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Please see the license in the file LICENSE and URL above * 16 // * for the full disclaimer and the limitatio 16 // * for the full disclaimer and the limitation of liability. * 17 // * 17 // * * 18 // * This code implementation is the result 18 // * This code implementation is the result of the scientific and * 19 // * technical work of the GEANT4 collaboratio 19 // * technical work of the GEANT4 collaboration. * 20 // * 20 // * * 21 // * Parts of this code which have been devel 21 // * Parts of this code which have been developed by QinetiQ Ltd * 22 // * under contract to the European Space Agen 22 // * under contract to the European Space Agency (ESA) are the * 23 // * intellectual property of ESA. Rights to u 23 // * intellectual property of ESA. Rights to use, copy, modify and * 24 // * redistribute this software for general pu 24 // * redistribute this software for general public use are granted * 25 // * in compliance with any licensing, distrib 25 // * in compliance with any licensing, distribution and development * 26 // * policy adopted by the Geant4 Collaboratio 26 // * policy adopted by the Geant4 Collaboration. This code has been * 27 // * written by QinetiQ Ltd for the European S 27 // * written by QinetiQ Ltd for the European Space Agency, under ESA * 28 // * contract 17191/03/NL/LvH (Aurora Programm 28 // * contract 17191/03/NL/LvH (Aurora Programme). * 29 // * 29 // * * 30 // * By using, copying, modifying or distri 30 // * By using, copying, modifying or distributing the software (or * 31 // * any work based on the software) you ag 31 // * any work based on the software) you agree to acknowledge its * 32 // * use in resulting scientific publicati 32 // * use in resulting scientific publications, and indicate your * 33 // * acceptance of all terms of the Geant4 Sof 33 // * acceptance of all terms of the Geant4 Software license. * 34 // ******************************************* 34 // ******************************************************************** 35 // 35 // 36 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 36 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 37 // 37 // 38 // MODULE: G4EMDissociationCrossSection.cc 38 // MODULE: G4EMDissociationCrossSection.cc 39 // 39 // 40 // Version: B.1 40 // Version: B.1 41 // Date: 15/04/04 41 // Date: 15/04/04 42 // Author: P R Truscott 42 // Author: P R Truscott 43 // Organisation: QinetiQ Ltd, UK 43 // Organisation: QinetiQ Ltd, UK 44 // Customer: ESA/ESTEC, NOORDWIJK 44 // Customer: ESA/ESTEC, NOORDWIJK 45 // Contract: 17191/03/NL/LvH 45 // Contract: 17191/03/NL/LvH 46 // 46 // 47 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 47 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 48 // 48 // 49 // CHANGE HISTORY 49 // CHANGE HISTORY 50 // -------------- 50 // -------------- 51 // 51 // 52 // 17 October 2003, P R Truscott, QinetiQ Ltd, 52 // 17 October 2003, P R Truscott, QinetiQ Ltd, UK 53 // Created. 53 // Created. 54 // 54 // 55 // 15 March 2004, P R Truscott, QinetiQ Ltd, U 55 // 15 March 2004, P R Truscott, QinetiQ Ltd, UK 56 // Beta release 56 // Beta release 57 // 57 // 58 // 30 May 2005, J.P. Wellisch removed a compil 58 // 30 May 2005, J.P. Wellisch removed a compilation warning on gcc 3.4 for 59 // geant4 7.1. 59 // geant4 7.1. 60 // 09 November 2010, V.Ivanchenko make class a 60 // 09 November 2010, V.Ivanchenko make class applicable for Hydrogen but 61 // set cross section for Hyd 61 // set cross section for Hydrogen to zero 62 // 62 // 63 // 17 August 2011, V.Ivanchenko, provide migra 63 // 17 August 2011, V.Ivanchenko, provide migration to new design of cross 64 // sections considering this c 64 // sections considering this cross section as element-wise 65 // 65 // 66 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 66 // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 67 ////////////////////////////////////////////// 67 ////////////////////////////////////////////////////////////////////////////// 68 // 68 // 69 #include "G4EMDissociationCrossSection.hh" 69 #include "G4EMDissociationCrossSection.hh" 70 #include "G4PhysicalConstants.hh" 70 #include "G4PhysicalConstants.hh" 71 #include "G4SystemOfUnits.hh" 71 #include "G4SystemOfUnits.hh" 72 #include "G4ParticleTable.hh" 72 #include "G4ParticleTable.hh" 73 #include "G4IonTable.hh" 73 #include "G4IonTable.hh" 74 #include "G4HadTmpUtil.hh" 74 #include "G4HadTmpUtil.hh" 75 #include "globals.hh" 75 #include "globals.hh" 76 #include "G4NistManager.hh" 76 #include "G4NistManager.hh" 77 77 78 78 79 G4EMDissociationCrossSection::G4EMDissociation 79 G4EMDissociationCrossSection::G4EMDissociationCrossSection () 80 : G4VCrossSectionDataSet("Electromagnetic dis 80 : G4VCrossSectionDataSet("Electromagnetic dissociation") 81 { 81 { 82 // This function makes use of the class whic 82 // This function makes use of the class which can sample the virtual photon 83 // spectrum, G4EMDissociationSpectrum. 83 // spectrum, G4EMDissociationSpectrum. 84 84 85 thePhotonSpectrum = new G4EMDissociationSpec 85 thePhotonSpectrum = new G4EMDissociationSpectrum(); 86 86 87 // Define other constants. 87 // Define other constants. 88 88 89 r0 = 1.18 * fermi; 89 r0 = 1.18 * fermi; 90 J = 36.8 * MeV; 90 J = 36.8 * MeV; 91 Qprime = 17.0 * MeV; 91 Qprime = 17.0 * MeV; 92 epsilon = 0.0768; 92 epsilon = 0.0768; 93 xd = 0.25; 93 xd = 0.25; 94 } 94 } 95 95 96 ////////////////////////////////////////////// 96 ////////////////////////////////////////////////////////////////////////////// 97 97 98 G4EMDissociationCrossSection::~G4EMDissociatio 98 G4EMDissociationCrossSection::~G4EMDissociationCrossSection() 99 { 99 { 100 delete thePhotonSpectrum; 100 delete thePhotonSpectrum; 101 } 101 } 102 ////////////////////////////////////////////// 102 ///////////////////////////////////////////////////////////////////////////// 103 // 103 // 104 G4bool 104 G4bool 105 G4EMDissociationCrossSection::IsElementApplica 105 G4EMDissociationCrossSection::IsElementApplicable(const G4DynamicParticle* part, 106 G4int /*ZZ*/, const G4Material*) 106 G4int /*ZZ*/, const G4Material*) 107 { 107 { 108 // 108 // 109 // The condition for the applicability of this 109 // The condition for the applicability of this class is that the projectile 110 // must be an ion and the target must have mor 110 // must be an ion and the target must have more than one nucleon. In reality 111 // the value of A for either the projectile or 111 // the value of A for either the projectile or target could be much higher, 112 // since for cases where both he projectile an 112 // since for cases where both he projectile and target are medium to small 113 // Z, the probability of the EMD process is, I 113 // Z, the probability of the EMD process is, I think, VERY small. 114 // 114 // 115 if (G4ParticleTable::GetParticleTable()->Get 115 if (G4ParticleTable::GetParticleTable()->GetIonTable()->IsIon(part->GetDefinition())) { 116 return true; 116 return true; 117 } else { 117 } else { 118 return false; 118 return false; 119 } 119 } 120 } 120 } 121 121 122 ////////////////////////////////////////////// 122 ////////////////////////////////////////////////////////////////////////////// 123 // 123 // 124 G4double G4EMDissociationCrossSection::GetElem 124 G4double G4EMDissociationCrossSection::GetElementCrossSection 125 (const G4DynamicParticle* theDynamicParticle 125 (const G4DynamicParticle* theDynamicParticle, G4int Z, 126 const G4Material*) 126 const G4Material*) 127 { 127 { 128 // VI protection for Hydrogen 128 // VI protection for Hydrogen 129 if(1 >= Z) { return 0.0; } 129 if(1 >= Z) { return 0.0; } 130 << 130 131 // Zero cross-section for particles with kin << 132 // possible abort signal from bad arithmetic << 133 if ( theDynamicParticle->GetKineticEnergy() << 134 << 135 // 131 // 136 // Get relevant information about the projec 132 // Get relevant information about the projectile and target (A, Z) and 137 // velocity of the projectile. 133 // velocity of the projectile. 