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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 56 57 #include "G4IonCoulombCrossSection.hh" 57 #include "G4IonCoulombCrossSection.hh" 58 #include "G4PhysicalConstants.hh" 58 #include "G4PhysicalConstants.hh" 59 #include "Randomize.hh" 59 #include "Randomize.hh" 60 #include "G4Proton.hh" 60 #include "G4Proton.hh" 61 #include "G4Exp.hh" 61 #include "G4Exp.hh" 62 #include "G4Log.hh" 62 #include "G4Log.hh" 63 63 64 //....oooOO0OOooo........oooOO0OOooo........oo 64 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... 65 65 66 using namespace std; 66 using namespace std; 67 67 68 const G4double a0 = CLHEP::electron_mass_c2/0. 68 const G4double a0 = CLHEP::electron_mass_c2/0.88534; 69 69 70 G4IonCoulombCrossSection::G4IonCoulombCrossSec 70 G4IonCoulombCrossSection::G4IonCoulombCrossSection(): 71 cosThetaMin(1.0), 71 cosThetaMin(1.0), 72 cosThetaMax(-1.0), 72 cosThetaMax(-1.0), 73 alpha2(fine_structure_const*fine_structure_ 73 alpha2(fine_structure_const*fine_structure_const) 74 { 74 { 75 fNistManager = G4NistManager::Instance(); 75 fNistManager = G4NistManager::Instance(); 76 fG4pow = G4Pow::GetInstance(); 76 fG4pow = G4Pow::GetInstance(); 77 theProton = G4Proton::Proton(); 77 theProton = G4Proton::Proton(); 78 particle = nullptr; << 78 particle=0; 79 79 80 G4double p0 = electron_mass_c2*classic_elect 80 G4double p0 = electron_mass_c2*classic_electr_radius; 81 coeff = twopi*p0*p0; 81 coeff = twopi*p0*p0; 82 82 83 cosTetMinNuc=0; 83 cosTetMinNuc=0; 84 cosTetMaxNuc=0; 84 cosTetMaxNuc=0; 85 nucXSection =0; 85 nucXSection =0; 86 86 87 chargeSquare = spin = mass = 0.0; 87 chargeSquare = spin = mass = 0.0; 88 tkinLab = momLab2 = invbetaLab2 = tkin = mom 88 tkinLab = momLab2 = invbetaLab2 = tkin = mom2 = invbeta2 = 0.0; 89 89 90 targetZ = targetMass = screenZ = ScreenRSqua 90 targetZ = targetMass = screenZ = ScreenRSquare = etag = 0.0; 91 } 91 } >> 92 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... >> 93 >> 94 G4IonCoulombCrossSection::~G4IonCoulombCrossSection() >> 95 {} 92 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); 102 SetupParticle(p); 99 nucXSection = tkin = targetZ = mom2 = 0.0; 103 nucXSection = tkin = targetZ = mom2 = 0.0; 100 etag = DBL_MAX; 104 etag = DBL_MAX; 101 particle = p; 105 particle = p; 102 cosThetaMin = CosThetaLim; 106 cosThetaMin = CosThetaLim; 103 } 107 } 104 108 105 //....oooOO0OOooo........oooOO0OOooo........oo 109 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 106 110 107 void G4IonCoulombCrossSection::SetupKinematic( 111 void G4IonCoulombCrossSection::SetupKinematic(G4double ekin, G4double tmass) 108 { 112 { 109 if(ekin != tkinLab || tmass != targetMass) { 113 if(ekin != tkinLab || tmass != targetMass) { 110 114 111 // lab 115 // lab 112 tkinLab = ekin; 116 tkinLab = ekin; 113 momLab2 = tkinLab*(tkinLab + 2.0*mass); 117 momLab2 = tkinLab*(tkinLab + 2.0*mass); 114 invbetaLab2 = 1.0 + mass*mass/momLab2; 118 invbetaLab2 = 1.0 + mass*mass/momLab2; 115 119 116 G4double etot = tkinLab + mass; 120 G4double etot = tkinLab + mass; 117 G4double ptot = sqrt(momLab2); 121 G4double ptot = sqrt(momLab2); 118 G4double m12 = mass*mass; 122 G4double m12 = mass*mass; 119 // relativistic reduced mass from publucat 123 // relativistic reduced mass from publucation 120 // A.P. Martynenko, R.N. Faustov, Teoret. 