[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 | // |
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[1347] | 27 | // $Id: G4CompetitiveFission.cc,v 1.14 2010/11/17 20:22:46 vnivanch Exp $ |
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| 28 | // GEANT4 tag $Name: geant4-09-04-ref-00 $ |
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[819] | 29 | // |
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| 30 | // Hadronic Process: Nuclear De-excitations |
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| 31 | // by V. Lara (Oct 1998) |
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[1055] | 32 | // |
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| 33 | // J. M. Quesada (March 2009). Bugs fixed: |
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| 34 | // - Full relativistic calculation (Lorentz boosts) |
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| 35 | // - Fission pairing energy is included in fragment excitation energies |
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| 36 | // Now Energy and momentum are conserved in fission |
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[819] | 37 | |
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| 38 | #include "G4CompetitiveFission.hh" |
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| 39 | #include "G4PairingCorrection.hh" |
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[1315] | 40 | #include "G4ParticleMomentum.hh" |
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[1347] | 41 | #include "G4Pow.hh" |
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[819] | 42 | |
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| 43 | G4CompetitiveFission::G4CompetitiveFission() : G4VEvaporationChannel("fission") |
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| 44 | { |
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| 45 | theFissionBarrierPtr = new G4FissionBarrier; |
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| 46 | MyOwnFissionBarrier = true; |
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| 47 | |
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| 48 | theFissionProbabilityPtr = new G4FissionProbability; |
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| 49 | MyOwnFissionProbability = true; |
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| 50 | |
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| 51 | theLevelDensityPtr = new G4FissionLevelDensityParameter; |
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| 52 | MyOwnLevelDensity = true; |
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| 53 | |
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| 54 | MaximalKineticEnergy = -1000.0*MeV; |
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| 55 | FissionBarrier = 0.0; |
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| 56 | FissionProbability = 0.0; |
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| 57 | LevelDensityParameter = 0.0; |
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| 58 | } |
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| 59 | |
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| 60 | G4CompetitiveFission::~G4CompetitiveFission() |
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| 61 | { |
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| 62 | if (MyOwnFissionBarrier) delete theFissionBarrierPtr; |
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| 63 | |
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| 64 | if (MyOwnFissionProbability) delete theFissionProbabilityPtr; |
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| 65 | |
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| 66 | if (MyOwnLevelDensity) delete theLevelDensityPtr; |
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| 67 | } |
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| 68 | |
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| 69 | void G4CompetitiveFission::Initialize(const G4Fragment & fragment) |
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| 70 | { |
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[1347] | 71 | G4int anA = fragment.GetA_asInt(); |
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| 72 | G4int aZ = fragment.GetZ_asInt(); |
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| 73 | G4double ExEnergy = fragment.GetExcitationEnergy() - |
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| 74 | G4PairingCorrection::GetInstance()->GetFissionPairingCorrection(anA,aZ); |
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[819] | 75 | |
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| 76 | |
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[1347] | 77 | // Saddle point excitation energy ---> A = 65 |
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| 78 | // Fission is excluded for A < 65 |
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| 79 | if (anA >= 65 && ExEnergy > 0.0) { |
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| 80 | FissionBarrier = theFissionBarrierPtr->FissionBarrier(anA,aZ,ExEnergy); |
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| 81 | MaximalKineticEnergy = ExEnergy - FissionBarrier; |
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| 82 | LevelDensityParameter = |
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| 83 | theLevelDensityPtr->LevelDensityParameter(anA,aZ,ExEnergy); |
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| 84 | FissionProbability = |
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| 85 | theFissionProbabilityPtr->EmissionProbability(fragment,MaximalKineticEnergy); |
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[819] | 86 | } |
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[1347] | 87 | else { |
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| 88 | MaximalKineticEnergy = -1000.0*MeV; |
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| 89 | LevelDensityParameter = 0.0; |
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| 90 | FissionProbability = 0.0; |
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| 91 | } |
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[819] | 92 | } |
