[819] | 1 | // |
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| 2 | // ******************************************************************** |
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| 3 | // * License and Disclaimer * |
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| 4 | // * * |
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| 5 | // * The Geant4 software is copyright of the Copyright Holders of * |
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| 6 | // * the Geant4 Collaboration. It is provided under the terms and * |
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| 7 | // * conditions of the Geant4 Software License, included in the file * |
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| 8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
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| 9 | // * include a list of copyright holders. * |
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| 10 | // * * |
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| 11 | // * Neither the authors of this software system, nor their employing * |
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| 12 | // * institutes,nor the agencies providing financial support for this * |
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| 13 | // * work make any representation or warranty, express or implied, * |
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| 14 | // * regarding this software system or assume any liability for its * |
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| 15 | // * use. Please see the license in the file LICENSE and URL above * |
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| 16 | // * for the full disclaimer and the limitation of liability. * |
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| 17 | // * * |
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| 18 | // * This code implementation is the result of the scientific and * |
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| 19 | // * technical work of the GEANT4 collaboration. * |
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| 20 | // * * |
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| 21 | // * Parts of this code which have been developed by QinetiQ Ltd * |
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| 22 | // * under contract to the European Space Agency (ESA) are the * |
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| 23 | // * intellectual property of ESA. Rights to use, copy, modify and * |
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| 24 | // * redistribute this software for general public use are granted * |
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| 25 | // * in compliance with any licensing, distribution and development * |
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| 26 | // * policy adopted by the Geant4 Collaboration. This code has been * |
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| 27 | // * written by QinetiQ Ltd for the European Space Agency, under ESA * |
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| 28 | // * contract 17191/03/NL/LvH (Aurora Programme). * |
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| 29 | // * * |
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| 30 | // * By using, copying, modifying or distributing the software (or * |
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| 31 | // * any work based on the software) you agree to acknowledge its * |
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| 32 | // * use in resulting scientific publications, and indicate your * |
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| 33 | // * acceptance of all terms of the Geant4 Software license. * |
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| 34 | // ******************************************************************** |
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| 35 | // |
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| 36 | // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 37 | // |
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| 38 | // MODULE: G4TripathiLightCrossSection.cc |
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| 39 | // |
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| 40 | // Version: B.1 |
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| 41 | // Date: 15/04/04 |
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| 42 | // Author: P R Truscott |
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| 43 | // Organisation: QinetiQ Ltd, UK |
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| 44 | // Customer: ESA/ESTEC, NOORDWIJK |
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| 45 | // Contract: 17191/03/NL/LvH |
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| 46 | // |
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| 47 | // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 48 | // |
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| 49 | // CHANGE HISTORY |
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| 50 | // -------------- |
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| 51 | // |
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| 52 | // 6 October 2003, P R Truscott, QinetiQ Ltd, UK |
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| 53 | // Created. |
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| 54 | // |
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| 55 | // 15 March 2004, P R Truscott, QinetiQ Ltd, UK |
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| 56 | // Beta release |
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| 57 | // |
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| 58 | // %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% |
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| 59 | /////////////////////////////////////////////////////////////////////////////// |
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| 60 | // |
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| 61 | #include "G4TripathiLightCrossSection.hh" |
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| 62 | #include "G4WilsonRadius.hh" |
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| 63 | #include "G4ParticleTable.hh" |
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| 64 | #include "G4IonTable.hh" |
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| 65 | |
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| 66 | /////////////////////////////////////////////////////////////////////////////// |
