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2 | // ******************************************************************** |
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3 | // * License and Disclaimer * |
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9 | // * include a list of copyright holders. * |
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15 | // * use. Please see the license in the file LICENSE and URL above * |
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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 | // $Id: G4MuMscModel.cc,v 1.6 2007/11/11 17:40:48 vnivanch Exp $ |
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27 | // GEANT4 tag $Name: geant4-09-01-patch-02 $ |
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28 | // |
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29 | // ------------------------------------------------------------------- |
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30 | // |
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31 | // GEANT4 Class file |
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32 | // |
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33 | // |
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34 | // File name: G4MuMscModel |
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35 | // |
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36 | // Author: Laszlo Mu |
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37 | // |
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38 | // Creation date: 03.03.2001 |
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39 | // |
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40 | // Modifications: |
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41 | // |
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42 | // 27-03-03 Move model part from G4MultipleScattering80 (V.Ivanchenko) |
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43 | // |
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44 | |
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45 | // Class Description: |
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46 | // |
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47 | // Implementation of the model of multiple scattering based on |
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48 | // H.W.Lewis Phys Rev 78 (1950) 526 and others |
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49 | |
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50 | // ------------------------------------------------------------------- |
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51 | // |
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52 | |
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53 | |
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54 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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55 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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56 | |
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57 | #include "G4MuMscModel.hh" |
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58 | #include "Randomize.hh" |
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59 | #include "G4Electron.hh" |
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60 | #include "G4LossTableManager.hh" |
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61 | #include "G4ParticleChangeForMSC.hh" |
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62 | #include "G4TransportationManager.hh" |
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63 | #include "G4SafetyHelper.hh" |
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64 | #include "G4eCoulombScatteringModel.hh" |
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65 | #include "G4PhysicsTableHelper.hh" |
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66 | #include "G4ElementVector.hh" |
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67 | #include "G4ProductionCutsTable.hh" |
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68 | #include "G4PhysicsLogVector.hh" |
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69 | //#include "G4Poisson.hh" |
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70 | |
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71 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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72 | |
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73 | using namespace std; |
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74 | |
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75 | G4MuMscModel::G4MuMscModel(G4double frange, |
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76 | G4double thetaMax, |
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77 | G4double tMax, |
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78 | const G4String& nam) |
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79 | : G4eCoulombScatteringModel(0.0,thetaMax,false,tMax,nam), |
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80 | theLambdaTable(0), |
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81 | theLambda2Table(0), |
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82 | dtrl(0.05), |
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83 | facrange(frange), |
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84 | thetaLimit(thetaMax), |
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85 | numlimit(0.2), |
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86 | lowBinEnergy(keV), |
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87 | highBinEnergy(PeV), |
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88 | nbins(60), |
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89 | nwarnings(0), |
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90 | nwarnlimit(50), |
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91 | currentCouple(0), |
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92 | isInitialized(false), |
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93 | buildTables(true), |
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94 | newrun(true), |
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95 | inside(false) |
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96 | { |
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97 | invsqrt12 = 1./sqrt(12.); |
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98 | tlimitminfix = 1.e-6*mm; |
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99 | theManager = G4LossTableManager::Instance(); |
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100 | } |
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101 | |
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102 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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103 | |
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104 | G4MuMscModel::~G4MuMscModel() |
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105 | {} |
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106 | |
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107 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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108 | |
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109 | void G4MuMscModel::Initialise(const G4ParticleDefinition* p, |
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110 | const G4DataVector& cuts) |
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111 | { |
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112 | SetupParticle(p); |
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113 | newrun = true; |
