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Vladymyrov) 41 // 13.11.2007 Use low-energy asymptotic from [ 41 // 13.11.2007 Use low-energy asymptotic from [3] (V.Ivanchenko) 42 // 42 // 43 // 43 // 44 // ------------------------------------------- 44 // ------------------------------------------------------------------- 45 // References 45 // References 46 // [1] Steven P. Ahlen: Energy loss of relativ 46 // [1] Steven P. Ahlen: Energy loss of relativistic heavy ionizing particles, 47 // S.P. Ahlen, Rev. Mod. Phys 52(1980), p1 47 // S.P. Ahlen, Rev. Mod. Phys 52(1980), p121 48 // [2] K.A. Milton arXiv:hep-ex/0602040 48 // [2] K.A. Milton arXiv:hep-ex/0602040 49 // [3] S.P. Ahlen and K. Kinoshita, Phys. Rev. 49 // [3] S.P. Ahlen and K. Kinoshita, Phys. Rev. D26 (1982) 2347 50 50 51 51 52 //....oooOO0OOooo........oooOO0OOooo........oo 52 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 53 //....oooOO0OOooo........oooOO0OOooo........oo 53 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 54 54 55 #include "G4mplIonisationModel.hh" 55 #include "G4mplIonisationModel.hh" 56 #include "Randomize.hh" 56 #include "Randomize.hh" 57 #include "G4PhysicalConstants.hh" 57 #include "G4PhysicalConstants.hh" 58 #include "G4SystemOfUnits.hh" 58 #include "G4SystemOfUnits.hh" 59 #include "G4ParticleChangeForLoss.hh" 59 #include "G4ParticleChangeForLoss.hh" 60 #include "G4ProductionCutsTable.hh" 60 #include "G4ProductionCutsTable.hh" 61 #include "G4MaterialCutsCouple.hh" 61 #include "G4MaterialCutsCouple.hh" 62 #include "G4Log.hh" 62 #include "G4Log.hh" 63 #include "G4Pow.hh" << 64 63 65 //....oooOO0OOooo........oooOO0OOooo........oo 64 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 66 65 >> 66 using namespace std; >> 67 67 std::vector<G4double>* G4mplIonisationModel::d 68 std::vector<G4double>* G4mplIonisationModel::dedx0 = nullptr; 68 69 69 G4mplIonisationModel::G4mplIonisationModel(G4d 70 G4mplIonisationModel::G4mplIonisationModel(G4double mCharge, const G4String& nam) 70 : G4VEmModel(nam),G4VEmFluctuationModel(nam) 71 : G4VEmModel(nam),G4VEmFluctuationModel(nam), 71 magCharge(mCharge), 72 magCharge(mCharge), 72 twoln10(G4Log(100.0)), << 73 twoln10(log(100.0)), 73 betalow(0.01), 74 betalow(0.01), 74 betalim(0.1), 75 betalim(0.1), 75 beta2lim(betalim*betalim), 76 beta2lim(betalim*betalim), 76 bg2lim(beta2lim*(1.0 + beta2lim)) 77 bg2lim(beta2lim*(1.0 + beta2lim)) 77 { 78 { 78 nmpl = G4int(std::abs(magCharge) * 2 * CLHEP << 79 nmpl = G4int(abs(magCharge) * 2 * fine_structure_const + 0.5); 79 if(nmpl > 6) { nmpl = 6; } 80 if(nmpl > 6) { nmpl = 6; } 80 else if(nmpl < 1) { nmpl = 1; } 81 else if(nmpl < 1) { nmpl = 1; } 81 pi_hbarc2_over_mc2 = CLHEP::pi*CLHEP::hbarc* << 82 pi_hbarc2_over_mc2 = pi * hbarc * hbarc / electron_mass_c2; 82 chargeSquare = magCharge * magCharge; 83 chargeSquare = magCharge * magCharge; 83 dedxlim = 45.*nmpl*nmpl*CLHEP::GeV*CLHEP::cm << 84 dedxlim = 45.*nmpl*nmpl*GeV*cm2/g; >> 85 fParticleChange = nullptr; >> 86 monopole = nullptr; >> 87 mass = 0.0; 84 } 88 } 85 89 86 //....oooOO0OOooo........oooOO0OOooo........oo 90 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 87 91 88 G4mplIonisationModel::~G4mplIonisationModel() 92 G4mplIonisationModel::~G4mplIonisationModel() 89 { 93 { 90 if(IsMaster()) { delete dedx0; } 94 if(IsMaster()) { delete dedx0; } 91 } 95 } 92 96 93 //....oooOO0OOooo........oooOO0OOooo........oo 97 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 94 98 95 void G4mplIonisationModel::SetParticle(const G 99 void G4mplIonisationModel::SetParticle(const G4ParticleDefinition* p) 96 { 100 { 97 monopole = p; 101 monopole = p; 98 mass = monopole->GetPDGMass(); 102 mass = monopole->GetPDGMass(); 99 G4double emin = 103 G4double emin = 100 std::min(LowEnergyLimit(),0.1*mass*(1./std << 104 std::min(LowEnergyLimit(),0.1*mass*(1./sqrt(1. - betalow*betalow) - 1.)); 101 G4double emax = 105 G4double emax = 102 std::max(HighEnergyLimit(),10.