[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 | // * By using, copying, modifying or distributing the software (or * |
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| 21 | // * any work based on the software) you agree to acknowledge its * |
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| 22 | // * use in resulting scientific publications, and indicate your * |
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| 23 | // * acceptance of all terms of the Geant4 Software license. * |
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| 24 | // ******************************************************************** |
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| 25 | // |
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| 26 | // $Id: G4RPGAntiNeutronInelastic.cc,v 1.1 2007/07/18 21:04:20 dennis Exp $ |
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[1228] | 27 | // GEANT4 tag $Name: geant4-09-03 $ |
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[819] | 28 | // |
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| 29 | |
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| 30 | #include "G4RPGAntiNeutronInelastic.hh" |
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| 31 | #include "Randomize.hh" |
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| 32 | |
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| 33 | G4HadFinalState* |
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| 34 | G4RPGAntiNeutronInelastic::ApplyYourself( const G4HadProjectile &aTrack, |
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| 35 | G4Nucleus &targetNucleus ) |
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| 36 | { |
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| 37 | const G4HadProjectile *originalIncident = &aTrack; |
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| 38 | |
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| 39 | // create the target particle |
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| 40 | |
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| 41 | G4DynamicParticle *originalTarget = targetNucleus.ReturnTargetParticle(); |
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| 42 | |
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| 43 | if( verboseLevel > 1 ) |
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| 44 | { |
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| 45 | const G4Material *targetMaterial = aTrack.GetMaterial(); |
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| 46 | G4cout << "G4RPGAntiNeutronInelastic::ApplyYourself called" << G4endl; |
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| 47 | G4cout << "kinetic energy = " << originalIncident->GetKineticEnergy()/MeV << "MeV, "; |
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| 48 | G4cout << "target material = " << targetMaterial->GetName() << ", "; |
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| 49 | G4cout << "target particle = " << originalTarget->GetDefinition()->GetParticleName() |
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| 50 | << G4endl; |
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| 51 | } |
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| 52 | // |
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| 53 | // Fermi motion and evaporation |
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| 54 | // As of Geant3, the Fermi energy calculation had not been Done |
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| 55 | // |
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| 56 | G4double ek = originalIncident->GetKineticEnergy()/MeV; |
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| 57 | G4double amas = originalIncident->GetDefinition()->GetPDGMass()/MeV; |
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| 58 | G4ReactionProduct modifiedOriginal; |
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| 59 | modifiedOriginal = *originalIncident; |
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| 60 | |
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| 61 | G4double tkin = targetNucleus.Cinema( ek ); |
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| 62 | ek += tkin; |
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| 63 | modifiedOriginal.SetKineticEnergy( ek*MeV ); |
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| 64 | G4double et = ek + amas; |
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| 65 | G4double p = std::sqrt( std::abs((et-amas)*(et+amas)) ); |
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| 66 | G4double pp = modifiedOriginal.GetMomentum().mag()/MeV; |
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| 67 | if( pp > 0.0 ) |
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| 68 | { |
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| 69 | G4ThreeVector momentum = modifiedOriginal.GetMomentum(); |
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| 70 | modifiedOriginal.SetMomentum( momentum * (p/pp) ); |
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| 71 | } |
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| 72 | // |
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| 73 | // calculate black track energies |
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| 74 | // |
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| 75 | tkin = targetNucleus.EvaporationEffects( ek ); |
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| 76 | ek -= tkin; |
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| 77 | modifiedOriginal.SetKineticEnergy( ek*MeV ); |
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| 78 | et = ek + amas; |
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| 79 | p = std::sqrt( std::abs((et-amas)*(et+amas)) ); |
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| 80 | pp = modifiedOriginal.GetMomentum().mag()/MeV; |
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| 81 | if( pp > 0.0 ) |
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| 82 | { |
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| 83 | G4ThreeVector momentum = modifiedOriginal.GetMomentum(); |
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| 84 | modifiedOriginal.SetMomentum( momentum * (p/pp) ); |
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| 85 | } |
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| 86 | |
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| 87 | G4ReactionProduct currentParticle = modifiedOriginal; |