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| 67 | // |
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| 68 | G4TripathiLightCrossSection::G4TripathiLightCrossSection () |
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| 69 | { |
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| 70 | // |
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| 71 | // |
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| 72 | // Constructor only needs to instantiate the object which provides functions |
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| 73 | // to calculate the nuclear radius, and some other constants used to |
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| 74 | // calculate cross-sections. |
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| 75 | // |
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| 76 | theWilsonRadius = new G4WilsonRadius(); |
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| 77 | r_0 = 1.1 * fermi; |
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| 78 | third = 1.0/3.0; |
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| 79 | // |
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| 80 | // |
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| 81 | // The following variable is set to true if |
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| 82 | // G4TripathiLightCrossSection::GetCrossSection is going to be called from |
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| 83 | // within G4TripathiLightCrossSection::GetCrossSection to check whether the |
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| 84 | // cross-section is behaviing anomalously in the low-energy region. |
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| 85 | // |
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| 86 | lowEnergyCheck = false; |
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| 87 | } |
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| 88 | /////////////////////////////////////////////////////////////////////////////// |
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| 89 | // |
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| 90 | G4TripathiLightCrossSection::~G4TripathiLightCrossSection () |
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| 91 | { |
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| 92 | // |
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| 93 | // |
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| 94 | // Destructor just needs to delete the pointer to the G4WilsonRadius object. |
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| 95 | // |
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| 96 | delete theWilsonRadius; |
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| 97 | } |
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| 98 | /////////////////////////////////////////////////////////////////////////////// |
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| 99 | // |
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| 100 | G4bool G4TripathiLightCrossSection::IsApplicable |
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| 101 | (const G4DynamicParticle* theProjectile, const G4Element* theTarget) |
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| 102 | { |
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| 103 | return IsZAApplicable(theProjectile, theTarget->GetZ(), theTarget->GetN()); |
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| 104 | } |
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| 105 | |
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| 106 | |
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| 107 | G4bool G4TripathiLightCrossSection::IsZAApplicable |
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| 108 | (const G4DynamicParticle* theProjectile, G4double ZZ, G4double AA) |
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| 109 | { |
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| 110 | G4bool result = false; |
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| 111 | const G4double AT = AA; |
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| 112 | const G4double ZT = ZZ; |
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| 113 | const G4double ZP = theProjectile->GetDefinition()->GetPDGCharge(); |
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| 114 | const G4double AP = theProjectile->GetDefinition()->GetBaryonNumber(); |
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| 115 | if (theProjectile->GetKineticEnergy()/ |
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| 116 | theProjectile->GetDefinition()->GetBaryonNumber()<10.0*GeV && |
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| 117 | ((AT==1 && ZT==1) || (AP==1 && ZP==1) || |
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| 118 | (AT==1 && ZT==0) || (AP==1 && ZP==0) || |
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| 119 | (AT==2 && ZT==1) || (AP==2 && ZP==1) || |
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| 120 | (AT==3 && ZT==2) || (AP==3 && ZP==2) || |
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| 121 | (AT==4 && ZT==2) || (AP==4 && ZP==2))) result = true; |
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| 122 | return result; |
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| 123 | } |
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| 124 | /////////////////////////////////////////////////////////////////////////////// |
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| 125 | // |
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| 126 | G4double G4TripathiLightCrossSection::GetIsoZACrossSection |
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| 127 | (const G4DynamicParticle* theProjectile, G4double ZZ, G4double AA, |
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| 128 | G4double /*theTemperature*/) |
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| 129 | { |
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| 130 | // |
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| 131 | // Initialise the result. |
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| 132 | G4double result = 0.0; |
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| 133 | // |
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| 134 | // |
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| 135 | // Get details of the projectile and target (nucleon number, atomic number, |