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| 93 | |
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| 94 | G4FragmentVector * G4CompetitiveFission::BreakUp(const G4Fragment & theNucleus) |
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| 95 | { |
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[1347] | 96 | // Nucleus data |
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| 97 | // Atomic number of nucleus |
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| 98 | G4int A = theNucleus.GetA_asInt(); |
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| 99 | // Charge of nucleus |
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| 100 | G4int Z = theNucleus.GetZ_asInt(); |
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| 101 | // Excitation energy (in MeV) |
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| 102 | G4double U = theNucleus.GetExcitationEnergy() - |
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| 103 | G4PairingCorrection::GetInstance()->GetFissionPairingCorrection(A,Z); |
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| 104 | // Check that U > 0 |
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| 105 | if (U <= 0.0) { |
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| 106 | G4FragmentVector * theResult = new G4FragmentVector; |
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| 107 | theResult->push_back(new G4Fragment(theNucleus)); |
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| 108 | return theResult; |
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| 109 | } |
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[819] | 110 | |
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[1347] | 111 | // Atomic Mass of Nucleus (in MeV) |
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| 112 | G4double M = theNucleus.GetGroundStateMass(); |
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[1055] | 113 | |
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[1347] | 114 | // Nucleus Momentum |
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| 115 | G4LorentzVector theNucleusMomentum = theNucleus.GetMomentum(); |
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[1055] | 116 | |
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[1347] | 117 | // Calculate fission parameters |
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| 118 | G4FissionParameters theParameters(A,Z,U,FissionBarrier); |
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[819] | 119 | |
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[1347] | 120 | // First fragment |
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| 121 | G4int A1 = 0; |
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| 122 | G4int Z1 = 0; |
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| 123 | G4double M1 = 0.0; |
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[819] | 124 | |
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[1347] | 125 | // Second fragment |
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| 126 | G4int A2 = 0; |
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| 127 | G4int Z2 = 0; |
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| 128 | G4double M2 = 0.0; |
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[819] | 129 | |
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[1347] | 130 | G4double FragmentsExcitationEnergy = 0.0; |
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| 131 | G4double FragmentsKineticEnergy = 0.0; |
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[819] | 132 | |
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[1347] | 133 | //JMQ 04/03/09 It will be used latter to fix the bug in energy conservation |
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| 134 | G4double FissionPairingEnergy= |
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| 135 | G4PairingCorrection::GetInstance()->GetFissionPairingCorrection(A,Z); |
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[1055] | 136 | |
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[1347] | 137 | G4int Trials = 0; |
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| 138 | do { |
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[819] | 139 | |
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[1347] | 140 | // First fragment |
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| 141 | A1 = FissionAtomicNumber(A,theParameters); |
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| 142 | Z1 = FissionCharge(A,Z,A1); |
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| 143 | M1 = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIonMass(Z1,A1); |
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[819] | 144 | |
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[1347] | 145 | // Second Fragment |
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| 146 | A2 = A - A1; |
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| 147 | Z2 = Z - Z1; |
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| 148 | if (A2 < 1 || Z2 < 0) { |
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| 149 | throw G4HadronicException(__FILE__, __LINE__, |
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| 150 | "G4CompetitiveFission::BreakUp: Can't define second fragment! "); |
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| 151 | } |
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| 152 | M2 = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIonMass(Z2,A2); |
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[819] | 153 | |
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[1347] | 154 | // Check that fragment masses are less or equal than total energy |
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| 155 | if (M1 + M2 > theNucleusMomentum.e()) { |
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| 156 | throw G4HadronicException(__FILE__, __LINE__, |
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| 157 | "G4CompetitiveFission::BreakUp: Fragments Mass > Total Energy"); |
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| 158 | } |