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114 | xSection = currentRange = targetZ = ecut = tkin = 0.0; |
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115 | // set values of some data members |
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116 | if(!isInitialized) { |
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117 | isInitialized = true; |
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118 | if(p->GetParticleName() == "GenericIon") buildTables = false; |
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119 | |
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120 | if (pParticleChange) |
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121 | fParticleChange = reinterpret_cast<G4ParticleChangeForMSC*>(pParticleChange); |
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122 | else |
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123 | fParticleChange = new G4ParticleChangeForMSC(); |
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124 | |
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125 | safetyHelper = G4TransportationManager::GetTransportationManager() |
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126 | ->GetSafetyHelper(); |
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127 | safetyHelper->InitialiseHelper(); |
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128 | } |
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129 | G4eCoulombScatteringModel::Initialise(p, cuts); |
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130 | currentCuts = &cuts; |
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131 | if(buildTables) |
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132 | theLambda2Table = G4PhysicsTableHelper::PreparePhysicsTable(theLambda2Table); |
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133 | } |
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134 | |
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135 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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136 | |
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137 | void G4MuMscModel::BuildTables() |
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138 | { |
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139 | //G4cout << "G4MuMscModel::BuildTables flags newrun= " << newrun |
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140 | // << " buildTables= " << buildTables << G4endl; |
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141 | newrun = false; |
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142 | if(!buildTables) return; |
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143 | |
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144 | // Access to materials |
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145 | const G4ProductionCutsTable* theCoupleTable= |
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146 | G4ProductionCutsTable::GetProductionCutsTable(); |
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147 | size_t numOfCouples = theCoupleTable->GetTableSize(); |
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148 | G4double e, s, cut; |
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149 | |
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150 | for(size_t i=0; i<numOfCouples; i++) { |
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151 | |
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152 | if (theLambda2Table->GetFlag(i)) { |
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153 | |
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154 | // create physics vector and fill it |
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155 | DefineMaterial(theCoupleTable->GetMaterialCutsCouple(i)); |
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156 | cut = (*currentCuts)[currentMaterialIndex]; |
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157 | G4PhysicsVector* aVector = |
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158 | new G4PhysicsLogVector(lowBinEnergy, highBinEnergy, nbins); |
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159 | for(G4int j=0; j<nbins; j++) { |
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160 | e = aVector->GetLowEdgeEnergy(j); |
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161 | s = ComputeLambda2(e, cut); |
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162 | //G4cout << j << " " << currentCouple->GetMaterial()->GetName() |
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163 | // << " e(MeV)= " << e << " cut(MeV)= " << cut |
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164 | // << " L2= " << s << G4endl; |
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165 | aVector->PutValue(j, s); |
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166 | } |
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167 | |
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168 | G4PhysicsTableHelper::SetPhysicsVector(theLambda2Table, i, aVector); |
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169 | } |
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170 | } |
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171 | } |
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172 | |
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173 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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174 | |
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175 | G4double G4MuMscModel::ComputeCrossSectionPerAtom( |
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176 | const G4ParticleDefinition* p, |
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177 | G4double kinEnergy, |
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178 | G4double Z, G4double A, |
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179 | G4double cutEnergy, G4double) |
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180 | { |
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181 | if(p == particle && kinEnergy == tkin && Z == targetZ && |
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182 | cutEnergy == ecut) return xSection; |
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183 | ecut = cutEnergy; |
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184 | xSection = 0.0; |
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185 | SetupParticle(p); |
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186 | G4double ekin = std::max(keV, kinEnergy); |
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187 | SetupTarget(Z, A, ekin); |
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188 | |
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189 | G4double tmax = tkin; |
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190 | if(p == theElectron) tmax *= 0.5; |
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191 | else if(p != thePositron) { |
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192 | G4double ratio = electron_mass_c2/mass; |
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193 | tmax = 2.0*mom2/ |
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194 | (electron_mass_c2*(1.0 + ratio*(tkin/mass + 1.0) + ratio*ratio)); |
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195 | } |
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196 | G4double t = std::min(cutEnergy, tmax); |
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197 | G4double mom21 = t*(t + 2.0*electron_mass_c2); |
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198 | t = tkin - t; |
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199 | G4double mom22 = t*(t + 2.0*mass); |
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200 | cosTetMaxElec = (mom2 + mom22 - mom21)*0.5/sqrt(mom2*mom22); |