124 // A.P. Martynenko, R.N. Faustov, Teoret. mat. Fiz. 64 (1985) 179 121 125 122 //incident particle & target nucleus 126 //incident particle & target nucleus 123 targetMass = tmass; 127 targetMass = tmass; 124 G4double Ecm=sqrt(m12 + targetMass*targetM 128 G4double Ecm=sqrt(m12 + targetMass*targetMass + 2.0*etot*targetMass); 125 G4double mu_rel=mass*targetMass/Ecm; 129 G4double mu_rel=mass*targetMass/Ecm; 126 G4double momCM= ptot*targetMass/Ecm; 130 G4double momCM= ptot*targetMass/Ecm; 127 // relative system 131 // relative system 128 mom2 = momCM*momCM; 132 mom2 = momCM*momCM; 129 invbeta2 = 1.0 + mu_rel*mu_rel/mom2; 133 invbeta2 = 1.0 + mu_rel*mu_rel/mom2; 130 tkin = momCM*sqrt(invbeta2) - mu_rel;//Eki 134 tkin = momCM*sqrt(invbeta2) - mu_rel;//Ekin of mu_rel 131 135 132 cosTetMinNuc = cosThetaMin; 136 cosTetMinNuc = cosThetaMin; 133 cosTetMaxNuc = cosThetaMax; 137 cosTetMaxNuc = cosThetaMax; 134 } 138 } 135 } 139 } 136 140 137 //....oooOO0OOooo........oooOO0OOooo........oo 141 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 138 142 139 void G4IonCoulombCrossSection::SetupTarget(G4d 143 void G4IonCoulombCrossSection::SetupTarget(G4double Z, G4double e, 140 G4int) 144 G4int) 141 { 145 { 142 if(Z != targetZ || e != etag) { 146 if(Z != targetZ || e != etag) { 143 etag = e; 147 etag = e; 144 targetZ = Z; 148 targetZ = Z; 145 G4int iz= G4lrint(Z); 149 G4int iz= G4lrint(Z); 146 150 147 SetScreenRSquare(iz); 151 SetScreenRSquare(iz); 148 screenZ = 0; 152 screenZ = 0; 149 screenZ = ScreenRSquare/mom2; 153 screenZ = ScreenRSquare/mom2; 150 //heavycorr = 0; 154 //heavycorr = 0; 151 // G4cout<< "heavycorr "<<heavycorr<<G4en 155 // G4cout<< "heavycorr "<<heavycorr<<G4endl; 152 156 153 G4double corr=5.*twopi*Z*std::sqrt(chargeS 157 G4double corr=5.*twopi*Z*std::sqrt(chargeSquare*alpha2); 154 corr=G4Exp(G4Log(corr)*0.04); 158 corr=G4Exp(G4Log(corr)*0.04); 155 screenZ *=0.5*(1.13 + corr*3.76*Z*Z*charge 159 screenZ *=0.5*(1.13 + corr*3.76*Z*Z*chargeSquare*invbeta2*alpha2); 156 // G4cout<<" heavycorr Z e corr....2As "<< 160 // G4cout<<" heavycorr Z e corr....2As "<< heavycorr << "\t" 157 // <<Z <<"\t"<<e/MeV <<"\t"<<screenZ<<G4e 161 // <<Z <<"\t"<<e/MeV <<"\t"<<screenZ<<G4endl; 158 162 159 if(1 == iz && particle == theProton && cos 163 if(1 == iz && particle == theProton && cosTetMaxNuc < 0.0) { 160 cosTetMaxNuc = 0.0; 164 cosTetMaxNuc = 0.0; 161 } 165 } 162 } 166 } 163 } 167 } 164 168 165 //....oooOO0OOooo........oooOO0OOooo........oo 169 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 166 170 167 void G4IonCoulombCrossSection::SetScreenRSquar 171 void