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| 159 | // Maximal Kinetic Energy (available energy for fragments) |
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| 160 | G4double Tmax = M + U - M1 - M2; |
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[819] | 161 | |
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[1347] | 162 | FragmentsKineticEnergy = FissionKineticEnergy( A , Z, |
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| 163 | A1, Z1, |
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| 164 | A2, Z2, |
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| 165 | U , Tmax, |
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| 166 | theParameters); |
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[819] | 167 | |
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[1347] | 168 | // Excitation Energy |
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| 169 | // FragmentsExcitationEnergy = Tmax - FragmentsKineticEnergy; |
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| 170 | // JMQ 04/03/09 BUG FIXED: in order to fulfill energy conservation the |
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| 171 | // fragments carry the fission pairing energy in form of |
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| 172 | //excitation energy |
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[1055] | 173 | |
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[1347] | 174 | FragmentsExcitationEnergy = |
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| 175 | Tmax - FragmentsKineticEnergy+FissionPairingEnergy; |
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[1055] | 176 | |
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[1347] | 177 | } while (FragmentsExcitationEnergy < 0.0 && Trials++ < 100); |
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[819] | 178 | |
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[1347] | 179 | if (FragmentsExcitationEnergy <= 0.0) { |
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| 180 | throw G4HadronicException(__FILE__, __LINE__, |
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| 181 | "G4CompetitiveFission::BreakItUp: Excitation energy for fragments < 0.0!"); |
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| 182 | } |
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[819] | 183 | |
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[1347] | 184 | // while (FragmentsExcitationEnergy < 0 && Trials < 100); |
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[819] | 185 | |
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[1347] | 186 | // Fragment 1 |
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| 187 | G4double U1 = FragmentsExcitationEnergy * A1/static_cast<G4double>(A); |
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[819] | 188 | // Fragment 2 |
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[1347] | 189 | G4double U2 = FragmentsExcitationEnergy * A2/static_cast<G4double>(A); |
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[819] | 190 | |
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[1347] | 191 | //JMQ 04/03/09 Full relativistic calculation is performed |
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| 192 | // |
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| 193 | G4double Fragment1KineticEnergy= |
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| 194 | (FragmentsKineticEnergy*(FragmentsKineticEnergy+2*(M2+U2))) |
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| 195 | /(2*(M1+U1+M2+U2+FragmentsKineticEnergy)); |
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| 196 | G4ParticleMomentum Momentum1(IsotropicVector(std::sqrt(Fragment1KineticEnergy*(Fragment1KineticEnergy+2*(M1+U1))))); |
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| 197 | G4ParticleMomentum Momentum2(-Momentum1); |
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| 198 | G4LorentzVector FourMomentum1(Momentum1,std::sqrt(Momentum1.mag2()+(M1+U1)*(M1+U1))); |
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| 199 | G4LorentzVector FourMomentum2(Momentum2,std::sqrt(Momentum2.mag2()+(M2+U2)*(M2+U2))); |
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[819] | 200 | |
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[1347] | 201 | //JMQ 04/03/09 now we do Lorentz boosts (instead of Galileo boosts) |
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| 202 | FourMomentum1.boost(theNucleusMomentum.boostVector()); |
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| 203 | FourMomentum2.boost(theNucleusMomentum.boostVector()); |
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[1055] | 204 | |
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[1347] | 205 | //////////JMQ 04/03: Old version calculation is commented |
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| 206 | // There was vioation of energy momentum conservation |
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[819] | 207 | |
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[1347] | 208 | // G4double Pmax = std::sqrt( 2 * ( ( (M1+U1)*(M2+U2) ) / |
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| 209 | // ( (M1+U1)+(M2+U2) ) ) * FragmentsKineticEnergy); |
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[1055] | 210 | |
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[1347] | 211 | //G4ParticleMomentum momentum1 = IsotropicVector( Pmax ); |
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| 212 | // G4ParticleMomentum momentum2( -momentum1 ); |
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[1055] | 213 | |
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[1347] | 214 | // Perform a Galileo boost for fragments |
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| 215 | // momentum1 += (theNucleusMomentum.boostVector() * (M1+U1)); |
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| 216 | // momentum2 += (theNucleusMomentum.boostVector() * (M2+U2)); |
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[819] | 217 | |
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| 218 | |
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[1347] | 219 | // Create 4-momentum for first fragment |
