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Boschini et al. "Nuclear and Non- 43 // M.J. Boschini et al. "Nuclear and Non-Ionizing Energy-Loss 44 // for Coulomb Scattered Particles from L 44 // for Coulomb Scattered Particles from Low Energy up to Relativistic 45 // Regime in Space Radiation Environment" 45 // Regime in Space Radiation Environment" 46 // Accepted for publication in the Procee 46 // Accepted for publication in the Proceedings of the ICATPP Conference 47 // on Cosmic Rays for Particle and Astrop 47 // on Cosmic Rays for Particle and Astroparticle Physics, Villa Olmo, 7-8 48 // October, 2010, to be published by Wor 48 // October, 2010, to be published by World Scientific (Singapore). 49 // 49 // 50 // Available for downloading at: 50 // Available for downloading at: 51 // http://arxiv.org/abs/1011.4822 51 // http://arxiv.org/abs/1011.4822 52 // 52 // 53 // ------------------------------------------- 53 // ------------------------------------------------------------------- 54 // 54 // 55 //....oooOO0OOooo........oooOO0OOooo........oo 55 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 56 << 57 #include "G4IonCoulombCrossSection.hh" 56 #include "G4IonCoulombCrossSection.hh" 58 #include "G4PhysicalConstants.hh" << 59 #include "Randomize.hh" 57 #include "Randomize.hh" 60 #include "G4Proton.hh" 58 #include "G4Proton.hh" 61 #include "G4Exp.hh" << 59 #include "G4LossTableManager.hh" 62 #include "G4Log.hh" << 63 60 64 //....oooOO0OOooo........oooOO0OOooo........oo 61 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... 65 62 66 using namespace std; << 67 63 68 const G4double a0 = CLHEP::electron_mass_c2/0. << 64 using namespace std; 69 65 70 G4IonCoulombCrossSection::G4IonCoulombCrossSec 66 G4IonCoulombCrossSection::G4IonCoulombCrossSection(): 71 cosThetaMin(1.0), 67 cosThetaMin(1.0), 72 cosThetaMax(-1.0), 68 cosThetaMax(-1.0), 73 alpha2(fine_structure_const*fine_structure_ 69 alpha2(fine_structure_const*fine_structure_const) 74 { 70 { 75 fNistManager = G4NistManager::Instance(); << 71 fNistManager = G4NistManager::Instance(); 76 fG4pow = G4Pow::GetInstance(); << 72 theProton = G4Proton::Proton(); 77 theProton = G4Proton::Proton(); << 73 particle=0; 78 particle = nullptr; << 74 79 << 75 G4double p0 = electron_mass_c2*classic_electr_radius; 80 G4double p0 = electron_mass_c2*classic_elect << 76 coeff = twopi*p0*p0; 81 coeff = twopi*p0*p0; << 77 82 << 78 cosTetMinNuc=0; 83 cosTetMinNuc=0; << 79 cosTetMaxNuc=0; 84 cosTetMaxNuc=0; << 80 nucXSection =0; 85 nucXSection =0; << 81 86 82 87 chargeSquare = spin = mass = 0.0; << 83 chargeSquare = spin = mass =0; 88 tkinLab = momLab2 = invbetaLab2 = tkin = mom << 84 tkinLab = momLab2 = invbetaLab2=0; >> 85 tkin = mom2 = invbeta2=0; >> 86 >> 87 targetZ = targetMass = screenZ =0; >> 88 ScreenRSquare=0.; >> 89 >> 90 etag = ecut = 0.0; 89 91 90 targetZ = targetMass = screenZ = ScreenRSqua << 91 } 92 } >> 93 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 92 94 >> 95 G4IonCoulombCrossSection::~G4IonCoulombCrossSection() >> 96 {} 93 //....oooOO0OOooo........oooOO0OOooo........oo 97 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 94 98 95 void G4IonCoulombCrossSection::Initialise(cons 99 void G4IonCoulombCrossSection::Initialise(const G4ParticleDefinition* p, 96 G4do 100 G4double CosThetaLim) 97 { 101 { 98 SetupParticle(p); << 99 nucXSection = tkin = targetZ = mom2 = 0.0; << 100 etag = DBL_MAX; << 101 particle = p; << 102 cosThetaMin = CosThetaLim; << 103 } << 104 102 >> 103 SetupParticle(p); >> 104 nucXSection = 0.0; >> 105 tkin = targetZ = mom2 = DBL_MIN; >> 106 ecut = etag = DBL_MAX; >> 107 particle = p; >> 108 >> 109 >> 110 cosThetaMin = CosThetaLim; >> 