[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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[961] | 26 | // $Id: G4eplusPolarizedAnnihilation.cc,v 1.8 2008/10/30 22:34:23 schaelic 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 | // |
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| 31 | // GEANT4 Class file |
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| 32 | // |
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| 33 | // |
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| 34 | // File name: G4eplusPolarizedAnnihilation |
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| 35 | // |
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| 36 | // Author: A. Schaelicke on base of Vladimir Ivanchenko / Michel Maire code |
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| 37 | // |
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| 38 | // Creation date: 02.07.2006 |
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| 39 | // |
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| 40 | // Modifications: |
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| 41 | // 26-07-06 modified cross section (P. Starovoitov) |
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| 42 | // 21-08-06 interface updated (A. Schaelicke) |
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| 43 | // 11-06-07, add PostStepGetPhysicalInteractionLength (A.Schalicke) |
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| 44 | // 02-10-07, enable AtRest (V.Ivanchenko) |
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| 45 | // |
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| 46 | // |
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| 47 | // Class Description: |
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| 48 | // |
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| 49 | // Polarized process of e+ annihilation into 2 gammas |
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| 50 | // |
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| 51 | |
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| 52 | // |
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| 53 | // ------------------------------------------------------------------- |
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| 54 | // |
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| 55 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 56 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 57 | |
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| 58 | #include "G4eplusPolarizedAnnihilation.hh" |
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| 59 | #include "G4MaterialCutsCouple.hh" |
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| 60 | #include "G4Gamma.hh" |
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| 61 | #include "G4PhysicsVector.hh" |
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| 62 | #include "G4PhysicsLogVector.hh" |
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| 63 | |
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| 64 | |
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| 65 | #include "G4PolarizedAnnihilationModel.hh" |
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| 66 | #include "G4PhysicsTableHelper.hh" |
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| 67 | #include "G4ProductionCutsTable.hh" |
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| 68 | #include "G4PolarizationManager.hh" |
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| 69 | #include "G4PolarizationHelper.hh" |
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| 70 | #include "G4StokesVector.hh" |
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| 71 | |
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| 72 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 73 | |
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| 74 | G4eplusPolarizedAnnihilation::G4eplusPolarizedAnnihilation(const G4String& name) |
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| 75 | : G4VEmProcess(name), isInitialised(false), |
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| 76 | theAsymmetryTable(NULL), |
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| 77 | theTransverseAsymmetryTable(NULL) |
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| 78 | { |
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| 79 | enableAtRestDoIt = true; |
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[961] | 80 | SetProcessSubType(fAnnihilation); |
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[819] | 81 | } |
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| 82 | |
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| 83 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 84 | |
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| 85 | G4eplusPolarizedAnnihilation::~G4eplusPolarizedAnnihilation() |
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| 86 | { |
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| 87 | if (theAsymmetryTable) { |
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| 88 | theAsymmetryTable->clearAndDestroy(); |
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| 89 | delete theAsymmetryTable; |
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| 90 | } |
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| 91 | if (theTransverseAsymmetryTable) { |
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| 92 | theTransverseAsymmetryTable->clearAndDestroy(); |
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| 93 | delete theTransverseAsymmetryTable; |
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| 94 | } |
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| 95 | } |
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| 96 | |
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| 97 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 98 | |
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| 99 | void G4eplusPolarizedAnnihilation::InitialiseProcess(const G4ParticleDefinition*) |
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| 100 | { |
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| 101 | if(!isInitialised) { |
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| 102 | isInitialised = true; |
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| 103 | // SetVerboseLevel(3); |
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| 104 | SetBuildTableFlag(true); |
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| 105 | SetStartFromNullFlag(false); |
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| 106 | SetSecondaryParticle(G4Gamma::Gamma()); |