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| 220 | // Warning!! Energy conservation is broken |
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| 221 | //JMQ 04/03/09 ...NOT ANY MORE!! BUGS FIXED: Energy and momentum are NOW conserved |
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| 222 | // G4LorentzVector FourMomentum1( momentum1 , std::sqrt(momentum1.mag2() + (M1+U1)*(M1+U1))); |
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[819] | 223 | |
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[1347] | 224 | // Create 4-momentum for second fragment |
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| 225 | // Warning!! Energy conservation is broken |
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| 226 | //JMQ 04/03/09 ...NOT ANY MORE!! BUGS FIXED: Energy and momentum are NOW conserved |
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| 227 | // G4LorentzVector FourMomentum2( momentum2 , std::sqrt(momentum2.mag2() + (M2+U2)*(M2+U2))); |
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[819] | 228 | |
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[1347] | 229 | ////////// |
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[1055] | 230 | |
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[1347] | 231 | // Create Fragments |
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| 232 | G4Fragment * Fragment1 = new G4Fragment( A1, Z1, FourMomentum1); |
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| 233 | G4Fragment * Fragment2 = new G4Fragment( A2, Z2, FourMomentum2); |
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[819] | 234 | |
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[1347] | 235 | // Create Fragment Vector |
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| 236 | G4FragmentVector * theResult = new G4FragmentVector; |
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[819] | 237 | |
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[1347] | 238 | theResult->push_back(Fragment1); |
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| 239 | theResult->push_back(Fragment2); |
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[819] | 240 | |
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| 241 | #ifdef debug |
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[1347] | 242 | CheckConservation(theNucleus,theResult); |
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[819] | 243 | #endif |
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| 244 | |
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[1347] | 245 | return theResult; |
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[819] | 246 | } |
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| 247 | |
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[1347] | 248 | G4int |
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| 249 | G4CompetitiveFission::FissionAtomicNumber(G4int A, |
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| 250 | const G4FissionParameters & theParam) |
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| 251 | // Calculates the atomic number of a fission product |
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[819] | 252 | { |
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| 253 | |
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[1347] | 254 | // For Simplicity reading code |
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| 255 | const G4double A1 = theParam.GetA1(); |
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| 256 | const G4double A2 = theParam.GetA2(); |
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| 257 | const G4double As = theParam.GetAs(); |
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| 258 | // const G4double Sigma1 = theParam.GetSigma1(); |
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| 259 | const G4double Sigma2 = theParam.GetSigma2(); |
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| 260 | const G4double SigmaS = theParam.GetSigmaS(); |
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| 261 | const G4double w = theParam.GetW(); |
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[819] | 262 | |
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[1347] | 263 | // G4double FasymAsym = 2.0*std::exp(-((A2-As)*(A2-As))/(2.0*Sigma2*Sigma2)) + |
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| 264 | // std::exp(-((A1-As)*(A1-As))/(2.0*Sigma1*Sigma1)); |
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[819] | 265 | |
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[1347] | 266 | // G4double FsymA1A2 = std::exp(-((As-(A1+A2))*(As-(A1+A2)))/(2.0*SigmaS*SigmaS)); |
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[819] | 267 | |
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[1347] | 268 | G4double C2A = A2 + 3.72*Sigma2; |
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| 269 | G4double C2S = As + 3.72*SigmaS; |
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[819] | 270 | |
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[1347] | 271 | G4double C2 = 0.0; |
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| 272 | if (w > 1000.0 ) C2 = C2S; |
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| 273 | else if (w < 0.001) C2 = C2A; |
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| 274 | else C2 = std::max(C2A,C2S); |
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[819] | 275 | |
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[1347] | 276 | G4double C1 = A-C2; |
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| 277 | if (C1 < 30.0) { |
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| 278 | C2 = A-30.0; |
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| 279 | C1 = 30.0; |
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| 280 | } |
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[819] | 281 | |
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[1347] | 282 | G4double Am1 = (As + A1)/2.0; |
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| 283 | G4double Am2 = (A1 + A2)/2.0; |
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[819] | 284 | |
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[1347] | 285 | // Get Mass distributions as sum of symmetric and asymmetric Gasussians |