*mass*(1./st << 106 std::max(HighEnergyLimit(),10.*mass*(1./sqrt(1. - beta2lim) - 1.)); 103 SetLowEnergyLimit(emin); 107 SetLowEnergyLimit(emin); 104 SetHighEnergyLimit(emax); 108 SetHighEnergyLimit(emax); 105 } 109 } 106 110 107 //....oooOO0OOooo........oooOO0OOooo........oo 111 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 108 112 109 void G4mplIonisationModel::Initialise(const G4 113 void G4mplIonisationModel::Initialise(const G4ParticleDefinition* p, 110 const G4DataVector&) 114 const G4DataVector&) 111 { 115 { 112 if(nullptr == monopole) { SetParticle(p); } << 116 if(!monopole) { SetParticle(p); } 113 if(nullptr == fParticleChange) { fParticleCh << 117 if(!fParticleChange) { fParticleChange = GetParticleChangeForLoss(); } 114 if(IsMaster()) { 118 if(IsMaster()) { 115 if(nullptr == dedx0) { dedx0 = new std::ve << 119 if(!dedx0) { dedx0 = new std::vector<G4double>; } 116 G4ProductionCutsTable* theCoupleTable= 120 G4ProductionCutsTable* theCoupleTable= 117 G4ProductionCutsTable::GetProductionCuts 121 G4ProductionCutsTable::GetProductionCutsTable(); 118 G4int numOfCouples = (G4int)theCoupleTable << 122 G4int numOfCouples = theCoupleTable->GetTableSize(); 119 G4int n = (G4int)dedx0->size(); << 123 G4int n = dedx0->size(); 120 if(n < numOfCouples) { dedx0->resize(numOf 124 if(n < numOfCouples) { dedx0->resize(numOfCouples); } 121 125 122 G4Pow* g4calc = G4Pow::GetInstance(); << 126 // initialise vector 123 << 124 // initialise vector assuming low conducti << 125 for(G4int i=0; i<numOfCouples; ++i) { 127 for(G4int i=0; i<numOfCouples; ++i) { 126 128 127 const G4Material* material = 129 const G4Material* material = 128 theCoupleTable->GetMaterialCutsCouple( << 130 theCoupleTable->GetMaterialCutsCouple(i)->GetMaterial(); 129 G4double eDensity = material->GetElectro 131 G4double eDensity = material->GetElectronDensity(); 130 G4double vF2 = 2*electron_Compton_length << 132 G4double vF = electron_Compton_length*pow(3.*pi*pi*eDensity,0.3333333333); 131 (*dedx0)[i] = pi_hbarc2_over_mc2*eDensit 133 (*dedx0)[i] = pi_hbarc2_over_mc2*eDensity*nmpl*nmpl* 132 (G4Log(vF2/fine_structure_const) - 0.5 << 134 (G4Log(2.*vF/fine_structure_const) - 0.5)/vF; 133 } 135 } 134 } 136 } 135 } 137 } 136 138 137 //....oooOO0OOooo........oooOO0OOooo........oo 139 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 138 140 139 G4double G4mplIonisationModel::ComputeDEDXPerV 141 G4double G4mplIonisationModel::ComputeDEDXPerVolume(const G4Material* material, 140 const G4ParticleDefinition* p, 142 const G4ParticleDefinition* p, 141 G4double kineticEnergy, 143 G4double kineticEnergy, 142 G4double) 144 G4double) 143 { 145 { 144 if(nullptr == monopole) { SetParticle(p); } << 146 if(!monopole) { SetParticle(p); } 145 G4double tau = kineticEnergy / mass; 147 G4double tau = kineticEnergy / mass; 146 G4double gam = tau + 1.0; 148 G4double gam = tau + 1.0; 147 G4double bg2 = tau * (tau + 2.0); 149 G4double bg2 = tau * (tau + 2.0); 148 G4double beta2 = bg2 / (gam * gam); 150 G4double beta2 = bg2 / (gam * gam); 149 G4double beta = std::sqrt(beta2); << 151 G4double beta = sqrt(beta2); 150 152 151 // low-energy asymptotic formula 153 // low-energy asymptotic formula 152 //G4double dedx = dedxlim*beta*material->Ge 154 //G4double