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201 | if(cosTetMaxElec < cosTetMaxNuc) cosTetMaxElec = cosTetMaxNuc; |
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202 | |
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203 | if(cosTetMaxElec < 1.0) { |
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204 | G4double x2 = screenZ/(1.0 - cosTetMaxElec + screenZ); |
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205 | xSection += (x2 - 1.0 - log(x2))/Z; |
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206 | } |
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207 | // G4cout << "cut= " << ecut << " e= " << tkin << " croosE= " |
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208 | // << xSection/barn << G4endl; |
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209 | |
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210 | if(cosTetMaxNuc < 1.0) { |
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211 | G4double x1 = screenZ*formfactA; |
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212 | G4double x2 = 1.0 - cosTetMaxNuc + screenZ; |
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213 | G4double x3 = 1.0 - x1; |
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214 | G4double x4 = 1.0/(formfactA*x2 + x3); |
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215 | G4double x5 = screenZ/x2; |
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216 | xSection += ((1.0 - 2.0*x1/x3)*log(x4/x5) - 1.0 + |
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217 | x5 - (1.0 - 4.0*x1)*(1.0 - x4))/(x3*x3); |
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218 | } |
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219 | xSection *= coeff*Z*Z*chargeSquare*invbeta2/mom2; |
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220 | // G4cout << " croosE= " << xSection/barn << " screenZ= " |
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221 | // << screenZ << " formF= " << formfactA << G4endl; |
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222 | return xSection; |
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223 | } |
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224 | |
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225 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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226 | |
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227 | G4double G4MuMscModel::ComputeLambda2(G4double kinEnergy, |
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228 | G4double cutEnergy) |
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229 | { |
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230 | G4double res = 0.0; |
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231 | SetupParticle(particle); |
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232 | G4double ekin = std::max(keV, kinEnergy); |
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233 | |
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234 | const G4Material* mat = currentCouple->GetMaterial(); |
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235 | const G4ElementVector* theElementVector = mat->GetElementVector(); |
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236 | const G4double* theAtomNumDensityVector = mat->GetVecNbOfAtomsPerVolume(); |
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237 | size_t nelm = mat->GetNumberOfElements(); |
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238 | |
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239 | SetupKinematic(ekin); |
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240 | |
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241 | G4double tmax = tkin; |
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242 | if(particle == theElectron) tmax *= 0.5; |
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243 | else if(particle != thePositron) { |
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244 | G4double ratio = electron_mass_c2/mass; |
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245 | tmax = 2.0*mom2/ |
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246 | (electron_mass_c2*(1.0 + ratio*(tkin/mass + 1.0) + ratio*ratio)); |
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247 | } |
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248 | G4double t = std::min(cutEnergy, tmax); |
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249 | G4double mom21 = t*(t + 2.0*electron_mass_c2); |
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250 | t = tkin - t; |
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251 | G4double mom22 = t*(t + 2.0*mass); |
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252 | cosTetMaxElec = (mom2 + mom22 - mom21)*0.5/sqrt(mom2*mom22); |
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253 | if(cosTetMaxElec < 0.0) cosTetMaxElec = 0.0; |
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254 | |
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255 | G4double x, x1, x2, y; |
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256 | |
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257 | for (size_t i=0; i<nelm; i++) { |
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258 | const G4Element* elm = (*theElementVector)[i]; |
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259 | G4double Z = elm->GetZ(); |
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260 | SetupTarget(Z, elm->GetN(), tkin); |
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261 | G4double s = 0.0; |
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262 | G4double costm = cosTetMaxElec; |
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263 | if(costm < cosTetMaxNuc) costm = cosTetMaxNuc; |
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264 | if(costm < 1.0) { |
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265 | x = 1.0 - costm + screenZ; |
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266 | y = (x - screenZ*(screenZ/x + 2.0*log(x/screenZ)))/Z; |
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267 | if(y < 0.0) { |
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268 | nwarnings++; |
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269 | if(nwarnings < nwarnlimit) |
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270 | G4cout << "Electron scattering <0 for L2 " << y << G4endl; |
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271 | y = 0.0; |
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272 | } |
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273 | s += y; |
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274 | } |
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275 | // G4cout << "cut= " << cut << " e= " << tkin << " croosE= " |
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276 | // << xSection/barn << G4endl; |
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277 | |
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278 | // limit main integral because of nuclear size effect |
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279 | |
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280 | if(cosTetMaxNuc < 1.0) { |
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281 | x1 = screenZ*formfactA; |
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282 | x2 = 1.0 - cosTetMaxNuc + screenZ; |
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283 | G4double x3 = 1.0 - x1; |
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284 | G4double f = 1.0/formfactA; |
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285 | G4double d = f - screenZ; |
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286 | G4double x4 = f/(x2 + d); |