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| 88 | G4ReactionProduct targetParticle; |
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| 89 | targetParticle = *originalTarget; |
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| 90 | currentParticle.SetSide( 1 ); // incident always goes in forward hemisphere |
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| 91 | targetParticle.SetSide( -1 ); // target always goes in backward hemisphere |
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| 92 | G4bool incidentHasChanged = false; |
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| 93 | G4bool targetHasChanged = false; |
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| 94 | G4bool quasiElastic = false; |
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| 95 | G4FastVector<G4ReactionProduct,GHADLISTSIZE> vec; // vec will contain the secondary particles |
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| 96 | G4int vecLen = 0; |
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| 97 | vec.Initialize( 0 ); |
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| 98 | |
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| 99 | const G4double cutOff = 0.1*MeV; |
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| 100 | const G4double anni = std::min( 1.3*currentParticle.GetTotalMomentum()/GeV, 0.4 ); |
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| 101 | |
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| 102 | if( (currentParticle.GetKineticEnergy()/MeV > cutOff) || |
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| 103 | (G4UniformRand() > anni) ) |
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| 104 | Cascade( vec, vecLen, |
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| 105 | originalIncident, currentParticle, targetParticle, |
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| 106 | incidentHasChanged, targetHasChanged, quasiElastic ); |
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| 107 | else |
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| 108 | quasiElastic = true; |
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| 109 | |
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| 110 | CalculateMomenta( vec, vecLen, |
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| 111 | originalIncident, originalTarget, modifiedOriginal, |
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| 112 | targetNucleus, currentParticle, targetParticle, |
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| 113 | incidentHasChanged, targetHasChanged, quasiElastic ); |
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| 114 | |
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| 115 | SetUpChange( vec, vecLen, |
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| 116 | currentParticle, targetParticle, |
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| 117 | incidentHasChanged ); |
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| 118 | |
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| 119 | delete originalTarget; |
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| 120 | return &theParticleChange; |
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| 121 | } |
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| 122 | |
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| 123 | |
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| 124 | void G4RPGAntiNeutronInelastic::Cascade( |
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| 125 | G4FastVector<G4ReactionProduct,GHADLISTSIZE> &vec, |
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| 126 | G4int& vecLen, |
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| 127 | const G4HadProjectile *originalIncident, |
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| 128 | G4ReactionProduct ¤tParticle, |
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| 129 | G4ReactionProduct &targetParticle, |
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| 130 | G4bool &incidentHasChanged, |
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| 131 | G4bool &targetHasChanged, |
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| 132 | G4bool &quasiElastic ) |
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| 133 | { |
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| 134 | // Derived from H. Fesefeldt's original FORTRAN code CASNB |
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| 135 | // AntiNeutron undergoes interaction with nucleon within a nucleus. Check if it is |
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| 136 | // energetically possible to produce pions/kaons. In not, assume nuclear excitation |
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| 137 | // occurs and input particle is degraded in energy. No other particles are produced. |
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| 138 | // If reaction is possible, find the correct number of pions/protons/neutrons |
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| 139 | // produced using an interpolation to multiplicity data. Replace some pions or |
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| 140 | // protons/neutrons by kaons or strange baryons according to the average |
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| 141 | // multiplicity per Inelastic reaction. |
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| 142 | |
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| 143 | const G4double mOriginal = originalIncident->GetDefinition()->GetPDGMass()/MeV; |
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| 144 | const G4double etOriginal = originalIncident->GetTotalEnergy()/MeV; |
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| 145 | const G4double pOriginal = originalIncident->GetTotalMomentum()/MeV; |
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| 146 | const G4double targetMass = targetParticle.GetMass()/MeV; |
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| 147 | G4double centerofmassEnergy = std::sqrt( mOriginal*mOriginal + |
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| 148 | targetMass*targetMass + |
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| 149 | 2.0*targetMass*etOriginal ); |
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| 150 | G4double availableEnergy = centerofmassEnergy-(targetMass+mOriginal); |