dedx = dedxlim*beta*material->GetDensity(); 153 G4double dedx = (*dedx0)[CurrentCouple()->Ge 155 G4double dedx = (*dedx0)[CurrentCouple()->GetIndex()]*beta; 154 156 155 // above asymptotic 157 // above asymptotic 156 if(beta > betalow) { 158 if(beta > betalow) { 157 159 158 // high energy 160 // high energy 159 if(beta >= betalim) { 161 if(beta >= betalim) { 160 dedx = ComputeDEDXAhlen(material, bg2); 162 dedx = ComputeDEDXAhlen(material, bg2); 161 163 162 } else { 164 } else { 163 165 164 //G4double dedx1 = dedxlim*betalow*mater 166 //G4double dedx1 = dedxlim*betalow*material->GetDensity(); 165 G4double dedx1 = (*dedx0)[CurrentCouple( 167 G4double dedx1 = (*dedx0)[CurrentCouple()->GetIndex()]*betalow; 166 G4double dedx2 = ComputeDEDXAhlen(materi 168 G4double dedx2 = ComputeDEDXAhlen(material, bg2lim); 167 169 168 // extrapolation between two formula 170 // extrapolation between two formula 169 G4double kapa2 = beta - betalow; 171 G4double kapa2 = beta - betalow; 170 G4double kapa1 = betalim - beta; 172 G4double kapa1 = betalim - beta; 171 dedx = (kapa1*dedx1 + kapa2*dedx2)/(kapa 173 dedx = (kapa1*dedx1 + kapa2*dedx2)/(kapa1 + kapa2); 172 } 174 } 173 } 175 } 174 return dedx; 176 return dedx; 175 } 177 } 176 178 177 //....oooOO0OOooo........oooOO0OOooo........oo 179 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 178 180 179 G4double G4mplIonisationModel::ComputeDEDXAhle 181 G4double G4mplIonisationModel::ComputeDEDXAhlen(const G4Material* material, 180 G4double bg2) 182 G4double bg2) 181 { 183 { 182 G4double eDensity = material->GetElectronDen 184 G4double eDensity = material->GetElectronDensity(); 183 G4double eexc = material->GetIonisation()-> 185 G4double eexc = material->GetIonisation()->GetMeanExcitationEnergy(); 184 G4double cden = material->GetIonisation()-> 186 G4double cden = material->GetIonisation()->GetCdensity(); 185 G4double mden = material->GetIonisation()-> 187 G4double mden = material->GetIonisation()->GetMdensity(); 186 G4double aden = material->GetIonisation()-> 188 G4double aden = material->GetIonisation()->GetAdensity(); 187 G4double x0den = material->GetIonisation()-> 189 G4double x0den = material->GetIonisation()->GetX0density(); 188 G4double x1den = material->GetIonisation()-> 190 G4double x1den = material->GetIonisation()->GetX1density(); 189 191 190 // Ahlen's formula for nonconductors, [1]p15 192 // Ahlen's formula for nonconductors, [1]p157, f(5.7) 191 G4double dedx = std::log(2.0 * electron_mass << 193 G4double dedx = log(2.0 * electron_mass_c2 * bg2 / eexc) - 0.5; 192 194 193 // Kazama et al. cross-section correction 195 // Kazama et al. cross-section correction 194 G4double k = 0.406; 196 G4double k = 0.406; 195 if(nmpl > 1) k = 0.346; 197 if(nmpl > 1) k = 0.346; 196 198 197 // Bloch correction 199 // Bloch correction 198 const G4double B[7] = { 0.0, 0.248, 0.672, 1 200 const G4double B[7] = { 0.0, 0.248, 0.672, 1.022, 1.243, 1.464, 1.685}; 199 201 200 dedx += 0.5 * k - B[nmpl]; 202 dedx += 0.5 * k - B[nmpl]; 201 203 202 // density effect correction 204 // density effect correction 203 G4double deltam; 205 G4double deltam; 204 G4double x = std::log(bg2) / twoln10; << 206 G4double x = log(bg2) / twoln10; 205 if ( x >= x0den ) { 207 if ( x >= x0den ) { 206 deltam = twoln10 * x - cden; 208 deltam = twoln10 * x - cden; 207 if ( x < x1den ) deltam += aden * std::pow << 209 if ( x < x1den ) deltam += aden * pow((x1den-x), mden); 208 dedx -= 0.5 * deltam; 210 dedx -= 0.5 * deltam; 209 } 211 } 210 212 211 // now compute the total ionization loss 213 // now compute the total ionization loss 212 