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| 107 | G4double emin = 0.1*keV; |
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| 108 | G4double emax = 100.*TeV; |
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| 109 | SetLambdaBinning(120); |
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| 110 | SetMinKinEnergy(emin); |
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| 111 | SetMaxKinEnergy(emax); |
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| 112 | emModel = new G4PolarizedAnnihilationModel(); |
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| 113 | emModel->SetLowEnergyLimit(emin); |
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| 114 | emModel->SetHighEnergyLimit(emax); |
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| 115 | AddEmModel(1, emModel); |
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| 116 | } |
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| 117 | } |
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| 118 | |
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| 119 | |
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| 120 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 121 | |
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| 122 | // for polarization |
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| 123 | |
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| 124 | G4double G4eplusPolarizedAnnihilation::GetMeanFreePath(const G4Track& track, |
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| 125 | G4double previousStepSize, |
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| 126 | G4ForceCondition* condition) |
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| 127 | { |
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| 128 | G4double mfp = G4VEmProcess::GetMeanFreePath(track, previousStepSize, condition); |
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| 129 | |
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| 130 | if (theAsymmetryTable) { |
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| 131 | |
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| 132 | G4Material* aMaterial = track.GetMaterial(); |
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| 133 | G4VPhysicalVolume* aPVolume = track.GetVolume(); |
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| 134 | G4LogicalVolume* aLVolume = aPVolume->GetLogicalVolume(); |
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| 135 | |
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| 136 | // G4Material* bMaterial = aLVolume->GetMaterial(); |
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| 137 | G4PolarizationManager * polarizationManger = G4PolarizationManager::GetInstance(); |
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| 138 | |
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| 139 | const G4bool volumeIsPolarized = polarizationManger->IsPolarized(aLVolume); |
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| 140 | G4StokesVector electronPolarization = polarizationManger->GetVolumePolarization(aLVolume); |
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| 141 | |
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| 142 | if (!volumeIsPolarized || mfp == DBL_MAX) return mfp; |
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| 143 | |
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| 144 | // *** get asymmetry, if target is polarized *** |
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| 145 | const G4DynamicParticle* aDynamicPositron = track.GetDynamicParticle(); |
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| 146 | const G4double positronEnergy = aDynamicPositron->GetKineticEnergy(); |
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| 147 | const G4StokesVector positronPolarization = track.GetPolarization(); |
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| 148 | const G4ParticleMomentum positronDirection0 = aDynamicPositron->GetMomentumDirection(); |
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| 149 | |
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| 150 | if (verboseLevel>=2) { |
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| 151 | |
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| 152 | G4cout << " Mom " << positronDirection0 << G4endl; |
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| 153 | G4cout << " Polarization " << positronPolarization << G4endl; |
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| 154 | G4cout << " MaterialPol. " << electronPolarization << G4endl; |
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| 155 | G4cout << " Phys. Volume " << aPVolume->GetName() << G4endl; |
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| 156 | G4cout << " Log. Volume " << aLVolume->GetName() << G4endl; |
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| 157 | G4cout << " Material " << aMaterial << G4endl; |
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| 158 | } |
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| 159 | |
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| 160 | G4bool isOutRange; |
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| 161 | G4int idx= CurrentMaterialCutsCoupleIndex(); |
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| 162 | G4double lAsymmetry = (*theAsymmetryTable)(idx)-> |
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| 163 | GetValue(positronEnergy, isOutRange); |
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| 164 | G4double tAsymmetry = (*theTransverseAsymmetryTable)(idx)-> |
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| 165 | GetValue(positronEnergy, isOutRange); |
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| 166 | |
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| 167 | G4double polZZ = positronPolarization.z()* |
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| 168 | electronPolarization*positronDirection0; |
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| 169 | G4double polXX = positronPolarization.x()* |
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| 170 | electronPolarization*G4PolarizationHelper::GetParticleFrameX(positronDirection0); |
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| 171 | G4double polYY = positronPolarization.y()* |
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| 172 | electronPolarization*G4PolarizationHelper::GetParticleFrameY(positronDirection0); |
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| 173 | |
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| 174 | G4double impact = 1. + polZZ*lAsymmetry + (polXX + polYY)*tAsymmetry; |