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287 | G4double x5 = screenZ/x2; |
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288 | y = (screenZ*(1.0 - x5) + (d*d - screenZ*(2.0*d - 3.0*screenZ))*(1.0 - x4)/f - |
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289 | 2.0*screenZ*f*log(x4/x5)/d)/(x3*x3); |
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290 | if(y < 0.0) { |
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291 | nwarnings++; |
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292 | if(nwarnings < nwarnlimit) |
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293 | G4cout << "Nuclear scattering <0 for L2 " << y << G4endl; |
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294 | y = 0.0; |
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295 | } |
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296 | s += y; |
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297 | } |
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298 | |
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299 | res += Z*Z*s*theAtomNumDensityVector[i]; |
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300 | } |
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301 | res *= 0.25*coeff*chargeSquare*invbeta2/mom2; |
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302 | // G4cout << " croosE= " << xSection/barn << " screenZ= " |
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303 | // << screenZ << " formF= " << formfactA << G4endl; |
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304 | return res; |
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305 | } |
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306 | |
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307 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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308 | |
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309 | G4double G4MuMscModel::ComputeTruePathLengthLimit( |
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310 | const G4Track& track, |
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311 | G4PhysicsTable* theTable, |
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312 | G4double currentMinimalStep) |
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313 | { |
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314 | G4double tlimit = currentMinimalStep; |
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315 | const G4DynamicParticle* dp = track.GetDynamicParticle(); |
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316 | |
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317 | // initialisation for 1st step |
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318 | if(track.GetCurrentStepNumber() == 1) { |
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319 | inside = false; |
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320 | SetupParticle(dp->GetDefinition()); |
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321 | theLambdaTable = theTable; |
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322 | if(newrun && buildTables) BuildTables(); |
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323 | } |
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324 | |
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325 | // initialisation for each step |
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326 | preKinEnergy = dp->GetKineticEnergy(); |
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327 | DefineMaterial(track.GetMaterialCutsCouple()); |
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328 | lambda0 = GetLambda(preKinEnergy); |
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329 | currentRange = |
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330 | theManager->GetRangeFromRestricteDEDX(particle,preKinEnergy,currentCouple); |
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331 | |
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332 | // extra check for abnormal situation |
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333 | // this check needed to run MSC with eIoni and eBrem inactivated |
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334 | if(tlimit > currentRange) tlimit = currentRange; |
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335 | |
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336 | // stop here if small range particle |
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337 | if(inside) return tlimit; |
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338 | |
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339 | // pre step |
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340 | G4StepPoint* sp = track.GetStep()->GetPreStepPoint(); |
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341 | G4StepStatus stepStatus = sp->GetStepStatus(); |
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342 | G4double presafety = sp->GetSafety(); |
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343 | |
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344 | // compute presafety again if presafety <= 0 and no boundary |
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345 | // i.e. when it is needed for optimization purposes |
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346 | if(stepStatus != fGeomBoundary && presafety < tlimitminfix) |
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347 | presafety = safetyHelper->ComputeSafety(sp->GetPosition()); |
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348 | |
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349 | // G4cout << "G4MuMscModel::ComputeTruePathLengthLimit tlimit= " |
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350 | // <<tlimit<<" safety= " << presafety |
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351 | // << " range= " <<currentRange<<G4endl; |
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352 | |
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353 | // far from geometry boundary |
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354 | if(currentRange < presafety) { |
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355 | inside = true; |
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356 | |
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357 | // limit mean scattering angle |
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358 | } else { |
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359 | tlimit = std::min(facrange*lambda0, tlimit); |
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360 | } |
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361 | /* |
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362 | G4cout << particle->GetParticleName() << " e= " << preKinEnergy |
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363 | << " L0= " << lambda0 << " R= " << currentRange |
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364 | << "tlimit= " << tlimit |
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365 | << " currentMinimalStep= " << currentMinimalStep << G4endl; |
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366 | */ |
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367 | return tlimit; |
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368 | } |
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369 | |
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370 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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371 | |
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372 | G4double G4MuMscModel::ComputeGeomPathLength(G4double truelength) |
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373 | { |
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374 | tPathLength = truelength; |