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| 151 | |
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| 152 | static G4bool first = true; |
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| 153 | const G4int numMul = 1200; |
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| 154 | const G4int numMulA = 400; |
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| 155 | const G4int numSec = 60; |
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| 156 | static G4double protmul[numMul], protnorm[numSec]; // proton constants |
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| 157 | static G4double neutmul[numMul], neutnorm[numSec]; // neutron constants |
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| 158 | static G4double protmulA[numMulA], protnormA[numSec]; // proton constants |
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| 159 | static G4double neutmulA[numMulA], neutnormA[numSec]; // neutron constants |
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| 160 | // np = number of pi+, nm = number of pi-, nz = number of pi0 |
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| 161 | G4int counter, nt=0, np=0, nm=0, nz=0; |
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| 162 | G4double test; |
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| 163 | const G4double c = 1.25; |
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| 164 | const G4double b[] = { 0.70, 0.70 }; |
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| 165 | if( first ) // compute normalization constants, this will only be Done once |
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| 166 | { |
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| 167 | first = false; |
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| 168 | G4int i; |
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| 169 | for( i=0; i<numMul; ++i )protmul[i] = 0.0; |
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| 170 | for( i=0; i<numSec; ++i )protnorm[i] = 0.0; |
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| 171 | counter = -1; |
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| 172 | for( np=0; np<(numSec/3); ++np ) |
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| 173 | { |
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| 174 | for( nm=std::max(0,np-2); nm<=np; ++nm ) |
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| 175 | { |
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| 176 | for( nz=0; nz<numSec/3; ++nz ) |
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| 177 | { |
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| 178 | if( ++counter < numMul ) |
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| 179 | { |
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| 180 | nt = np+nm+nz; |
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| 181 | if( nt>0 && nt<=numSec ) |
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| 182 | { |
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| 183 | protmul[counter] = Pmltpc(np,nm,nz,nt,b[0],c); |
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| 184 | protnorm[nt-1] += protmul[counter]; |
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| 185 | } |
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| 186 | } |
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| 187 | } |
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| 188 | } |
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| 189 | } |
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| 190 | for( i=0; i<numMul; ++i )neutmul[i] = 0.0; |
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| 191 | for( i=0; i<numSec; ++i )neutnorm[i] = 0.0; |
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| 192 | counter = -1; |
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| 193 | for( np=0; np<numSec/3; ++np ) |
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| 194 | { |
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| 195 | for( nm=std::max(0,np-1); nm<=(np+1); ++nm ) |
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| 196 | { |
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| 197 | for( nz=0; nz<numSec/3; ++nz ) |
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| 198 | { |
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| 199 | if( ++counter < numMul ) |
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| 200 | { |
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| 201 | nt = np+nm+nz; |
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| 202 | if( (nt>0) && (nt<=numSec) ) |
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| 203 | { |
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| 204 | neutmul[counter] = Pmltpc(np,nm,nz,nt,b[1],c); |
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| 205 | neutnorm[nt-1] += neutmul[counter]; |
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| 206 | } |
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| 207 | } |
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| 208 | } |
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| 209 | } |
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| 210 | } |
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| 211 | for( i=0; i<numSec; ++i ) |
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| 212 | { |
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| 213 | if( protnorm[i] > 0.0 )protnorm[i] = 1.0/protnorm[i]; |
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| 214 | if( neutnorm[i] > 0.0 )neutnorm[i] = 1.0/neutnorm[i]; |
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| 215 | } |
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| 216 | // |
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| 217 | // do the same for annihilation channels |
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| 218 | // |
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| 219 | for( i=0; i<numMulA; ++i )protmulA[i] = 0.0; |
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| 220 | for( i=0; i<numSec; ++i )protnormA[i] = 0.0; |
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| 221 | counter = -1; |
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| 222 | for( np=1; np<(numSec/3); ++np ) |
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| 223 | { |
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| 224 | nm = np-1; |
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| 225 | for( nz=0; nz<numSec/3; ++nz ) |