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| 286 | G4double Mass1 = MassDistribution(As,A,theParam); |
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| 287 | G4double Mass2 = MassDistribution(Am1,A,theParam); |
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| 288 | G4double Mass3 = MassDistribution(A1,A,theParam); |
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| 289 | G4double Mass4 = MassDistribution(Am2,A,theParam); |
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| 290 | G4double Mass5 = MassDistribution(A2,A,theParam); |
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| 291 | // get maximal value among Mass1,...,Mass5 |
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| 292 | G4double MassMax = Mass1; |
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| 293 | if (Mass2 > MassMax) MassMax = Mass2; |
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| 294 | if (Mass3 > MassMax) MassMax = Mass3; |
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| 295 | if (Mass4 > MassMax) MassMax = Mass4; |
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| 296 | if (Mass5 > MassMax) MassMax = Mass5; |
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[819] | 297 | |
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[1347] | 298 | // Sample a fragment mass number, which lies between C1 and C2 |
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| 299 | G4double m; |
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| 300 | G4double Pm; |
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| 301 | do { |
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| 302 | m = C1+G4UniformRand()*(C2-C1); |
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| 303 | Pm = MassDistribution(m,A,theParam); |
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| 304 | } while (MassMax*G4UniformRand() > Pm); |
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[819] | 305 | |
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[1347] | 306 | return static_cast<G4int>(m+0.5); |
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[819] | 307 | } |
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| 308 | |
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[1347] | 309 | G4double |
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| 310 | G4CompetitiveFission::MassDistribution(G4double x, G4double A, |
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| 311 | const G4FissionParameters & theParam) |
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| 312 | // This method gives mass distribution F(x) = F_{asym}(x)+w*F_{sym}(x) |
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| 313 | // which consist of symmetric and asymmetric sum of gaussians components. |
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[819] | 314 | { |
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[1347] | 315 | G4double Xsym = std::exp(-0.5*(x-theParam.GetAs())*(x-theParam.GetAs())/ |
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| 316 | (theParam.GetSigmaS()*theParam.GetSigmaS())); |
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[819] | 317 | |
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[1347] | 318 | G4double Xasym = std::exp(-0.5*(x-theParam.GetA2())*(x-theParam.GetA2())/ |
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| 319 | (theParam.GetSigma2()*theParam.GetSigma2())) + |
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| 320 | std::exp(-0.5*(x-(A-theParam.GetA2()))*(x-(A-theParam.GetA2()))/ |
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| 321 | (theParam.GetSigma2()*theParam.GetSigma2())) + |
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| 322 | 0.5*std::exp(-0.5*(x-theParam.GetA1())*(x-theParam.GetA1())/ |
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| 323 | (theParam.GetSigma1()*theParam.GetSigma1())) + |
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| 324 | 0.5*std::exp(-0.5*(x-(A-theParam.GetA1()))*(x-(A-theParam.GetA1()))/ |
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| 325 | (theParam.GetSigma1()*theParam.GetSigma1())); |
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[819] | 326 | |
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[1347] | 327 | if (theParam.GetW() > 1000) return Xsym; |
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| 328 | else if (theParam.GetW() < 0.001) return Xasym; |
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| 329 | else return theParam.GetW()*Xsym+Xasym; |
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[819] | 330 | } |
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| 331 | |
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[1347] | 332 | G4int G4CompetitiveFission::FissionCharge(G4double A, G4double Z, |
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| 333 | G4double Af) |
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| 334 | // Calculates the charge of a fission product for a given atomic number Af |
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[819] | 335 | { |
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[1347] | 336 | const G4double sigma = 0.6; |
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| 337 | G4double DeltaZ = 0.0; |
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| 338 | if (Af >= 134.0) DeltaZ = -0.45; // 134 <= Af |
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| 339 | else if (Af <= (A-134.0)) DeltaZ = 0.45; // Af <= (A-134) |
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| 340 | else DeltaZ = -0.45*(Af-(A/2.0))/(134.0-(A/2.0)); // (A-134) < Af < 134 |
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[819] | 341 | |
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[1347] | 342 | G4double Zmean = (Af/A)*Z + DeltaZ; |
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[819] | 343 | |
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[1347] | 344 | G4double theZ; |
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| 345 | do { |
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| 346 | theZ = G4RandGauss::shoot(Zmean,sigma); |