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| 136 | // kinetic enery and energy/nucleon. |
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| 137 | // |
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| 138 | const G4double AT = AA; |
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| 139 | const G4double ZT = ZZ; |
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| 140 | const G4double EA = theProjectile->GetKineticEnergy()/MeV; |
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| 141 | const G4double AP = theProjectile->GetDefinition()->GetBaryonNumber(); |
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| 142 | const G4double ZP = theProjectile->GetDefinition()->GetPDGCharge(); |
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| 143 | G4double E = EA / AP; |
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| 144 | // |
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| 145 | // |
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| 146 | // Determine target mass and energy within the centre-of-mass frame. |
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| 147 | // |
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| 148 | G4double mT = G4ParticleTable::GetParticleTable() |
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| 149 | ->GetIonTable() |
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| 150 | ->GetIonMass(static_cast<G4int>(ZT), static_cast<G4int>(AT)); |
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| 151 | G4LorentzVector pT(0.0, 0.0, 0.0, mT); |
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| 152 | G4LorentzVector pP(theProjectile->Get4Momentum()); |
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| 153 | pT = pT + pP; |
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| 154 | G4double E_cm = (pT.mag()-mT-pP.m())/MeV; |
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| 155 | // |
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| 156 | // |
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| 157 | // Determine nuclear radii. Note that the r_p and r_T are defined differently |
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| 158 | // from Wilson et al. |
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| 159 | // |
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| 160 | G4WilsonRadius theWilsonNuclearRadius; |
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| 161 | G4double r_rms_p = theWilsonRadius->GetWilsonRMSRadius(AP); |
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| 162 | G4double r_rms_t = theWilsonRadius->GetWilsonRMSRadius(AT); |
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| 163 | |
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| 164 | G4double r_p = 1.29*r_rms_p; |
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| 165 | G4double r_t = 1.29*r_rms_t; |
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| 166 | |
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| 167 | G4double Radius = (r_p + r_t)/fermi + 1.2*(std::pow(AT, third) + std::pow(AP, third))/ |
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| 168 | std::pow(E_cm, third); |
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| 169 | |
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| 170 | G4double B = 1.44 * ZP * ZT / Radius; |
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| 171 | // |
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[1228] | 172 | // |
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[819] | 173 | // Now determine other parameters associated with the parametric |
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| 174 | // formula, depending upon the projectile and target. |
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| 175 | // |
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| 176 | G4double T1 = 0.0; |
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| 177 | G4double D = 0.0; |
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| 178 | G4double G = 0.0; |
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| 179 | |
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| 180 | if ((AT==1 && ZT==1) || (AP==1 && ZP==1)) |
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| 181 | { |
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| 182 | T1 = 23.0; |
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| 183 | D = 1.85 + 0.16/(1+std::exp((500.0-E)/200.0)); |
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| 184 | } |
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| 185 | else if ((AT==1 && ZT==0) || (AP==1 && ZP==0)) |
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| 186 | { |
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| 187 | T1 = 18.0; |
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| 188 | D = 1.85 + 0.16/(1+std::exp((500.0-E)/200.0)); |
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| 189 | } |
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| 190 | else if ((AT==2 && ZT==1) || (AP==2 && ZP==1)) |
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| 191 | { |
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| 192 | T1 = 23.0; |
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| 193 | D = 1.65 + 0.1/(1+std::exp((500.0-E)/200.0)); |
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| 194 | } |
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| 195 | else if ((AT==3 && ZT==2) || (AP==3 && ZP==2)) |
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| 196 | { |
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| 197 | T1 = 40.0; |
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| 198 | D = 1.55; |
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| 199 | } |
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| 200 | else if (AP==4 && ZP==2) |
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| 201 | { |
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| 202 | if (AT==4 && ZT==2) {T1 = 40.0; G = 300.0;} |
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| 203 | else if (ZT==4) {T1 = 25.0; G = 300.0;} |
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| 204 | else if (ZT==7) {T1 = 40.0; G = 500.0;} |
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| 205 | else if (ZT==13) {T1 = 25.0; G = 300.0;} |
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| 206 | else if (ZT==26) {T1 = 40.0; G = 300.0;} |
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| 207 | else {T1 = 40.0; G = 75.0;} |
