << G4endl; |
---|
559 | return value; |
---|
560 | } |
---|
561 | G4double G4LivermorePolarizedGammaConversionModel::SetPsi(G4double Energy, G4double Phi) |
---|
562 | { |
---|
563 | |
---|
564 | G4double value = 0.; |
---|
565 | G4double Ene = Energy/MeV; |
---|
566 | |
---|
567 | G4double p0l[4]; |
---|
568 | G4double ppml[4]; |
---|
569 | G4double p0t[2]; |
---|
570 | G4double ppmt[2]; |
---|
571 | |
---|
572 | G4double xi = 0.; |
---|
573 | G4double xe0 = 0.; |
---|
574 | G4double xepm = 0.; |
---|
575 | |
---|
576 | if (Ene>=50.) |
---|
577 | { |
---|
578 | const G4double ay00 = 3.4, by00 = 9.8, aa00 = 1.34, ba00 = 5.3; |
---|
579 | const G4double aw0 = 0.014, bw0 = 9.7, cw0 = -2.E4; |
---|
580 | const G4double axc0 = 3.1423, bxc0 = -2.35, cxc0 = 0.; |
---|
581 | const G4double ay0p = 1.53, by0p = 3.2, aap = 0.67, bap = 8.5E-3; |
---|
582 | const G4double awp = 6.9E-3, bwp = 12.6, cwp = -3.8E4; |
---|
583 | const G4double axcp = 2.8E-3,bxcp = -3.133; |
---|
584 | const G4double abf0 = 3.1213, bbf0 = 2.61; |
---|
585 | const G4double abfpm = 3.1231, bbfpm = 2.84; |
---|
586 | |
---|
587 | p0l[0] = Fln(ay00, by00, Ene); |
---|
588 | p0l[1] = Fln(aa00, ba00, Ene); |
---|
589 | p0l[2] = Poli(aw0, bw0, cw0, Ene); |
---|
590 | p0l[3] = Poli(axc0, bxc0, cxc0, Ene); |
---|
591 | |
---|
592 | ppml[0] = Fln(ay0p, by0p, Ene); |
---|
593 | ppml[1] = aap + bap*(Ene); |
---|
594 | ppml[2] = Poli(awp, bwp, cwp, Ene); |
---|
595 | ppml[3] = Fln(axcp,bxcp,Ene); |
---|
596 | |
---|
597 | p0t[0] = -0.81; |
---|
598 | p0t[1] = abf0 + bbf0/Ene; |
---|
599 | ppmt[0] = -0.6; |
---|
600 | ppmt[1] = abfpm + bbfpm/Ene; |
---|
601 | |
---|
602 | //G4cout << "P0L > 50"<< p0l[0] << " " << p0l[1] << " " << p0l[2] << " " <<p0l[3] << " " << G4endl; |
---|
603 | //G4cout << "PPML > 50"<< ppml[0] << " " << ppml[1] << " " << ppml[2] << " " <<ppml[3] << " " << G4endl; |
---|
604 | |
---|
605 | xi = 3.0; |
---|
606 | xe0 = Encu(p0l, p0t, xi); |
---|
607 | //G4cout << "ENCU1 "<< xe0 << G4endl; |
---|
608 | xepm = Encu(ppml, ppmt, xi); |
---|
609 | |
---|
610 | |
---|
611 | //G4cout << "ENCU2 "<< xepm << G4endl; |
---|
612 | |
---|
613 | } |
---|
614 | else |
---|
615 | { |
---|
616 | const G4double ay00 = 2.82, by00 = 6.35; |
---|
617 | const G4double aa00 = -1.75, ba00 = 0.25; |
---|
618 | |
---|
619 | const G4double aw0 = 0.028, bw0 = 5., cw0 = -50.; |
---|
620 | const G4double axc0 = 3.14213, bxc0 = -2.3, cxc0 = 5.7; |
---|
621 | const G4double ay0p = 1.56, by0p = 3.6; |
---|
622 | const G4double aap = 0.86, bap = 8.3E-3; |
---|
623 | const G4double awp = 0.022, bwp = 7.4, cwp = -51.; |
---|
624 | const G4double xcp = 3.1486; |
---|
625 | |
---|
626 | p0l[0] = Fln(ay00, by00, Ene); |