111 >> 112 } 105 //....oooOO0OOooo........oooOO0OOooo........oo 113 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 106 114 107 void G4IonCoulombCrossSection::SetupKinematic( << 115 void G4IonCoulombCrossSection::SetupKinematic(G4double ekin, >> 116 G4double cut,G4int iz ) 108 { 117 { 109 if(ekin != tkinLab || tmass != targetMass) { << 118 if(ekin != tkinLab || ecut != cut) { >> 119 >> 120 // lab >> 121 tkinLab = ekin; >> 122 momLab2 = tkinLab*(tkinLab + 2.0*mass); >> 123 invbetaLab2 = 1.0 + mass*mass/momLab2; 110 124 111 // lab << 125 G4double etot = tkinLab + mass; 112 tkinLab = ekin; << 126 G4double ptot = sqrt(momLab2); 113 momLab2 = tkinLab*(tkinLab + 2.0*mass); << 127 G4double m12 = mass*mass; 114 invbetaLab2 = 1.0 + mass*mass/momLab2; << 115 128 116 G4double etot = tkinLab + mass; << 129 targetMass=fNistManager->GetAtomicMassAmu(iz)*amu_c2; 117 G4double ptot = sqrt(momLab2); << 130 G4double m2 = targetMass; 118 G4double m12 = mass*mass; << 131 119 // relativistic reduced mass from publucat << 132 // relativistic reduced mass from publucation 120 // A.P. Martynenko, R.N. Faustov, Teoret. << 133 // A.P. Martynenko, R.N. Faustov, Teoret. mat. Fiz. 64 (1985) 179 121 134 122 //incident particle & target nucleus << 135 //incident particle & target nucleus 123 targetMass = tmass; << 136 G4double Ecm=sqrt(m12 + m2*m2 + 2.0*etot*m2); 124 G4double Ecm=sqrt(m12 + targetMass*targetM << 137 G4double mu_rel=mass*m2/Ecm; 125 G4double mu_rel=mass*targetMass/Ecm; << 138 G4double momCM= ptot*m2/Ecm; 126 G4double momCM= ptot*targetMass/Ecm; << 139 // relative system 127 // relative system << 140 mom2 = momCM*momCM; 128 mom2 = momCM*momCM; << 141 invbeta2 = 1.0 + mu_rel*mu_rel/mom2; 129 invbeta2 = 1.0 + mu_rel*mu_rel/mom2; << 142 tkin = momCM*sqrt(invbeta2) - mu_rel;//Ekin of mu_rel 130 tkin = momCM*sqrt(invbeta2) - mu_rel;//Eki << 143 //......................................................... 131 << 132 cosTetMinNuc = cosThetaMin; << 133 cosTetMaxNuc = cosThetaMax; << 134 } << 135 } << 136 144 >> 145 cosTetMinNuc = cosThetaMin; >> 146 cosTetMaxNuc = cosThetaMax; >> 147 >> 148 } >> 149 >> 150 } 137 //....oooOO0OOooo........oooOO0OOooo........oo 151 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 138 152 139 void G4IonCoulombCrossSection::SetupTarget(G4d << 153 140 G4int) << 154 void G4IonCoulombCrossSection::SetupTarget(G4double Z, G4double e, G4int heavycorr) 141 { << 155 { 142 if(Z != targetZ || e != etag) { << 156 if(Z != targetZ || e != etag) { 143 etag = e; << 157 etag = e; 144 targetZ = Z; << 158 targetZ = Z; 145 G4int iz= G4lrint(Z); << 159 G4int iz= G4int(Z); 146 << 160 147 SetScreenRSquare(iz); << 161 SetScreenRSquare(iz); 148 screenZ = 0; << 162 screenZ =0; 149 screenZ = ScreenRSquare/mom2; << 163 screenZ = ScreenRSquare/mom2; 150 //heavycorr = 0; << 164 151 // G4cout<< "heavycorr "<<heavycorr<<G4en << 165 // G4cout<< "heavycorr "<<heavycorr<<G4endl; 152 << 166 153 G4double corr=5.*twopi*Z*std::sqrt(chargeS << 167 if(heavycorr!=0 && particle != theProton){ 154 corr=G4Exp(G4Log(corr)*0.04); << 168 G4double corr=5.*twopi*Z*std::sqrt(chargeSquare*alpha2); 155 screenZ *=0.5*(1.13 + corr*3.76*Z*Z*charge << 169 corr=std::pow(corr,0.12); 156 // G4cout<<" heavycorr Z e corr....2As "<< << 170 screenZ *=(1.13 + corr*3.76*Z*Z*chargeSquare*invbeta2*alpha2)/2.; 157 // <<Z <<"\t"<<e/MeV <<"\t"<<screenZ<<G4e << 171 // G4cout<<" heavycorr Z e corr....2As "<< heavycorr << "\t" 158 << 172 // <<Z <<"\t"<<e/MeV <<"\t"<<screenZ<<G4endl; 159 if(1 == iz && particle == theProton && cos << 173 160 cosTetMaxNuc = 0.0; << 174 }else{ screenZ *=(1.13 + 3.76*Z*Z*chargeSquare*invbeta2*alpha2)/2.; 161 } << 175 // G4cout<<" heavycorr Z e....2As "<< heavycorr << "\t" 162 } << 176 // <<Z <<"\t"<< e/MeV <<"\t" <<screenZ<<G4endl; >> 177 } >> 178 >> 179 if(1 == iz && particle == theProton && cosTetMaxNuc < 0.0) { >> 180 cosTetMaxNuc = 0.0; >> 181 } >> 182 >> 183 } 163 } 184 } 164 185 165 //....oooOO0OOooo........oooOO0OOooo........oo 186 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... >> 187 void G4IonCoulombCrossSection::SetScreenRSquare(G4int iz){ 166 188 167 void G4IonCoulombCrossSection::SetScreenRSquar << 189 G4double a0 = electron_mass_c2/0.88534; 168 { << 169 //for proton Thomas-Fermi screening length << 170 G4int Z1 = G4lrint(std::sqrt(chargeSquare)); << 171 G4double Z113 = fG4pow->Z13(iz); << 172 G4double Z1023 = fG4pow->powZ(Z1,0.23); << 173 G4double Z2023 = fG4pow->powZ(iz,0.23); << 174 G4double x=a0*(Z1023+Z2023); << 175 << 176 // Universal screening length << 177 if(particle == theProton){ << 178 x = a0*Z113; << 179 } << 180 190 181 ScreenRSquare = alpha2*x*x; << 191 //target nucleus 182 } << 192 G4double Z1=std::sqrt(chargeSquare); >> 193 G4double Z2=targetZ; >> 194 >> 195 G4double Z1023=std::pow(Z1,0.23); >> 196 G4double Z2023=std::pow(Z2,0.23); >> 197 >> 198 // Universal screening length >> 199 G4double x=a0*(Z1023+Z2023); >> 200 >> 201 //for proton Thomas-Fermi screening length >> 202 if(particle == theProton){ >> 203 x = a0*fNistManager->GetZ13(iz); >> 204 } >> 205 ScreenRSquare = alpha2*x*x; 183 206 >> 207 >> 208 } 184 //....oooOO0OOooo........oooOO0OOooo........oo 209 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 185 210 186 G4double G4IonCoulombCrossSection::NuclearCros 211 G4double G4IonCoulombCrossSection::NuclearCrossSection() 187 { 212 { 188 // This method needs initialisation before b << 213 // This method needs initialisation before be called 189 // scattering with target nucleus << 214 190 G4double fac = coeff*targetZ*(targetZ)*charg << 215 // scattering with target nucleus 191 << 216 G4double fac = coeff*targetZ*targetZ*chargeSquare*invbeta2/mom2; 192 nucXSection = 0.0; << 217 193 << 218 nucXSection = 0.0; 194 G4double x = 1.0 - cosTetMinNuc; << 219 195 G4double x1 = x + screenZ; << 220 G4double x = 1.0 - cosTetMinNuc; 196 << 221 G4double x1 = x + screenZ; 197 // scattering with nucleus << 222 198 if(cosTetMaxNuc < cosTetMinNuc) { << 223 // scattering with nucleus 199 nucXSection = fac*(cosTetMinNuc - cosTetMa << 224 if(cosTetMaxNuc < cosTetMinNuc) { 200 (x1*(1.0 - cosTetMaxNuc + screenZ)); << 225 201 } << 226 nucXSection =fac*(cosTetMinNuc - cosTetMaxNuc)/ >> 227 (x1*(1.0 - cosTetMaxNuc + screenZ)); >> 228 >> 229 } 202 230 203 return nucXSection; 231 return nucXSection; 204 } 232 } 205 233 206 //....oooOO0OOooo........oooOO0OOooo........oo 234 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 207 235 208 G4double G4IonCoulombCrossSection::SampleCosin 236 G4double G4IonCoulombCrossSection::SampleCosineTheta() 209 { << 237 { 210 G4double z1 = 0.0; << 238 211 if(cosTetMaxNuc < cosTetMinNuc) { << 239 if(cosTetMaxNuc >= cosTetMinNuc) return 0.0; 212 << 240 213 G4double x1 = 1. - cosTetMinNuc + screenZ; << 241 G4double x1 = 1. - cosTetMinNuc + screenZ; 214 G4double x2 = 1. - cosTetMaxNuc + screenZ; << 242 G4double x2 = 1. - cosTetMaxNuc + screenZ; 215 G4double dx = cosTetMinNuc - cosTetMaxNuc; << 243 G4double dx = cosTetMinNuc - cosTetMaxNuc; 216 z1 = x1*x2/(x1 + G4UniformRand()*dx) - scr << 244 G4double grej, z1; 217 } << 245 >> 246 z1 = x1*x2/(x1 + G4UniformRand()*dx) - screenZ; >> 247 grej = 1.0/(1.0 + z1); >> 248 >> 249 218 return z1; 250 return z1; 219 } 251 } 220 252 221 //....oooOO0OOooo........oooOO0OOooo........oo 253 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... 222 254 223 255 224 256 225 257 226 258