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| 175 | |
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| 176 | mfp *= 1. / impact; |
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| 177 | |
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| 178 | if (verboseLevel>=2) { |
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| 179 | G4cout << " MeanFreePath: " << mfp / mm << " mm " << G4endl; |
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| 180 | G4cout << " Asymmetry: " << lAsymmetry << ", " << tAsymmetry << G4endl; |
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| 181 | G4cout << " PolProduct: " << polXX << ", " << polYY << ", " << polZZ << G4endl; |
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| 182 | } |
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| 183 | } |
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| 184 | |
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| 185 | return mfp; |
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| 186 | } |
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| 187 | |
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| 188 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 189 | |
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| 190 | G4double G4eplusPolarizedAnnihilation::PostStepGetPhysicalInteractionLength( |
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| 191 | const G4Track& track, |
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| 192 | G4double previousStepSize, |
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| 193 | G4ForceCondition* condition) |
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| 194 | { |
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| 195 | G4double mfp = G4VEmProcess::PostStepGetPhysicalInteractionLength(track, previousStepSize, condition); |
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| 196 | |
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| 197 | if (theAsymmetryTable) { |
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| 198 | |
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| 199 | G4Material* aMaterial = track.GetMaterial(); |
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| 200 | G4VPhysicalVolume* aPVolume = track.GetVolume(); |
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| 201 | G4LogicalVolume* aLVolume = aPVolume->GetLogicalVolume(); |
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| 202 | |
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| 203 | // G4Material* bMaterial = aLVolume->GetMaterial(); |
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| 204 | G4PolarizationManager * polarizationManger = G4PolarizationManager::GetInstance(); |
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| 205 | |
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| 206 | const G4bool volumeIsPolarized = polarizationManger->IsPolarized(aLVolume); |
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| 207 | G4StokesVector electronPolarization = polarizationManger->GetVolumePolarization(aLVolume); |
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| 208 | |
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| 209 | if (!volumeIsPolarized || mfp == DBL_MAX) return mfp; |
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| 210 | |
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| 211 | // *** get asymmetry, if target is polarized *** |
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| 212 | const G4DynamicParticle* aDynamicPositron = track.GetDynamicParticle(); |
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| 213 | const G4double positronEnergy = aDynamicPositron->GetKineticEnergy(); |
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| 214 | const G4StokesVector positronPolarization = track.GetPolarization(); |
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| 215 | const G4ParticleMomentum positronDirection0 = aDynamicPositron->GetMomentumDirection(); |
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| 216 | |
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| 217 | if (verboseLevel>=2) { |
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| 218 | |
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| 219 | G4cout << " Mom " << positronDirection0 << G4endl; |
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| 220 | G4cout << " Polarization " << positronPolarization << G4endl; |
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| 221 | G4cout << " MaterialPol. " << electronPolarization << G4endl; |
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| 222 | G4cout << " Phys. Volume " << aPVolume->GetName() << G4endl; |
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| 223 | G4cout << " Log. Volume " << aLVolume->GetName() << G4endl; |
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| 224 | G4cout << " Material " << aMaterial << G4endl; |
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| 225 | } |
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| 226 | |
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| 227 | G4bool isOutRange; |
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| 228 | G4int idx= CurrentMaterialCutsCoupleIndex(); |
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| 229 | G4double lAsymmetry = (*theAsymmetryTable)(idx)-> |
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| 230 | GetValue(positronEnergy, isOutRange); |
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| 231 | G4double tAsymmetry = (*theTransverseAsymmetryTable)(idx)-> |
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| 232 | GetValue(positronEnergy, isOutRange); |
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| 233 | |
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| 234 | G4double polZZ = positronPolarization.z()* |
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| 235 | electronPolarization*positronDirection0; |
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| 236 | G4double polXX = positronPolarization.x()* |
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| 237 | electronPolarization*G4PolarizationHelper::GetParticleFrameX(positronDirection0); |
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| 238 | G4double polYY = positronPolarization.y()* |
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| 239 | electronPolarization*G4PolarizationHelper::GetParticleFrameY(positronDirection0); |
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| 240 | |
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| 241 | G4double impact = 1. + polZZ*lAsymmetry + (polXX + polYY)*tAsymmetry; |