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| 208 | D = 2.77 - 8.0E-3*AT + 1.8E-5*AT*AT-0.8/(1.0+std::exp((250.0-E)/G)); |
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| 209 | } |
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| 210 | else if (AT==4 && ZT==2) |
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| 211 | { |
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| 212 | if (AP==4 && ZP==2) {T1 = 40.0; G = 300.0;} |
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| 213 | else if (ZP==4) {T1 = 25.0; G = 300.0;} |
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| 214 | else if (ZP==7) {T1 = 40.0; G = 500.0;} |
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| 215 | else if (ZP==13) {T1 = 25.0; G = 300.0;} |
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| 216 | else if (ZP==26) {T1 = 40.0; G = 300.0;} |
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| 217 | else {T1 = 40.0; G = 75.0;} |
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| 218 | D = 2.77 - 8.0E-3*AP + 1.8E-5*AP*AP-0.8/(1.0+std::exp((250.0-E)/G)); |
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| 219 | } |
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| 220 | // |
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| 221 | // |
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| 222 | // C_E, S, deltaE, X1, S_L and X_m correspond directly with the original |
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| 223 | // formulae of Tripathi et al in his report. |
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| 224 | // |
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| 225 | G4double C_E = D*(1.0-std::exp(-E/T1)) - |
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| 226 | 0.292*std::exp(-E/792.0)*std::cos(0.229*std::pow(E,0.453)); |
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| 227 | |
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| 228 | G4double S = std::pow(AP,third)*std::pow(AT,third)/(std::pow(AP,third) + std::pow(AT,third)); |
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| 229 | |
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| 230 | G4double deltaE = 0.0; |
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| 231 | G4double X1 = 0.0; |
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| 232 | if (AT >= AP) |
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| 233 | { |
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| 234 | deltaE = 1.85*S + 0.16*S/std::pow(E_cm,third) - C_E + 0.91*(AT-2.0*ZT)*ZP/AT/AP; |
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| 235 | X1 = 2.83 - 3.1E-2*AT + 1.7E-4*AT*AT; |
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| 236 | } |
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| 237 | else |
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| 238 | { |
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| 239 | deltaE = 1.85*S + 0.16*S/std::pow(E_cm,third) - C_E + 0.91*(AP-2.0*ZP)*ZT/AT/AP; |
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| 240 | X1 = 2.83 - 3.1E-2*AP + 1.7E-4*AP*AP; |
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| 241 | } |
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| 242 | G4double S_L = 1.2 + 1.6*(1.0-std::exp(-E/15.0)); |
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| 243 | G4double X_m = 1.0 - X1*std::exp(-E/X1*S_L); |
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| 244 | // |
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| 245 | // |
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| 246 | // R_c is also highly dependent upon the A and Z of the projectile and |
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| 247 | // target. |
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| 248 | // |
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| 249 | G4double R_c = 1.0; |
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| 250 | if (AP==1 && ZP==1) |
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| 251 | { |
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| 252 | if (AT==2 && ZT==1) R_c = 13.5; |
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| 253 | else if (AT==3 && ZT==2) R_c = 21.0; |
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| 254 | else if (AT==4 && ZT==2) R_c = 27.0; |
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| 255 | else if (ZT==3) R_c = 2.2; |
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| 256 | } |
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| 257 | else if (AT==1 && ZT==1) |
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| 258 | { |
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| 259 | if (AP==2 && ZP==1) R_c = 13.5; |
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| 260 | else if (AP==3 && ZP==2) R_c = 21.0; |
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| 261 | else if (AP==4 && ZP==2) R_c = 27.0; |
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| 262 | else if (ZP==3) R_c = 2.2; |
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| 263 | } |
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| 264 | else if (AP==2 && ZP==1) |
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| 265 | { |
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| 266 | if (AT==2 && ZT==1) R_c = 13.5; |
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| 267 | else if (AT==4 && ZT==2) R_c = 13.5; |
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| 268 | else if (AT==12 && ZT==6) R_c = 6.0; |
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| 269 | } |
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| 270 | else if (AT==2 && ZT==1) |
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| 271 | { |
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| 272 | if (AP==2 && ZP==1) R_c = 13.5; |
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| 273 | else if (AP==4 && ZP==2) R_c = 13.5; |
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| 274 | else if (AP==12 && ZP==6) R_c = 6.0; |
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| 275 | } |
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| 276 | else if ((AP==4 && ZP==2 && (ZT==73 || ZT==79)) || |
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| 277 | (AT==4 && ZT==2 && (ZP==73 || ZP==79))) R_c = 0.6; |
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| 278 | // |
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| 279 | // |
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| 280 | // Find the total cross-section. Check that it's value is positive, and if |