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375 | zPathLength = tPathLength; |
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376 | |
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377 | G4double tau = tPathLength/lambda0; |
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378 | lambdaeff = lambda0; |
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379 | //G4cout << "ComputeGeomPathLength: tLength= " << tPathLength |
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380 | // << " lambda0= " << lambda0 << " tau= " << tau << G4endl; |
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381 | // small step |
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382 | if(tau < numlimit) { |
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383 | par1 = -1. ; |
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384 | par2 = par3 = 0. ; |
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385 | zPathLength *= (1.0 - 0.5*tau + tau*tau/6.0); |
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386 | |
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387 | // medium step |
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388 | } else if(tPathLength < currentRange*dtrl) { |
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389 | zPathLength = lambda0*(1.0 - exp(-tau)); |
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390 | |
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391 | } else if(tkin < mass) { |
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392 | |
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393 | par1 = 1./currentRange; |
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394 | par2 = 1./(par1*lambda0); |
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395 | par3 = 1.+ par2; |
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396 | lambdaeff = 1.0/(par1*par3); |
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397 | G4double x = tPathLength/currentRange; |
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398 | G4double x1; |
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399 | if(x < numlimit) x1 = x*(1.0 - 0.5*x + x*x/3.0); |
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400 | else x1 = log(1.0 - x); |
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401 | zPathLength = lambdaeff*(1.-exp(par3*x1)); |
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402 | |
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403 | } else { |
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404 | |
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405 | G4double T1 = theManager->GetEnergy(particle, |
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406 | currentRange-tPathLength, |
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407 | currentCouple); |
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408 | G4double lambda1 = GetLambda(T1); |
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409 | |
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410 | par1 = (lambda0-lambda1)/(lambda0*tPathLength) ; |
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411 | par2 = 1./(par1*lambda0) ; |
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412 | par3 = 1.+ par2 ; |
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413 | lambdaeff = 1.0/(par1*par3); |
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414 | zPathLength = lambdaeff*(1.-exp(par3*log(lambda1/lambda0))); |
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415 | } |
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416 | |
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417 | // if(zPathLength > lambda0) zPathLength = lambda0; |
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418 | if(zPathLength > tPathLength) zPathLength = tPathLength; |
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419 | |
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420 | return zPathLength; |
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421 | } |
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422 | |
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423 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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424 | |
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425 | G4double G4MuMscModel::ComputeTrueStepLength(G4double geomStepLength) |
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426 | { |
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427 | // step defined other than transportation |
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428 | if(geomStepLength == zPathLength) return tPathLength; |
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429 | |
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430 | tPathLength = geomStepLength; |
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431 | zPathLength = geomStepLength; |
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432 | G4double tau = geomStepLength/lambda0; |
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433 | if(tau < numlimit) { |
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434 | tPathLength *= (1.0 + 0.5*tau - tau*tau/3.0); |
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435 | |
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436 | } else if(par1 < 0.) { |
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437 | tPathLength = -lambda0*log(1.0 - tau); |
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438 | |
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439 | } else { |
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440 | G4double x = par1*par3*geomStepLength; |
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441 | if(x < numlimit) |
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442 | tPathLength = (1.- exp(- x*(1.- 0.5*x + x*x/3.0)/par3))/par1 ; |
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443 | else if (x < 1.0) |
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444 | tPathLength = (1.-exp(log(1.- x)/par3))/par1; |
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445 | else |
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446 | tPathLength = currentRange; |
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447 | } |
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448 | if(tPathLength < geomStepLength) tPathLength = geomStepLength; |
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449 | |
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450 | return tPathLength; |
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451 | } |
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452 | |
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453 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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454 | |
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455 | void G4MuMscModel::SampleScattering(const G4DynamicParticle* dynParticle, |
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456 | G4double safety) |
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457 | { |
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458 | G4double kinEnergy = dynParticle->GetKineticEnergy(); |
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459 | if(kinEnergy == 0.0) return; |
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460 | G4double x1 = 0.5*tPathLength/lambdaeff; |
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461 | |
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462 | /* |
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463 | G4cout << "G4MuMscModel::SampleScattering t(mm)= " << tPathLength |
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464 | << " 1/lambdaeff= " << 1.0/lambdaeff |