---|
627 | p0l[1] = aa00+pow(Ene, ba00); |
---|
628 | p0l[2] = Poli(aw0, bw0, cw0, Ene); |
---|
629 | p0l[3] = Poli(axc0, bxc0, cxc0, Ene); |
---|
630 | ppml[0] = Fln(ay0p, by0p, Ene); |
---|
631 | ppml[1] = aap + bap*(Ene); |
---|
632 | ppml[2] = Poli(awp, bwp, cwp, Ene); |
---|
633 | ppml[3] = xcp; |
---|
634 | |
---|
635 | } |
---|
636 | |
---|
637 | |
---|
638 | |
---|
639 | G4double a,b=0.; |
---|
640 | |
---|
641 | if (Ene>=50.) |
---|
642 | { |
---|
643 | if (Phi>xepm) |
---|
644 | { |
---|
645 | b = (ppml[0]+2*ppml[1]*ppml[2]*Flor(ppml,Phi)); |
---|
646 | } |
---|
647 | else |
---|
648 | { |
---|
649 | b = Ftan(ppmt,Phi); |
---|
650 | } |
---|
651 | if (Phi>xe0) |
---|
652 | { |
---|
653 | a = (p0l[0]+2*p0l[1]*p0l[2]*Flor(p0l,Phi)); |
---|
654 | } |
---|
655 | else |
---|
656 | { |
---|
657 | a = Ftan(p0t,Phi); |
---|
658 | } |
---|
659 | } |
---|
660 | else |
---|
661 | { |
---|
662 | b = (ppml[0]+2*ppml[1]*ppml[2]*Flor(ppml,Phi)); |
---|
663 | a = (p0l[0]+2*p0l[1]*p0l[2]*Flor(p0l,Phi)); |
---|
664 | } |
---|
665 | G4double nr =0.; |
---|
666 | |
---|
667 | if (b>a) |
---|
668 | { |
---|
669 | nr = 1./b; |
---|
670 | } |
---|
671 | else |
---|
672 | { |
---|
673 | nr = 1./a; |
---|
674 | } |
---|
675 | |
---|
676 | G4double r1,r2=0.; |
---|
677 | G4double r3 =-1.; |
---|
678 | do |
---|
679 | { |
---|
680 | r1 = G4UniformRand(); |
---|
681 | r2 = G4UniformRand(); |
---|
682 | value = r2*pi; |
---|
683 | r3 = nr*(a*cos(value)*cos(value) + b*sin(value)*sin(value)); |
---|
684 | }while(r1>r3); |
---|
685 | |
---|
686 | return value; |
---|
687 | } |
---|
688 | |
---|
689 | |
---|
690 | G4double G4LivermorePolarizedGammaConversionModel::Poli |
---|
691 | (G4double a, G4double b, G4double c, G4double x) |
---|
692 | { |
---|
693 | G4double value=0.; |
---|
694 | if(x>0.) |
---|
695 | { |
---|
696 | value =(a + b/x + c/(x*x*x)); |
---|
697 | } |
---|
698 | else |
---|
699 | { |
---|
700 | //G4cout << "ERROR in Poli! " << G4endl; |
---|
701 | } |
---|
702 | return value; |
---|
703 | } |
---|
704 | G4double G4LivermorePolarizedGammaConversionModel::Fln |
---|
705 | (G4double a, G4double b, G4double x) |
---|
706 | { |
---|
707 | G4double value=0.; |
---|
708 | if(x>0.) |
---|
709 | { |
---|
710 | value =(a*log(x)-b); |
---|
711 | } |
---|
712 | else |
---|
713 | { |
---|
714 | //G4cout << "ERROR in Fln! " << G4endl; |
---|
715 | } |
---|
716 | return value; |
---|
717 | } |
---|
718 | |
---|
719 | |
---|
720 | G4double G4LivermorePolarizedGammaConversionModel::Encu |
---|
721 | (G4double* p_p1, G4double* p_p2, G4double x) |
---|
722 | { |
---|
723 | G4double value=0.; |
---|
724 | G4int i=0; |
---|
725 | G4double fx = 1.; |
---|
726 | |
---|