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| 226 | { |
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| 227 | if( ++counter < numMulA ) |
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| 228 | { |
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| 229 | nt = np+nm+nz; |
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| 230 | if( nt>1 && nt<=numSec ) |
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| 231 | { |
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| 232 | protmulA[counter] = Pmltpc(np,nm,nz,nt,b[0],c); |
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| 233 | protnormA[nt-1] += protmulA[counter]; |
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| 234 | } |
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| 235 | } |
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| 236 | } |
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| 237 | } |
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| 238 | for( i=0; i<numMulA; ++i )neutmulA[i] = 0.0; |
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| 239 | for( i=0; i<numSec; ++i )neutnormA[i] = 0.0; |
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| 240 | counter = -1; |
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| 241 | for( np=0; np<numSec/3; ++np ) |
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| 242 | { |
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| 243 | nm = np; |
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| 244 | for( nz=0; nz<numSec/3; ++nz ) |
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| 245 | { |
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| 246 | if( ++counter < numMulA ) |
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| 247 | { |
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| 248 | nt = np+nm+nz; |
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| 249 | if( nt>1 && nt<=numSec ) |
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| 250 | { |
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| 251 | neutmulA[counter] = Pmltpc(np,nm,nz,nt,b[1],c); |
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| 252 | neutnormA[nt-1] += neutmulA[counter]; |
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| 253 | } |
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| 254 | } |
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| 255 | } |
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| 256 | } |
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| 257 | for( i=0; i<numSec; ++i ) |
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| 258 | { |
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| 259 | if( protnormA[i] > 0.0 )protnormA[i] = 1.0/protnormA[i]; |
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| 260 | if( neutnormA[i] > 0.0 )neutnormA[i] = 1.0/neutnormA[i]; |
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| 261 | } |
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| 262 | } // end of initialization |
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| 263 | const G4double expxu = 82.; // upper bound for arg. of exp |
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| 264 | const G4double expxl = -expxu; // lower bound for arg. of exp |
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| 265 | G4ParticleDefinition *aNeutron = G4Neutron::Neutron(); |
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| 266 | G4ParticleDefinition *aProton = G4Proton::Proton(); |
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| 267 | G4ParticleDefinition *anAntiProton = G4AntiProton::AntiProton(); |
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| 268 | G4ParticleDefinition *aPiPlus = G4PionPlus::PionPlus(); |
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| 269 | |
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| 270 | // energetically possible to produce pion(s) --> inelastic scattering |
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| 271 | // otherwise quasi-elastic scattering |
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| 272 | |
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| 273 | const G4double anhl[] = {1.00,1.00,1.00,1.00,1.00,1.00,1.00,1.00,0.97,0.88, |
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| 274 | 0.85,0.81,0.75,0.64,0.64,0.55,0.55,0.45,0.47,0.40, |
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| 275 | 0.39,0.36,0.33,0.10,0.01}; |
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| 276 | G4int iplab = G4int( pOriginal/GeV*10.0 ); |
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| 277 | if( iplab > 9 )iplab = G4int( (pOriginal/GeV- 1.0)*5.0 ) + 10; |
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| 278 | if( iplab > 14 )iplab = G4int( pOriginal/GeV- 2.0 ) + 15; |
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| 279 | if( iplab > 22 )iplab = G4int( (pOriginal/GeV-10.0)/10.0 ) + 23; |
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| 280 | if( iplab > 24 )iplab = 24; |
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| 281 | if( G4UniformRand() > anhl[iplab] ) |
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| 282 | { |
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| 283 | if( availableEnergy <= aPiPlus->GetPDGMass()/MeV ) |
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| 284 | { |
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| 285 | quasiElastic = true; |
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| 286 | return; |
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| 287 | } |
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| 288 | G4int ieab = static_cast<G4int>(availableEnergy*5.0/GeV); |
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| 289 | const G4double supp[] = {0.,0.4,0.55,0.65,0.75,0.82,0.86,0.90,0.94,0.98}; |
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| 290 | G4double w0, wp, wt, wm; |
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| 291 | if( (availableEnergy < 2.0*GeV) && (G4UniformRand() >= supp[ieab]) ) |
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| 292 | { |
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| 293 | // suppress high multiplicity events at low momentum |
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| 294 | // only one pion will be produced |
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| 295 | // |
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| 296 | np = nm = nz = 0; |