138 // 134 // 139 const G4ParticleDefinition *definitionP = th 135 const G4ParticleDefinition *definitionP = theDynamicParticle->GetDefinition(); 140 G4double AP = definitionP->GetBaryonNumber 136 G4double AP = definitionP->GetBaryonNumber(); 141 G4double ZP = definitionP->GetPDGCharge(); 137 G4double ZP = definitionP->GetPDGCharge(); 142 G4double b = theDynamicParticle->GetBeta( << 138 G4double b = theDynamicParticle->Get4Momentum().beta(); 143 if (b <= 0.0 && b >= 1.0) { return 0.0; } << 144 139 145 G4double AT = G4NistManager::Instance()->G 140 G4double AT = G4NistManager::Instance()->GetAtomicMassAmu(Z); 146 G4double ZT = (G4double)Z; 141 G4double ZT = (G4double)Z; 147 G4double bmin = thePhotonSpectrum->GetCloses 142 G4double bmin = thePhotonSpectrum->GetClosestApproach(AP, ZP, AT, ZT, b); 148 // 143 // 149 // 144 // 150 // Calculate the cross-section for the proje 145 // Calculate the cross-section for the projectile and then the target. The 151 // information is returned in a G4PhysicsFre 146 // information is returned in a G4PhysicsFreeVector, which separates out the 152 // cross-sections for the E1 and E2 moments 147 // cross-sections for the E1 and E2 moments of the virtual photon field, and 153 // the energies (GDR and GQR). 148 // the energies (GDR and GQR). 154 // 149 // 155 G4PhysicsFreeVector *theProjectileCrossSecti 150 G4PhysicsFreeVector *theProjectileCrossSections = 156 GetCrossSectionForProjectile (AP, ZP, AT, 151 GetCrossSectionForProjectile (AP, ZP, AT, ZT, b, bmin); 157 G4double crossSection = 152 G4double crossSection = 158 (*theProjectileCrossSections)[0]+(*theProj 153 (*theProjectileCrossSections)[0]+(*theProjectileCrossSections)[1]; 159 delete theProjectileCrossSections; 154 delete theProjectileCrossSections; 160 G4PhysicsFreeVector *theTargetCrossSections 155 G4PhysicsFreeVector *theTargetCrossSections = 161 GetCrossSectionForTarget (AP, ZP, AT, ZT, 156 GetCrossSectionForTarget (AP, ZP, AT, ZT, b, bmin); 162 crossSection += 157 crossSection += 163 (*theTargetCrossSections)[0]+(*theTargetCr 158 (*theTargetCrossSections)[0]+(*theTargetCrossSections)[1]; 164 delete theTargetCrossSections; 159 delete theTargetCrossSections; 165 return crossSection; 160 return crossSection; 166 } 161 } 167 ////////////////////////////////////////////// 162 //////////////////////////////////////////////////////////////////////////////// 168 // 163 // 169 G4PhysicsFreeVector * 164 G4PhysicsFreeVector * 170 G4EMDissociationCrossSection::GetCrossSectionF 165 G4EMDissociationCrossSection::GetCrossSectionForProjectile (G4double AP, 171 G4double ZP, G4double /* AT */, G4double ZT, 166 G4double ZP, G4double /* AT */, G4double ZT, G4double b, G4double bmin) 172 { 167 { 173 // 168 // 174 // 169 // 175 // Use Wilson et al's approach to calculate th 170 // Use Wilson et al's approach to calculate the cross-sections due to the E1 176 // and E2 moments of the field at the giant di 171 // and E2 moments of the field at the giant dipole and quadrupole resonances 177 // respectively, Note that the algorithm is t 172 // respectively, Note that the algorithm is traditionally applied to the 178 // EMD break-up of the projectile in the field 173 // EMD break-up of the projectile in the field of the target, as is implemented 179 // here. 174 // here. 180 // 175 // 181 // Initialise variables and calculate the ener 176 // Initialise variables and calculate the energies for the GDR and GQR. 182 // 177 // 183 G4double AProot3 = G4Pow::GetInstance()->A13 << 178 G4double AProot3 = G4Pow::GetInstance()->powA(AP,1.0/3.0); 184 G4double u = 3.0 * J / Qprime / AProot 179 G4double u = 3.0 * J / Qprime / AProot3; 185 G4double R0 = r0 * AProot3; 180 G4double R0 = r0 * AProot3; 186 G4double E_GDR = hbarc / std::sqrt(0.7*amu_ 181 G4double E_GDR = hbarc / std::sqrt(0.7*amu_c2*R0*R0/8.0/J* 187 (1.0 + u - (1.0 + epsilon + 3.0*u)/(1.0 + 182 (1.0 + u - (1.0 + epsilon + 3.0*u)/(1.0 + epsilon + u)*epsilon)); 188 G4double E_GQR = 63.0 * MeV / AProot3; 183 G4double E_GQR = 63.0 * MeV / AProot3; 189 // 184 // 190 // 185 // 191 // Determine the virtual photon spectra at the 186 // Determine the virtual photon spectra at these energies. 