G4IonCoulombCrossSection::SetScreenRSquare(G4int iz) 168 { 172 { 169 //for proton Thomas-Fermi screening length 173 //for proton Thomas-Fermi screening length 170 G4int Z1 = G4lrint(std::sqrt(chargeSquare)); 174 G4int Z1 = G4lrint(std::sqrt(chargeSquare)); 171 G4double Z113 = fG4pow->Z13(iz); 175 G4double Z113 = fG4pow->Z13(iz); 172 G4double Z1023 = fG4pow->powZ(Z1,0.23); 176 G4double Z1023 = fG4pow->powZ(Z1,0.23); 173 G4double Z2023 = fG4pow->powZ(iz,0.23); 177 G4double Z2023 = fG4pow->powZ(iz,0.23); 174 G4double x=a0*(Z1023+Z2023); 178 G4double x=a0*(Z1023+Z2023); 175 179 176 // Universal screening length 180 // Universal screening length 177 if(particle == theProton){ 181 if(particle == theProton){ 178 x = a0*Z113; 182 x = a0*Z113; 179 } 183 } 180 184 181 ScreenRSquare = alpha2*x*x; 185 ScreenRSquare = alpha2*x*x; 182 } 186 } 183 187 184 //....oooOO0OOooo........oooOO0OOooo........oo 188 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 185 189 186 G4double G4IonCoulombCrossSection::NuclearCros 190 G4double G4IonCoulombCrossSection::NuclearCrossSection() 187 { 191 { 188 // This method needs initialisation before b 192 // This method needs initialisation before be called 189 // scattering with target nucleus 193 // scattering with target nucleus 190 G4double fac = coeff*targetZ*(targetZ)*charg 194 G4double fac = coeff*targetZ*(targetZ)*chargeSquare*invbeta2/mom2; 191 195 192 nucXSection = 0.0; 196 nucXSection = 0.0; 193 197 194 G4double x = 1.0 - cosTetMinNuc; 198 G4double x = 1.0 - cosTetMinNuc; 195 G4double x1 = x + screenZ; 199 G4double x1 = x + screenZ; 196 200 197 // scattering with nucleus 201 // scattering with nucleus 198 if(cosTetMaxNuc < cosTetMinNuc) { 202 if(cosTetMaxNuc < cosTetMinNuc) { 199 nucXSection = fac*(cosTetMinNuc - cosTetMa 203 nucXSection = fac*(cosTetMinNuc - cosTetMaxNuc)/ 200 (x1*(1.0 - cosTetMaxNuc + screenZ)); 204 (x1*(1.0 - cosTetMaxNuc + screenZ)); 201 } 205 } 202 206 203 return nucXSection; 207 return nucXSection; 204 } 208 } 205 209 206 //....oooOO0OOooo........oooOO0OOooo........oo 210 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... 207 211 208 G4double G4IonCoulombCrossSection::SampleCosin 212 G4double G4IonCoulombCrossSection::SampleCosineTheta() 209 { 213 { 210 G4double z1 = 0.0; 214 G4double z1 = 0.0; 211 if(cosTetMaxNuc < cosTetMinNuc) { 215 if(cosTetMaxNuc < cosTetMinNuc) { 212 216 213 G4double x1 = 1. - cosTetMinNuc + screenZ; 217 G4double x1 = 1. - cosTetMinNuc + screenZ; 214 G4double x2 = 1. - cosTetMaxNuc + screenZ; 218 G4double x2 = 1. - cosTetMaxNuc + screenZ; 215 G4double dx = cosTetMinNuc - cosTetMaxNuc; 219 G4double dx = cosTetMinNuc - cosTetMaxNuc; 216 z1 = x1*x2/(x1 + G4UniformRand()*dx) - scr 220 z1 = x1*x2/(x1 + G4UniformRand()*dx) - screenZ; 217 } 221 } 218 return z1; 222 return z1; 219 } 223 } 220 224 221 //....oooOO0OOooo........oooOO0OOooo........oo 225 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...... 222 226 223 227 224 228 225 229 226 230