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| 297 | if( targetParticle.GetDefinition() == aProton ) |
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| 298 | { |
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| 299 | test = std::exp( std::min( expxu, std::max( expxl, -(1.0+b[0])*(1.0+b[0])/(2.0*c*c) ) ) ); |
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| 300 | w0 = test; |
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| 301 | wp = test; |
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| 302 | if( G4UniformRand() < w0/(w0+wp) ) |
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| 303 | nz = 1; |
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| 304 | else |
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| 305 | np = 1; |
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| 306 | } |
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| 307 | else // target is a neutron |
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| 308 | { |
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| 309 | test = std::exp( std::min( expxu, std::max( expxl, -(1.0+b[1])*(1.0+b[1])/(2.0*c*c) ) ) ); |
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| 310 | w0 = test; |
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| 311 | wp = test; |
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| 312 | test = std::exp( std::min( expxu, std::max( expxl, -(-1.0+b[1])*(-1.0+b[1])/(2.0*c*c) ) ) ); |
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| 313 | wm = test; |
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| 314 | wt = w0+wp+wm; |
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| 315 | wp += w0; |
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| 316 | G4double ran = G4UniformRand(); |
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| 317 | if( ran < w0/wt ) |
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| 318 | nz = 1; |
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| 319 | else if( ran < wp/wt ) |
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| 320 | np = 1; |
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| 321 | else |
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| 322 | nm = 1; |
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| 323 | } |
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| 324 | } |
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| 325 | else // (availableEnergy >= 2.0*GeV) || (random number < supp[ieab]) |
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| 326 | { |
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| 327 | G4double n, anpn; |
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| 328 | GetNormalizationConstant( availableEnergy, n, anpn ); |
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| 329 | G4double ran = G4UniformRand(); |
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| 330 | G4double dum, excs = 0.0; |
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| 331 | if( targetParticle.GetDefinition() == aProton ) |
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| 332 | { |
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| 333 | counter = -1; |
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| 334 | for( np=0; np<numSec/3 && ran>=excs; ++np ) |
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| 335 | { |
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| 336 | for( nm=std::max(0,np-2); nm<=np && ran>=excs; ++nm ) |
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| 337 | { |
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| 338 | for( nz=0; nz<numSec/3 && ran>=excs; ++nz ) |
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| 339 | { |
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| 340 | if( ++counter < numMul ) |
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| 341 | { |
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| 342 | nt = np+nm+nz; |
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| 343 | if( nt > 0 ) |
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| 344 | { |
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| 345 | test = std::exp( std::min( expxu, std::max( expxl, -(pi/4.0)*(nt*nt)/(n*n) ) ) ); |
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| 346 | dum = (pi/anpn)*nt*protmul[counter]*protnorm[nt-1]/(2.0*n*n); |
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| 347 | if( std::fabs(dum) < 1.0 ) |
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| 348 | { |
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| 349 | if( test >= 1.0e-10 )excs += dum*test; |
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| 350 | } |
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| 351 | else |
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| 352 | excs += dum*test; |
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| 353 | } |
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| 354 | } |
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| 355 | } |
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| 356 | } |
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| 357 | } |
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| 358 | if( ran >= excs ) // 3 previous loops continued to the end |
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| 359 | { |
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| 360 | quasiElastic = true; |
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| 361 | return; |
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| 362 | } |
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| 363 | np--; nm--; nz--; |
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| 364 | } |
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| 365 | else // target must be a neutron |
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| 366 | { |
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| 367 | counter = -1; |
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| 368 | for( np=0; np<numSec/3 && ran>=excs; ++np ) |
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| 369 | { |
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| 370 | for( nm=std::max(0,np-1); nm<=(np+1) && ran>=excs; ++nm ) |
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| 371 | { |
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| 372 | for( nz=0; nz<numSec/3 && ran>=excs; ++nz ) |
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| 373 | { |