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| 242 | |
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| 243 | mfp *= 1. / impact; |
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| 244 | |
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| 245 | if (verboseLevel>=2) { |
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| 246 | G4cout << " MeanFreePath: " << mfp / mm << " mm " << G4endl; |
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| 247 | G4cout << " Asymmetry: " << lAsymmetry << ", " << tAsymmetry << G4endl; |
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| 248 | G4cout << " PolProduct: " << polXX << ", " << polYY << ", " << polZZ << G4endl; |
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| 249 | } |
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| 250 | } |
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| 251 | |
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| 252 | return mfp; |
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| 253 | } |
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| 254 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 255 | |
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| 256 | void G4eplusPolarizedAnnihilation::BuildPhysicsTable(const G4ParticleDefinition& pd) |
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| 257 | { |
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| 258 | G4VEmProcess::BuildPhysicsTable(pd); |
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| 259 | BuildAsymmetryTable(pd); |
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| 260 | } |
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| 261 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 262 | |
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| 263 | void G4eplusPolarizedAnnihilation::PreparePhysicsTable(const G4ParticleDefinition& pd) |
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| 264 | { |
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| 265 | G4VEmProcess::PreparePhysicsTable(pd); |
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| 266 | theAsymmetryTable = G4PhysicsTableHelper::PreparePhysicsTable(theAsymmetryTable); |
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| 267 | theTransverseAsymmetryTable = G4PhysicsTableHelper::PreparePhysicsTable(theTransverseAsymmetryTable); |
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| 268 | } |
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| 269 | |
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| 270 | void G4eplusPolarizedAnnihilation::BuildAsymmetryTable(const G4ParticleDefinition& part) |
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| 271 | { |
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| 272 | // Access to materials |
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| 273 | const G4ProductionCutsTable* theCoupleTable= |
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| 274 | G4ProductionCutsTable::GetProductionCutsTable(); |
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| 275 | size_t numOfCouples = theCoupleTable->GetTableSize(); |
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| 276 | G4cout<<" annih-numOfCouples="<<numOfCouples<<"\n"; |
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| 277 | for(size_t i=0; i<numOfCouples; ++i) { |
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| 278 | G4cout<<"annih- "<<i<<"/"<<numOfCouples<<"\n"; |
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| 279 | if (!theAsymmetryTable) break; |
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| 280 | G4cout<<"annih- "<<theAsymmetryTable->GetFlag(i)<<"\n"; |
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| 281 | if (theAsymmetryTable->GetFlag(i)) { |
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| 282 | G4cout<<" building pol-annih ... \n"; |
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| 283 | |
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| 284 | // create physics vector and fill it |
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| 285 | const G4MaterialCutsCouple* couple = theCoupleTable->GetMaterialCutsCouple(i); |
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| 286 | |
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| 287 | // use same parameters as for lambda |
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| 288 | G4PhysicsVector* aVector = LambdaPhysicsVector(couple); |
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| 289 | G4PhysicsVector* tVector = LambdaPhysicsVector(couple); |
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| 290 | |
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| 291 | for (G4int j = 0 ; j < LambdaBinning() ; ++j ) { |
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| 292 | G4double lowEdgeEnergy = aVector->GetLowEdgeEnergy(j); |
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| 293 | G4double tasm=0.; |
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| 294 | G4double asym = ComputeAsymmetry(lowEdgeEnergy, couple, part, 0., tasm); |
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| 295 | aVector->PutValue(j,asym); |
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| 296 | tVector->PutValue(j,tasm); |
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| 297 | } |
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| 298 | |
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| 299 | G4PhysicsTableHelper::SetPhysicsVector(theAsymmetryTable, i, aVector); |
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| 300 | G4PhysicsTableHelper::SetPhysicsVector(theTransverseAsymmetryTable, i, tVector); |
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| 301 | } |
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| 302 | } |
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| 303 | |
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| 304 | } |
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| 305 | |
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| 306 | |
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| 307 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 308 | |
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| 309 | G4double G4eplusPolarizedAnnihilation::ComputeAsymmetry(G4double energy, |
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| 310 | const G4MaterialCutsCouple* couple, |
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| 311 | const G4ParticleDefinition& aParticle, |
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| 312 | G4double cut, |
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| 313 | G4double &tAsymmetry) |