727 | do |
---|
728 | { |
---|
729 | x -= (Flor(p_p1, x)*Glor(p_p1,x) - Ftan(p_p2, x))/ |
---|
730 | (Fdlor(p_p1,x) - Fdtan(p_p2,x)); |
---|
731 | fx = Flor(p_p1,x)*Glor(p_p1,x) - Ftan(p_p2, x); |
---|
732 | i += 1; |
---|
733 | //G4cout << abs(fx) << " " << i << " " << x << "dentro ENCU " << G4endl; |
---|
734 | } while( (i<100) && (abs(fx) > 1e-6)) ; |
---|
735 | |
---|
736 | if (i>100||x>pi) x = 3.0; |
---|
737 | value = x; |
---|
738 | |
---|
739 | if (value<0.) value=0.; |
---|
740 | |
---|
741 | return value; |
---|
742 | } |
---|
743 | |
---|
744 | |
---|
745 | |
---|
746 | |
---|
747 | G4double G4LivermorePolarizedGammaConversionModel::Flor(G4double* p_p1, G4double x) |
---|
748 | { |
---|
749 | G4double value =0.; |
---|
750 | // G4double y0 = p_p1[0]; |
---|
751 | // G4double A = p_p1[1]; |
---|
752 | G4double w = p_p1[2]; |
---|
753 | G4double xc = p_p1[3]; |
---|
754 | |
---|
755 | value = 1./(pi*(w*w + 4.*(x-xc)*(x-xc))); |
---|
756 | return value; |
---|
757 | } |
---|
758 | |
---|
759 | G4double G4LivermorePolarizedGammaConversionModel::Glor(G4double* p_p1, G4double x) |
---|
760 | { |
---|
761 | G4double value =0.; |
---|
762 | G4double y0 = p_p1[0]; |
---|
763 | G4double A = p_p1[1]; |
---|
764 | G4double w = p_p1[2]; |
---|
765 | G4double xc = p_p1[3]; |
---|
766 | |
---|
767 | value = (y0 *pi*(w*w + 4.*(x-xc)*(x-xc)) + 2.*A*w); |
---|
768 | return value; |
---|
769 | } |
---|
770 | |
---|
771 | G4double G4LivermorePolarizedGammaConversionModel::Fdlor(G4double* p_p1, G4double x) |
---|
772 | { |
---|
773 | G4double value =0.; |
---|
774 | //G4double y0 = p_p1[0]; |
---|
775 | G4double A = p_p1[1]; |
---|
776 | G4double w = p_p1[2]; |
---|
777 | G4double xc = p_p1[3]; |
---|
778 | |
---|
779 | value = (-16.*A*w*(x-xc))/ |
---|
780 | (pi*(w*w+4.*(x-xc)*(x-xc))*(w*w+4.*(x-xc)*(x-xc))); |
---|
781 | return value; |
---|
782 | } |
---|
783 | |
---|
784 | |
---|
785 | G4double G4LivermorePolarizedGammaConversionModel::Fintlor(G4double* p_p1, G4double x) |
---|
786 | { |
---|
787 | G4double value =0.; |
---|
788 | G4double y0 = p_p1[0]; |
---|
789 | G4double A = p_p1[1]; |
---|
790 | G4double w = p_p1[2]; |
---|
791 | G4double xc = p_p1[3]; |
---|
792 | |
---|
793 | value = y0*x + A*atan( 2*(x-xc)/w) / pi; |
---|
794 | return value; |
---|
795 | } |
---|
796 | |
---|
797 | |
---|
798 | G4double G4LivermorePolarizedGammaConversionModel::Finvlor(G4double* p_p1, G4double x, G4double r) |
---|
799 | { |
---|
800 | G4double value = 0.; |
---|
801 | G4double nor = 0.; |
---|
802 | //G4double y0 = p_p1[0]; |
---|
803 | // G4double A = p_p1[1]; |
---|
804 | G4double w = p_p1[2]; |
---|
805 | G4double xc = p_p1[3]; |
---|
806 | |
---|