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| 374 | if( ++counter < numMul ) |
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| 375 | { |
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| 376 | nt = np+nm+nz; |
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| 377 | if( (nt>=1) && (nt<=numSec) ) |
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| 378 | { |
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| 379 | test = std::exp( std::min( expxu, std::max( expxl, -(pi/4.0)*(nt*nt)/(n*n) ) ) ); |
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| 380 | dum = (pi/anpn)*nt*neutmul[counter]*neutnorm[nt-1]/(2.0*n*n); |
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| 381 | if( std::fabs(dum) < 1.0 ) |
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| 382 | { |
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| 383 | if( test >= 1.0e-10 )excs += dum*test; |
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| 384 | } |
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| 385 | else |
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| 386 | excs += dum*test; |
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| 387 | } |
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| 388 | } |
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| 389 | } |
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| 390 | } |
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| 391 | } |
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| 392 | if( ran >= excs ) // 3 previous loops continued to the end |
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| 393 | { |
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| 394 | quasiElastic = true; |
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| 395 | return; |
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| 396 | } |
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| 397 | np--; nm--; nz--; |
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| 398 | } |
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| 399 | } |
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| 400 | if( targetParticle.GetDefinition() == aProton ) |
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| 401 | { |
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| 402 | switch( np-nm ) |
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| 403 | { |
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| 404 | case 1: |
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| 405 | if( G4UniformRand() < 0.5 ) |
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| 406 | { |
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| 407 | currentParticle.SetDefinitionAndUpdateE( anAntiProton ); |
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| 408 | incidentHasChanged = true; |
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| 409 | } |
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| 410 | else |
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| 411 | { |
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| 412 | targetParticle.SetDefinitionAndUpdateE( aNeutron ); |
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| 413 | targetHasChanged = true; |
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| 414 | } |
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| 415 | break; |
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| 416 | case 2: |
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| 417 | currentParticle.SetDefinitionAndUpdateE( anAntiProton ); |
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| 418 | targetParticle.SetDefinitionAndUpdateE( aNeutron ); |
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| 419 | incidentHasChanged = true; |
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| 420 | targetHasChanged = true; |
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| 421 | break; |
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| 422 | default: |
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| 423 | break; |
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| 424 | } |
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| 425 | } |
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| 426 | else // target must be a neutron |
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| 427 | { |
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| 428 | switch( np-nm ) |
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| 429 | { |
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| 430 | case 0: |
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| 431 | if( G4UniformRand() < 0.33 ) |
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| 432 | { |
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| 433 | currentParticle.SetDefinitionAndUpdateE( anAntiProton ); |
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| 434 | targetParticle.SetDefinitionAndUpdateE( aProton ); |
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| 435 | incidentHasChanged = true; |
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| 436 | targetHasChanged = true; |
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| 437 | } |
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| 438 | break; |
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| 439 | case 1: |
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| 440 | currentParticle.SetDefinitionAndUpdateE( anAntiProton ); |
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| 441 | incidentHasChanged = true; |
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| 442 | break; |
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| 443 | default: |
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| 444 | targetParticle.SetDefinitionAndUpdateE( aProton ); |
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| 445 | targetHasChanged = true; |
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| 446 | break; |
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| 447 | } |
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| 448 | } |
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| 449 | } |
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| 450 | else // random number <= anhl[iplab] |
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| 451 | { |
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| 452 | if( centerofmassEnergy <= 2*aPiPlus->GetPDGMass()/MeV ) |
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| 453 | { |