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| 281 | // the energy is less that 10 MeV/nuc, find out if the cross-section is |
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| 282 | // increasing with decreasing energy. If so this is a sign that the function |
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| 283 | // is behaving badly at low energies, and the cross-section should be |
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| 284 | // set to zero. |
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| 285 | // |
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| 286 | result = pi * r_0*r_0 * |
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| 287 | std::pow((std::pow(AT,third) + std::pow(AP,third) + deltaE),2.0) * |
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| 288 | (1.0 - R_c*B/E_cm) * X_m; |
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| 289 | if (!lowEnergyCheck) |
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| 290 | { |
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[1228] | 291 | if (result < 0.0) |
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| 292 | result = 0.0; |
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[819] | 293 | else if (E < 6.0*MeV) |
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| 294 | { |
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| 295 | G4double f = 0.95; |
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| 296 | G4DynamicParticle slowerProjectile = *theProjectile; |
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| 297 | slowerProjectile.SetKineticEnergy(f * EA * MeV); |
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[1228] | 298 | // G4TripathiLightCrossSection theTripathiLightCrossSection; // MHM 20090824 Not needed |
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| 299 | // theTripathiLightCrossSection.SetLowEnergyCheck(true); |
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| 300 | G4bool savelowenergy=lowEnergyCheck; |
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| 301 | SetLowEnergyCheck(true); |
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[819] | 302 | G4double resultp = |
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[1228] | 303 | GetIsoZACrossSection(&slowerProjectile, ZZ, AA, 0.0); |
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| 304 | SetLowEnergyCheck(savelowenergy); |
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[819] | 305 | if (resultp >result) result = 0.0; |
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| 306 | } |
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| 307 | } |
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[1228] | 308 | |
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[819] | 309 | return result; |
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| 310 | } |
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| 311 | |
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| 312 | |
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| 313 | G4double G4TripathiLightCrossSection::GetCrossSection |
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| 314 | (const G4DynamicParticle* theProjectile, const G4Element* theTarget, |
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| 315 | G4double theTemperature) |
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| 316 | { |
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| 317 | G4int nIso = theTarget->GetNumberOfIsotopes(); |
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| 318 | G4double xsection = 0; |
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| 319 | |
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| 320 | if (nIso) { |
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| 321 | G4double sig; |
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| 322 | G4IsotopeVector* isoVector = theTarget->GetIsotopeVector(); |
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| 323 | G4double* abundVector = theTarget->GetRelativeAbundanceVector(); |
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| 324 | G4double ZZ; |
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| 325 | G4double AA; |
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| 326 | |
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| 327 | for (G4int i = 0; i < nIso; i++) { |
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| 328 | ZZ = G4double( (*isoVector)[i]->GetZ() ); |
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| 329 | AA = G4double( (*isoVector)[i]->GetN() ); |
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| 330 | sig = GetIsoZACrossSection(theProjectile, ZZ, AA, theTemperature); |
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| 331 | xsection += sig*abundVector[i]; |
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| 332 | } |
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| 333 | |
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| 334 | } else { |
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| 335 | xsection = |
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| 336 | GetIsoZACrossSection(theProjectile, theTarget->GetZ(), theTarget->GetN(), |
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| 337 | theTemperature); |
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| 338 | } |
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| 339 | |
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| 340 | return xsection; |
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| 341 | } |
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| 342 | |
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| 343 | |
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| 344 | /////////////////////////////////////////////////////////////////////////////// |
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| 345 | // |
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| 346 | void G4TripathiLightCrossSection::SetLowEnergyCheck (G4bool aLowEnergyCheck) |
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| 347 | { |
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| 348 | lowEnergyCheck = aLowEnergyCheck; |
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| 349 | } |
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| 350 | /////////////////////////////////////////////////////////////////////////////// |
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| 351 | // |
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