807 | nor = atan(2.*(pi-xc)/w)/(2.*pi*w) - atan(2.*(x-xc)/w)/(2.*pi*w); |
---|
808 | value = xc - (w/2.)*tan(-2.*r*nor*pi*w+atan(2*(xc-x)/w)); |
---|
809 | |
---|
810 | return value; |
---|
811 | } |
---|
812 | |
---|
813 | G4double G4LivermorePolarizedGammaConversionModel::Ftan(G4double* p_p1, G4double x) |
---|
814 | { |
---|
815 | G4double value =0.; |
---|
816 | G4double a = p_p1[0]; |
---|
817 | G4double b = p_p1[1]; |
---|
818 | |
---|
819 | value = a /(x-b); |
---|
820 | return value; |
---|
821 | } |
---|
822 | |
---|
823 | |
---|
824 | G4double G4LivermorePolarizedGammaConversionModel::Fdtan(G4double* p_p1, G4double x) |
---|
825 | { |
---|
826 | G4double value =0.; |
---|
827 | G4double a = p_p1[0]; |
---|
828 | G4double b = p_p1[1]; |
---|
829 | |
---|
830 | value = -1.*a / ((x-b)*(x-b)); |
---|
831 | return value; |
---|
832 | } |
---|
833 | |
---|
834 | |
---|
835 | G4double G4LivermorePolarizedGammaConversionModel::Finttan(G4double* p_p1, G4double x) |
---|
836 | { |
---|
837 | G4double value =0.; |
---|
838 | G4double a = p_p1[0]; |
---|
839 | G4double b = p_p1[1]; |
---|
840 | |
---|
841 | |
---|
842 | value = a*log(b-x); |
---|
843 | return value; |
---|
844 | } |
---|
845 | |
---|
846 | G4double G4LivermorePolarizedGammaConversionModel::Finvtan(G4double* p_p1, G4double cnor, G4double r) |
---|
847 | { |
---|
848 | G4double value =0.; |
---|
849 | G4double a = p_p1[0]; |
---|
850 | G4double b = p_p1[1]; |
---|
851 | |
---|
852 | value = b*(1-exp(r*cnor/a)); |
---|
853 | |
---|
854 | return value; |
---|
855 | } |
---|
856 | |
---|
857 | |
---|
858 | |
---|
859 | |
---|
860 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
---|
861 | |
---|
862 | G4ThreeVector G4LivermorePolarizedGammaConversionModel::SetPerpendicularVector(G4ThreeVector& a) |
---|
863 | { |
---|
864 | G4double dx = a.x(); |
---|
865 | G4double dy = a.y(); |
---|
866 | G4double dz = a.z(); |
---|
867 | G4double x = dx < 0.0 ? -dx : dx; |
---|
868 | G4double y = dy < 0.0 ? -dy : dy; |
---|
869 | G4double z = dz < 0.0 ? -dz : dz; |
---|
870 | if (x < y) { |
---|
871 | return x < z ? G4ThreeVector(-dy,dx,0) : G4ThreeVector(0,-dz,dy); |
---|
872 | }else{ |
---|
873 | return y < z ? G4ThreeVector(dz,0,-dx) : G4ThreeVector(-dy,dx,0); |
---|
874 | } |
---|
875 | } |
---|
876 | |
---|
877 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
---|
878 | |
---|
879 | G4ThreeVector G4LivermorePolarizedGammaConversionModel::GetRandomPolarization(G4ThreeVector& direction0) |
---|
880 | { |
---|
881 | G4ThreeVector d0 = direction0.unit(); |
---|
882 | G4ThreeVector a1 = SetPerpendicularVector(d0); //different orthogonal |
---|
883 | G4ThreeVector a0 = a1.unit(); // unit vector |
---|
884 | |