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| 454 | quasiElastic = true; |
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| 455 | return; |
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| 456 | } |
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| 457 | // |
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| 458 | // annihilation channels |
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| 459 | // |
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| 460 | G4double n, anpn; |
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| 461 | GetNormalizationConstant( -centerofmassEnergy, n, anpn ); |
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| 462 | G4double ran = G4UniformRand(); |
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| 463 | G4double dum, excs = 0.0; |
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| 464 | if( targetParticle.GetDefinition() == aProton ) |
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| 465 | { |
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| 466 | counter = -1; |
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| 467 | for( np=1; (np<numSec/3) && (ran>=excs); ++np ) |
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| 468 | { |
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| 469 | nm = np-1; |
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| 470 | for( nz=0; (nz<numSec/3) && (ran>=excs); ++nz ) |
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| 471 | { |
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| 472 | if( ++counter < numMulA ) |
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| 473 | { |
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| 474 | nt = np+nm+nz; |
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| 475 | if( nt>1 && nt<=numSec ) |
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| 476 | { |
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| 477 | test = std::exp( std::min( expxu, std::max( expxl, -(pi/4.0)*(nt*nt)/(n*n) ) ) ); |
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| 478 | dum = (pi/anpn)*nt*protmulA[counter]*protnormA[nt-1]/(2.0*n*n); |
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| 479 | if( std::fabs(dum) < 1.0 ) |
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| 480 | { |
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| 481 | if( test >= 1.0e-10 )excs += dum*test; |
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| 482 | } |
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| 483 | else |
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| 484 | excs += dum*test; |
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| 485 | } |
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| 486 | } |
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| 487 | } |
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| 488 | } |
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| 489 | } |
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| 490 | else // target must be a neutron |
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| 491 | { |
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| 492 | counter = -1; |
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| 493 | for( np=0; (np<numSec/3) && (ran>=excs); ++np ) |
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| 494 | { |
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| 495 | nm = np; |
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| 496 | for( nz=0; (nz<numSec/3) && (ran>=excs); ++nz ) |
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| 497 | { |
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| 498 | if( ++counter < numMulA ) |
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| 499 | { |
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| 500 | nt = np+nm+nz; |
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| 501 | if( (nt>1) && (nt<=numSec) ) |
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| 502 | { |
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| 503 | test = std::exp( std::min( expxu, std::max( expxl, -(pi/4.0)*(nt*nt)/(n*n) ) ) ); |
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| 504 | dum = (pi/anpn)*nt*neutmulA[counter]*neutnormA[nt-1]/(2.0*n*n); |
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| 505 | if( std::fabs(dum) < 1.0 ) |
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| 506 | { |
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| 507 | if( test >= 1.0e-10 )excs += dum*test; |
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| 508 | } |
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| 509 | else |
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| 510 | excs += dum*test; |
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| 511 | } |
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| 512 | } |
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| 513 | } |
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| 514 | } |
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| 515 | } |
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| 516 | if( ran >= excs ) // 3 previous loops continued to the end |
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| 517 | { |
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| 518 | quasiElastic = true; |
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| 519 | return; |
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| 520 | } |
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| 521 | np--; nz--; |
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| 522 | currentParticle.SetMass( 0.0 ); |
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| 523 | targetParticle.SetMass( 0.0 ); |
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| 524 | } |
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| 525 | while(np+nm+nz<3) nz++; |
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| 526 | |
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| 527 | SetUpPions( np, nm, nz, vec, vecLen ); |
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| 528 | return; |
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| 529 | } |
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| 530 | |
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| 531 | /* end of file */ |
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| 532 | |
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