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| 314 | { |
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| 315 | G4double lAsymmetry = 0.0; |
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| 316 | tAsymmetry = 0.0; |
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| 317 | |
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| 318 | // calculate polarized cross section |
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| 319 | theTargetPolarization=G4ThreeVector(0.,0.,1.); |
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| 320 | emModel->SetTargetPolarization(theTargetPolarization); |
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| 321 | emModel->SetBeamPolarization(theTargetPolarization); |
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| 322 | G4double sigma2=emModel->CrossSection(couple,&aParticle,energy,cut,energy); |
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| 323 | |
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| 324 | // calculate transversely polarized cross section |
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| 325 | theTargetPolarization=G4ThreeVector(1.,0.,0.); |
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| 326 | emModel->SetTargetPolarization(theTargetPolarization); |
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| 327 | emModel->SetBeamPolarization(theTargetPolarization); |
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| 328 | G4double sigma3=emModel->CrossSection(couple,&aParticle,energy,cut,energy); |
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| 329 | |
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| 330 | // calculate unpolarized cross section |
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| 331 | theTargetPolarization=G4ThreeVector(); |
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| 332 | emModel->SetTargetPolarization(theTargetPolarization); |
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| 333 | emModel->SetBeamPolarization(theTargetPolarization); |
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| 334 | G4double sigma0=emModel->CrossSection(couple,&aParticle,energy,cut,energy); |
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| 335 | |
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| 336 | // determine assymmetries |
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| 337 | if (sigma0>0.) { |
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| 338 | lAsymmetry=sigma2/sigma0-1.; |
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| 339 | tAsymmetry=sigma3/sigma0-1.; |
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| 340 | } |
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| 341 | return lAsymmetry; |
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| 342 | |
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| 343 | } |
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| 344 | |
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| 345 | |
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| 346 | |
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| 347 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 348 | |
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| 349 | void G4eplusPolarizedAnnihilation::PrintInfo() |
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| 350 | { |
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| 351 | G4cout << " Polarized model for annihilation into 2 photons" |
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| 352 | << G4endl; |
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| 353 | } |
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| 354 | |
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| 355 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 356 | |
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| 357 | G4VParticleChange* G4eplusPolarizedAnnihilation::AtRestDoIt(const G4Track& aTrack, |
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| 358 | const G4Step& ) |
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| 359 | // |
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| 360 | // Performs the e+ e- annihilation when both particles are assumed at rest. |
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| 361 | // It generates two back to back photons with energy = electron_mass. |
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| 362 | // The angular distribution is isotropic. |
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| 363 | // GEANT4 internal units |
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| 364 | // |
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| 365 | // Note : Effects due to binding of atomic electrons are negliged. |
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| 366 | { |
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| 367 | fParticleChange.InitializeForPostStep(aTrack); |
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| 368 | |
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| 369 | fParticleChange.SetNumberOfSecondaries(2); |
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| 370 | |
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| 371 | G4double cosTeta = 2.*G4UniformRand()-1. , sinTeta = std::sqrt(1.-cosTeta*cosTeta); |
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| 372 | G4double phi = twopi * G4UniformRand(); |
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| 373 | G4ThreeVector direction (sinTeta*std::cos(phi), sinTeta*std::sin(phi), cosTeta); |
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| 374 | fParticleChange.AddSecondary( new G4DynamicParticle (G4Gamma::Gamma(), |
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| 375 | direction, electron_mass_c2) ); |
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| 376 | fParticleChange.AddSecondary( new G4DynamicParticle (G4Gamma::Gamma(), |
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| 377 | -direction, electron_mass_c2) ); |
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| 378 | // Kill the incident positron |
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| 379 | // |
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| 380 | fParticleChange.ProposeTrackStatus(fStopAndKill); |
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| 381 | return &fParticleChange; |
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| 382 | } |
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| 383 | |
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| 384 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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