---|
885 | G4double rand1 = G4UniformRand(); |
---|
886 | |
---|
887 | G4double angle = twopi*rand1; // random polar angle |
---|
888 | G4ThreeVector b0 = d0.cross(a0); // cross product |
---|
889 | |
---|
890 | G4ThreeVector c; |
---|
891 | |
---|
892 | c.setX(std::cos(angle)*(a0.x())+std::sin(angle)*b0.x()); |
---|
893 | c.setY(std::cos(angle)*(a0.y())+std::sin(angle)*b0.y()); |
---|
894 | c.setZ(std::cos(angle)*(a0.z())+std::sin(angle)*b0.z()); |
---|
895 | |
---|
896 | G4ThreeVector c0 = c.unit(); |
---|
897 | |
---|
898 | return c0; |
---|
899 | |
---|
900 | } |
---|
901 | |
---|
902 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
---|
903 | |
---|
904 | G4ThreeVector G4LivermorePolarizedGammaConversionModel::GetPerpendicularPolarization |
---|
905 | (const G4ThreeVector& gammaDirection, const G4ThreeVector& gammaPolarization) const |
---|
906 | { |
---|
907 | |
---|
908 | // |
---|
909 | // The polarization of a photon is always perpendicular to its momentum direction. |
---|
910 | // Therefore this function removes those vector component of gammaPolarization, which |
---|
911 | // points in direction of gammaDirection |
---|
912 | // |
---|
913 | // Mathematically we search the projection of the vector a on the plane E, where n is the |
---|
914 | // plains normal vector. |
---|
915 | // The basic equation can be found in each geometry book (e.g. Bronstein): |
---|
916 | // p = a - (a o n)/(n o n)*n |
---|
917 | |
---|
918 | return gammaPolarization - gammaPolarization.dot(gammaDirection)/gammaDirection.dot(gammaDirection) * gammaDirection; |
---|
919 | } |
---|
920 | |
---|
921 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
---|
922 | |
---|
923 | |
---|
924 | void G4LivermorePolarizedGammaConversionModel::SystemOfRefChange |
---|
925 | (G4ThreeVector& direction0,G4ThreeVector& direction1, |
---|
926 | G4ThreeVector& polarization0) |
---|
927 | { |
---|
928 | // direction0 is the original photon direction ---> z |
---|
929 | // polarization0 is the original photon polarization ---> x |
---|
930 | // need to specify y axis in the real reference frame ---> y |
---|
931 | G4ThreeVector Axis_Z0 = direction0.unit(); |
---|
932 | G4ThreeVector Axis_X0 = polarization0.unit(); |
---|
933 | G4ThreeVector Axis_Y0 = (Axis_Z0.cross(Axis_X0)).unit(); // to be confirmed; |
---|
934 | |
---|
935 | G4double direction_x = direction1.getX(); |
---|
936 | G4double direction_y = direction1.getY(); |
---|
937 | G4double direction_z = direction1.getZ(); |
---|
938 | |
---|
939 | direction1 = (direction_x*Axis_X0 + direction_y*Axis_Y0 + direction_z*Axis_Z0).unit(); |
---|
940 | |
---|
941 | } |
---|
942 | |
---|
943 | |
---|
944 | |
---|
945 | |
---|