dedx *= pi_hbarc2_over_mc2 * eDensity * nmp 214 dedx *= pi_hbarc2_over_mc2 * eDensity * nmpl * nmpl; 213 215 214 if (dedx < 0.0) dedx = 0.; 216 if (dedx < 0.0) dedx = 0.; 215 return dedx; 217 return dedx; 216 } 218 } 217 219 218 //....oooOO0OOooo........oooOO0OOooo........oo 220 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 219 221 220 void G4mplIonisationModel::SampleSecondaries(s 222 void G4mplIonisationModel::SampleSecondaries(std::vector<G4DynamicParticle*>*, 221 const G4MaterialCutsCouple*, 223 const G4MaterialCutsCouple*, 222 const G4DynamicParticle*, 224 const G4DynamicParticle*, 223 G4double, 225 G4double, 224 G4double) 226 G4double) 225 {} 227 {} 226 228 227 //....oooOO0OOooo........oooOO0OOooo........oo 229 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 228 230 229 G4double G4mplIonisationModel::SampleFluctuati 231 G4double G4mplIonisationModel::SampleFluctuations( 230 const G4MaterialCutsCouple* cou 232 const G4MaterialCutsCouple* couple, 231 const G4DynamicParticle* dp, 233 const G4DynamicParticle* dp, 232 const G << 234 G4double tmax, 233 const G << 235 G4double length, 234 const G4double length, << 236 G4double meanLoss) 235 const G4double meanLoss) << 236 { 237 { 237 G4double siga = Dispersion(couple->GetMateri << 238 G4double siga = Dispersion(couple->GetMaterial(),dp,tmax,length); 238 G4double loss = meanLoss; 239 G4double loss = meanLoss; 239 siga = std::sqrt(siga); << 240 siga = sqrt(siga); 240 G4double twomeanLoss = meanLoss + meanLoss; 241 G4double twomeanLoss = meanLoss + meanLoss; 241 242 242 if(twomeanLoss < siga) { 243 if(twomeanLoss < siga) { 243 G4double x; 244 G4double x; 244 do { 245 do { 245 loss = twomeanLoss*G4UniformRand(); 246 loss = twomeanLoss*G4UniformRand(); 246 x = (loss - meanLoss)/siga; 247 x = (loss - meanLoss)/siga; 247 // Loop checking, 07-Aug-2015, Vladimir 248 // Loop checking, 07-Aug-2015, Vladimir Ivanchenko 248 } while (1.0 - 0.5*x*x < G4UniformRand()); 249 } while (1.0 - 0.5*x*x < G4UniformRand()); 249 } else { 250 } else { 250 do { 251 do { 251 loss = G4RandGauss::shoot(meanLoss,siga) 252 loss = G4RandGauss::shoot(meanLoss,siga); 252 // Loop checking, 07-Aug-2015, Vladimir 253 // Loop checking, 07-Aug-2015, Vladimir Ivanchenko 253 } while (0.0 > loss || loss > twomeanLoss) 254 } while (0.0 > loss || loss > twomeanLoss); 254 } 255 } 255 return loss; 256 return loss; 256 } 257 } 257 258 258 //....oooOO0OOooo........oooOO0OOooo........oo 259 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 259 260 260 G4double G4mplIonisationModel::Dispersion(cons 261 G4double G4mplIonisationModel::Dispersion(const G4Material* material, 261 const G4DynamicParticle* dp, 262 const G4DynamicParticle* dp, 262 const G4double tcut, << 263 G4double tmax, 263 const G4double tmax, << 264 G4double length) 264 const G4double length) << 265 { 265 { 266 G4double siga = 0.0; 266 G4double siga = 0.0; 267 G4double tau = dp->GetKineticEnergy()/mass 267 G4double tau = dp->GetKineticEnergy()/mass; 268 if(tau > 0.0) { 268 if(tau > 0.0) { 269 const G4double beta = dp->GetBeta(); << 269 G4double electronDensity = material->GetElectronDensity(); 270 siga = (tmax/(beta*beta) - 0.5*tcut) * tw << 270 G4double gam = tau + 1.0; 271 * material->GetElectronDensity() * charg << 271 G4double invbeta2 = (gam*gam)/(tau * (tau+2.0)); >> 272 siga = (invbeta2 - 0.5) * twopi_mc2_rcl2 * tmax * length >> 273 * electronDensity * chargeSquare; 272 } 274 } 273 return siga; 275 return siga; 274 } 276 } 275 277 276 //....oooOO0OOooo........oooOO0OOooo........oo 278 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 277 279