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465 | << " matIdx= " << currentMaterialIndex << G4endl; |
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466 | */ |
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467 | /* |
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468 | G4double y1 = 1.0 - x1; |
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469 | G4double x2 = tPathLength*GetLambda2(0.5*(preKinEnergy + kinEnergy)); |
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470 | G4double x3 = (x2 - x1*x1)/(x1*y1); |
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471 | if(x3 <= 0.0 || x3 >= 0.33) { |
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472 | nwarnings++; |
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473 | if(nwarnings < nwarnlimit) |
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474 | G4cout << "G4MuMscModel::SampleScattering: ePre(MeV)= " << preKinEnergy/MeV |
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475 | << " ePost(MeV)= " << kinEnergy/MeV |
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476 | << " <x>= " << x1 << " sqrt(<x^2>)= " << sqrt(x2) |
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477 | << " x3= " << x3 |
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478 | << G4endl; |
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479 | x3 = std::min(1.0/y1,0.16666); |
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480 | } |
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481 | G4double x4 = 0.25*(3.0*x3 + sqrt(x3*(x3 + 8.0)))/(1.0 - x3); |
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482 | */ |
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483 | |
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484 | G4double x = G4UniformRand(); |
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485 | G4double z; |
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486 | |
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487 | //if(x < y1) z = x1*pow(x/y1,x4); |
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488 | //else z = 1.0 - y1*pow((1.0 - x)/x1,x4); |
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489 | |
---|
490 | z = -x1*log(x); |
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491 | |
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492 | G4double cost = 1.0 - 2.0*z; |
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493 | if(cost < -1.0) cost = -1.0; |
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494 | else if(cost > 1.0) cost = 1.0; |
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495 | G4double sint = sqrt((1.0 - cost)*(1.0 + cost)); |
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496 | |
---|
497 | G4double phi = twopi*G4UniformRand(); |
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498 | |
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499 | G4double dirx = sint*cos(phi); |
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500 | G4double diry = sint*sin(phi); |
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501 | |
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502 | // G4cout << "G4MuMscModel::SampleSecondaries: tstep(mm)= " << truestep/mm |
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503 | // << " lambdaeff= " << lambdaeff |
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504 | // << " rms= " << rms << G4endl; |
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505 | |
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506 | G4ThreeVector oldDirection = dynParticle->GetMomentumDirection(); |
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507 | G4ThreeVector newDirection(dirx,diry,cost); |
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508 | newDirection.rotateUz(oldDirection); |
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509 | fParticleChange->ProposeMomentumDirection(newDirection); |
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510 | |
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511 | if (latDisplasment && safety > tlimitminfix) { |
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512 | G4double rms= sqrt(2.0*x1); |
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513 | G4double rx = zPathLength*(0.5*dirx + invsqrt12*G4RandGauss::shoot(0.0,rms)); |
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514 | G4double ry = zPathLength*(0.5*diry + invsqrt12*G4RandGauss::shoot(0.0,rms)); |
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515 | G4double r = sqrt(rx*rx + ry*ry); |
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516 | /* |
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517 | G4cout << "G4MuMscModel::SampleSecondaries: e(MeV)= " << kineticEnergy |
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518 | << " sinTheta= " << sth << " r(mm)= " << r |
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519 | << " trueStep(mm)= " << truestep |
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520 | << " geomStep(mm)= " << zPathLength |
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521 | << G4endl; |
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522 | */ |
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523 | |
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524 | G4ThreeVector latDirection(rx,ry,0.0); |
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525 | latDirection.rotateUz(oldDirection); |
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526 | |
---|
527 | G4ThreeVector Position = *(fParticleChange->GetProposedPosition()); |
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528 | G4double fac = 1.; |
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529 | if(r > safety) { |
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530 | // ******* so safety is computed at boundary too ************ |
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531 | G4double newsafety = safetyHelper->ComputeSafety(Position); |
---|
532 | if(r > newsafety) |
---|
533 | fac = newsafety/r ; |
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534 | } |
---|
535 | |
---|
536 | if(fac > 0.) { |
---|
537 | // compute new endpoint of the Step |
---|
538 | G4ThreeVector newPosition = Position+fac*r*latDirection; |
---|
539 | |
---|
540 | // definitely not on boundary |
---|
541 | if(1. == fac) { |
---|
542 | safetyHelper->ReLocateWithinVolume(newPosition); |
---|
543 | |
---|
544 | } else { |
---|
545 | // check safety after displacement |
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546 | G4double postsafety = safetyHelper->ComputeSafety(newPosition); |
---|
547 | |
---|
548 | // displacement to boundary |
---|
549 | if(postsafety <= 0.0) { |
---|
550 | safetyHelper->Locate(newPosition, newDirection); |
---|
551 | |
---|
552 | // not on the boundary |
---|
553 | } else { |
---|
554 | safetyHelper->ReLocateWithinVolume(newPosition); |
---|
555 | } |
---|
556 | } |
---|
557 | fParticleChange->ProposePosition(newPosition); |
---|
558 | } |
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559 | } |
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560 | } |
---|
561 | |
---|
562 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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563 | |
---|
564 | void G4MuMscModel::SampleSecondaries(std::vector<G4DynamicParticle*>*, |
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565 | const G4MaterialCutsCouple*, |
---|
566 | const G4DynamicParticle*, |
---|
567 | G4double, |
---|
568 | G4double) |
---|
569 | {} |
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570 | |
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571 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... |
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