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| 347 | } while (theZ < 1.0 || theZ > (Z-1.0) || theZ > Af); |
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| 348 | // return static_cast<G4int>(theZ+0.5); |
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| 349 | return static_cast<G4int>(theZ+0.5); |
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[819] | 350 | } |
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| 351 | |
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[1347] | 352 | G4double |
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| 353 | G4CompetitiveFission::FissionKineticEnergy(G4int A, G4int Z, |
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| 354 | G4double Af1, G4double /*Zf1*/, |
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| 355 | G4double Af2, G4double /*Zf2*/, |
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| 356 | G4double /*U*/, G4double Tmax, |
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| 357 | const G4FissionParameters & theParam) |
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| 358 | // Gives the kinetic energy of fission products |
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[819] | 359 | { |
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[1347] | 360 | // Find maximal value of A for fragments |
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| 361 | G4double AfMax = std::max(Af1,Af2); |
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| 362 | if (AfMax < (A/2.0)) AfMax = A - AfMax; |
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[819] | 363 | |
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[1347] | 364 | // Weights for symmetric and asymmetric components |
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| 365 | G4double Pas; |
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| 366 | if (theParam.GetW() > 1000) Pas = 0.0; |
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| 367 | else { |
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| 368 | G4double P1 = 0.5*std::exp(-0.5*(AfMax-theParam.GetA1())*(AfMax-theParam.GetA1())/ |
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| 369 | (theParam.GetSigma1()*theParam.GetSigma1())); |
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[819] | 370 | |
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[1347] | 371 | G4double P2 = std::exp(-0.5*(AfMax-theParam.GetA2())*(AfMax-theParam.GetA2())/ |
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| 372 | (theParam.GetSigma2()*theParam.GetSigma2())); |
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[819] | 373 | |
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[1347] | 374 | Pas = P1+P2; |
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| 375 | } |
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[819] | 376 | |
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[1347] | 377 | G4double Ps; |
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| 378 | if (theParam.GetW() < 0.001) Ps = 0.0; |
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| 379 | else { |
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| 380 | Ps = theParam.GetW()*std::exp(-0.5*(AfMax-theParam.GetAs())*(AfMax-theParam.GetAs())/ |
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| 381 | (theParam.GetSigmaS()*theParam.GetSigmaS())); |
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| 382 | } |
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| 383 | G4double Psy = Ps/(Pas+Ps); |
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[819] | 384 | |
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[1347] | 385 | // Fission fractions Xsy and Xas formed in symmetric and asymmetric modes |
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| 386 | G4double PPas = theParam.GetSigma1() + 2.0 * theParam.GetSigma2(); |
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| 387 | G4double PPsy = theParam.GetW() * theParam.GetSigmaS(); |
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| 388 | G4double Xas = PPas / (PPas+PPsy); |
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| 389 | G4double Xsy = PPsy / (PPas+PPsy); |
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[819] | 390 | |
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[1347] | 391 | // Average kinetic energy for symmetric and asymmetric components |
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| 392 | G4double Eaverage = 0.1071*MeV*(Z*Z)/G4Pow::GetInstance()->Z13(A) + 22.2*MeV; |
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[819] | 393 | |
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| 394 | |
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[1347] | 395 | // Compute maximal average kinetic energy of fragments and Energy Dispersion (sqrt) |
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| 396 | G4double TaverageAfMax; |
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| 397 | G4double ESigma; |
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| 398 | // Select randomly fission mode (symmetric or asymmetric) |
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| 399 | if (G4UniformRand() > Psy) { // Asymmetric Mode |
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| 400 | G4double A11 = theParam.GetA1()-0.7979*theParam.GetSigma1(); |
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| 401 | G4double A12 = theParam.GetA1()+0.7979*theParam.GetSigma1(); |
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| 402 | G4double A21 = theParam.GetA2()-0.7979*theParam.GetSigma2(); |
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| 403 | G4double A22 = theParam.GetA2()+0.7979*theParam.GetSigma2(); |
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| 404 | // scale factor |
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| 405 | G4double ScaleFactor = 0.5*theParam.GetSigma1()*(AsymmetricRatio(A,A11)+AsymmetricRatio(A,A12))+ |
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| 406 | theParam.GetSigma2()*(AsymmetricRatio(A,A21)+AsymmetricRatio(A,A22)); |
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| 407 | // Compute average kinetic energy for fragment with AfMax |