192 // 187 // 193 G4double ZTsq = ZT * ZT; 188 G4double ZTsq = ZT * ZT; 194 G4double nE1 = ZTsq * 189 G4double nE1 = ZTsq * 195 thePhotonSpectrum->GetGeneralE1Spectrum(E_ 190 thePhotonSpectrum->GetGeneralE1Spectrum(E_GDR, b, bmin); 196 G4double nE2 = ZTsq * 191 G4double nE2 = ZTsq * 197 thePhotonSpectrum->GetGeneralE2Spectrum(E_ 192 thePhotonSpectrum->GetGeneralE2Spectrum(E_GQR, b, bmin); 198 // 193 // 199 // 194 // 200 // Now calculate the cross-section of the proj 195 // Now calculate the cross-section of the projectile for interaction with the 201 // E1 and E2 fields. 196 // E1 and E2 fields. 202 // 197 // 203 G4double sE1 = 60.0 * millibarn * MeV * (AP- 198 G4double sE1 = 60.0 * millibarn * MeV * (AP-ZP)*ZP/AP; 204 G4double sE2 = 0.22 * microbarn / MeV * ZP * 199 G4double sE2 = 0.22 * microbarn / MeV * ZP * AProot3 * AProot3; 205 if (AP > 100.0) sE2 *= 0.9; 200 if (AP > 100.0) sE2 *= 0.9; 206 else if (AP > 40.0) sE2 *= 0.6; 201 else if (AP > 40.0) sE2 *= 0.6; 207 else sE2 *= 0.3; 202 else sE2 *= 0.3; 208 // 203 // 209 // 204 // 210 // ... and multiply with the intensity of the 205 // ... and multiply with the intensity of the virtual photon spectra to get 211 // the probability of interaction. 206 // the probability of interaction. 212 // 207 // 213 G4PhysicsFreeVector *theCrossSectionVector = 208 G4PhysicsFreeVector *theCrossSectionVector = new G4PhysicsFreeVector(2); 214 theCrossSectionVector->PutValue(0, E_GDR, sE 209 theCrossSectionVector->PutValue(0, E_GDR, sE1*nE1); 215 theCrossSectionVector->PutValue(1, E_GQR, sE 210 theCrossSectionVector->PutValue(1, E_GQR, sE2*nE2*E_GQR*E_GQR); 216 211 217 return theCrossSectionVector; 212 return theCrossSectionVector; 218 } 213 } 219 214 220 ////////////////////////////////////////////// 215 //////////////////////////////////////////////////////////////////////////////// 221 // 216 // 222 G4PhysicsFreeVector * 217 G4PhysicsFreeVector * 223 G4EMDissociationCrossSection::GetCrossSectionF 218 G4EMDissociationCrossSection::GetCrossSectionForTarget (G4double AP, 224 G4double ZP, G4double AT, G4double ZT, G4dou 219 G4double ZP, G4double AT, G4double ZT, G4double b, G4double bmin) 225 { 220 { 226 // 221 // 227 // This is a cheaky little member function to 222 // This is a cheaky little member function to calculate the probability of 228 // EMD for the target in the field of the proj 223 // EMD for the target in the field of the projectile ... just by reversing the 229 // A and Z's for the participants. 224 // A and Z's for the participants. 230 // 225 // 231 return GetCrossSectionForProjectile (AT, ZT, 226 return GetCrossSectionForProjectile (AT, ZT, AP, ZP, b, bmin); 232 } 227 } 233 228 234 ////////////////////////////////////////////// 229 //////////////////////////////////////////////////////////////////////////////// 235 // 230 // 236 G4double 231 G4double 237 G4EMDissociationCrossSection::GetWilsonProbabi 232 G4EMDissociationCrossSection::GetWilsonProbabilityForProtonDissociation(G4double A, 238 233 G4double Z) 239 { 234 { 240 // 235 // 241 // This is a simple algorithm to choose whethe 236 // This is a simple algorithm to choose whether a proton or neutron is ejected 242 // from the nucleus in the EMD interaction. 237 // from the nucleus in the EMD interaction. 243 // 238 // 244 G4double p = 0.0; 239 G4double p = 0.0; 245 if (Z < 2.0) << 240 if (Z < 6.0) 246 p = 0.0; // To avoid to remove one proton << 247 else if (Z < 6.0) << 248 p = 0.5; 241 p = 0.5; 249 else if (Z < 8.0) 242 else if (Z < 8.0) 250 p = 0.6; 243 p = 0.6; 251 else if (Z < 14.0) 244 else if (Z < 14.0) 252 p = 0.7; 245 p = 0.7; 253 else 246 else 254 { 247 { 255 G4double p1 = (G4double) Z / (G4double) A; 248 G4double p1 = (G4double) Z / (G4double) A; 256 G4double p2 = 1.95*G4Exp(-0.075*Z); 249 G4double p2 = 1.95*G4Exp(-0.075*Z); 257 if (p1 < p2) p = p1; 250 if (p1 < p2) p = p1; 258 else p = p2; 251 else p = p2; 259 } 252 } 260 253 261 return p; 254 return p; 262 } 255 } 263 256