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| 408 | TaverageAfMax = (Eaverage + 12.5 * Xsy) * (PPas/ScaleFactor) * AsymmetricRatio(A,AfMax); |
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| 409 | ESigma = 10.0*MeV; // MeV |
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[819] | 410 | |
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[1347] | 411 | } else { // Symmetric Mode |
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| 412 | G4double As0 = theParam.GetAs() + 0.7979*theParam.GetSigmaS(); |
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| 413 | // scale factor |
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| 414 | G4double ScaleFactor = theParam.GetW()*theParam.GetSigmaS()*SymmetricRatio(A,As0); |
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| 415 | // Compute average kinetic energy for fragment with AfMax |
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| 416 | TaverageAfMax = (Eaverage - 12.5*MeV*Xas) * (PPsy/ScaleFactor) * SymmetricRatio(A,AfMax); |
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| 417 | ESigma = 8.0*MeV; |
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| 418 | } |
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[819] | 419 | |
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| 420 | |
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[1347] | 421 | // Select randomly, in accordance with Gaussian distribution, fragment kinetic energy |
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| 422 | G4double KineticEnergy; |
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| 423 | G4int i = 0; |
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| 424 | do { |
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| 425 | KineticEnergy = G4RandGauss::shoot(TaverageAfMax,ESigma); |
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| 426 | if (i++ > 100) return Eaverage; |
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| 427 | } while (KineticEnergy < Eaverage-3.72*ESigma || |
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| 428 | KineticEnergy > Eaverage+3.72*ESigma || |
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| 429 | KineticEnergy > Tmax); |
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| 430 | |
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| 431 | return KineticEnergy; |
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[819] | 432 | } |
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| 433 | |
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[1347] | 434 | G4double G4CompetitiveFission::AsymmetricRatio(G4int A, G4double A11) |
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[819] | 435 | { |
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[1347] | 436 | const G4double B1 = 23.5; |
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| 437 | const G4double A00 = 134.0; |
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| 438 | return Ratio(G4double(A),A11,B1,A00); |
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[819] | 439 | } |
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| 440 | |
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[1347] | 441 | G4double G4CompetitiveFission::SymmetricRatio(G4int A, G4double A11) |
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[819] | 442 | { |
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[1347] | 443 | const G4double B1 = 5.32; |
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| 444 | const G4double A00 = A/2.0; |
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| 445 | return Ratio(G4double(A),A11,B1,A00); |
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[819] | 446 | } |
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| 447 | |
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[1347] | 448 | G4double G4CompetitiveFission::Ratio(G4double A, G4double A11, |
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| 449 | G4double B1, G4double A00) |
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[819] | 450 | { |
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[1347] | 451 | if (A == 0.0) { |
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| 452 | throw G4HadronicException(__FILE__, __LINE__, |
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| 453 | "G4CompetitiveFission::Ratio: A == 0!"); |
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| 454 | } |
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| 455 | if (A11 >= A/2.0 && A11 <= (A00+10.0)) { |
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| 456 | return 1.0-B1*((A11-A00)/A)*((A11-A00)/A); |
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| 457 | } else { |
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| 458 | return 1.0-B1*(10.0/A)*(10.0/A)-2.0*(10.0/A)*B1*((A11-A00-10.0)/A); |
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| 459 | } |
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[819] | 460 | } |
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| 461 | |
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| 462 | G4ThreeVector G4CompetitiveFission::IsotropicVector(const G4double Magnitude) |
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[1347] | 463 | // Samples a isotropic random vectorwith a magnitud given by Magnitude. |
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| 464 | // By default Magnitude = 1.0 |
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[819] | 465 | { |
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[1347] | 466 | G4double CosTheta = 1.0 - 2.0*G4UniformRand(); |
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| 467 | G4double SinTheta = std::sqrt(1.0 - CosTheta*CosTheta); |
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| 468 | G4double Phi = twopi*G4UniformRand(); |
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| 469 | G4ThreeVector Vector(Magnitude*std::cos(Phi)*SinTheta, |
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| 470 | Magnitude*std::sin(Phi)*SinTheta, |
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| 471 | Magnitude*CosTheta); |
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| 472 | return Vector; |
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[819] | 473 | } |
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| 474 | |
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| 475 | #ifdef debug |
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| 476 | void G4CompetitiveFission::CheckConservation(const G4Fragment & theInitialState, |
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| 477 | G4FragmentVector * Result) const |
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| 478 | { |
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| 479 | G4double ProductsEnergy =0; |
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| 480 | G4ThreeVector ProductsMomentum; |
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| 481 | G4int ProductsA = 0; |
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| 482 | G4int ProductsZ = 0; |
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| 483 | G4FragmentVector::iterator h; |
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| 484 | for (h = Result->begin(); h != Result->end(); h++) { |
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| 485 | G4LorentzVector tmp = (*h)->GetMomentum(); |
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| 486 | ProductsEnergy += tmp.e(); |
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| 487 | ProductsMomentum += tmp.vect(); |
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| 488 | ProductsA += static_cast<G4int>((*h)->GetA()); |
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| 489 | ProductsZ += static_cast<G4int>((*h)->GetZ()); |
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| 490 | } |
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| 491 | |
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| 492 | if (ProductsA != theInitialState.GetA()) { |
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| 493 | G4cout << "!!!!!!!!!! Baryonic Number Conservation Violation !!!!!!!!!!" << G4endl; |
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| 494 | G4cout << "G4CompetitiveFission.cc: Barionic Number Conservation test for fission fragments" |
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| 495 | << G4endl; |
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| 496 | G4cout << "Initial A = " << theInitialState.GetA() |
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| 497 | << " Fragments A = " << ProductsA << " Diference --> " |
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| 498 | << theInitialState.GetA() - ProductsA << G4endl; |
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| 499 | } |
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| 500 | if (ProductsZ != theInitialState.GetZ()) { |
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| 501 | G4cout << "!!!!!!!!!! Charge Conservation Violation !!!!!!!!!!" << G4endl; |
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| 502 | G4cout << "G4CompetitiveFission.cc: Charge Conservation test for fission fragments" |
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| 503 | << G4endl; |
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| 504 | G4cout << "Initial Z = " << theInitialState.GetZ() |
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| 505 | << " Fragments Z = " << ProductsZ << " Diference --> " |
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| 506 | << theInitialState.GetZ() - ProductsZ << G4endl; |
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| 507 | } |
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| 508 | if (std::abs(ProductsEnergy-theInitialState.GetMomentum().e()) > 1.0*keV) { |
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| 509 | G4cout << "!!!!!!!!!! Energy Conservation Violation !!!!!!!!!!" << G4endl; |
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| 510 | G4cout << "G4CompetitiveFission.cc: Energy Conservation test for fission fragments" |
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| 511 | << G4endl; |
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| 512 | G4cout << "Initial E = " << theInitialState.GetMomentum().e()/MeV << " MeV" |
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| 513 | << " Fragments E = " << ProductsEnergy/MeV << " MeV Diference --> " |
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| 514 | << (theInitialState.GetMomentum().e() - ProductsEnergy)/MeV << " MeV" << G4endl; |
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| 515 | } |
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| 516 | if (std::abs(ProductsMomentum.x()-theInitialState.GetMomentum().x()) > 1.0*keV || |
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| 517 | std::abs(ProductsMomentum.y()-theInitialState.GetMomentum().y()) > 1.0*keV || |
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| 518 | std::abs(ProductsMomentum.z()-theInitialState.GetMomentum().z()) > 1.0*keV) { |
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| 519 | G4cout << "!!!!!!!!!! Momentum Conservation Violation !!!!!!!!!!" << G4endl; |
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| 520 | G4cout << "G4CompetitiveFission.cc: Momentum Conservation test for fission fragments" |
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| 521 | << G4endl; |
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| 522 | G4cout << "Initial P = " << theInitialState.GetMomentum().vect() << " MeV" |
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| 523 | << " Fragments P = " << ProductsMomentum << " MeV Diference --> " |
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| 524 | << theInitialState.GetMomentum().vect() - ProductsMomentum << " MeV" << G4endl; |
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| 525 | } |
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| 526 | return; |
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| 527 | } |
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| 528 | #endif |
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| 529 | |
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| 530 | |
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| 531 | |
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| 532 | |
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