[968] | 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: G4DNAChampionElasticModel.cc,v 1.3 2009/02/16 11:00:11 sincerti Exp $ |
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| 27 | // GEANT4 tag $Name: geant4-09-02-ref-02 $ |
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| 28 | // |
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| 29 | |
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| 30 | #include "G4DNAChampionElasticModel.hh" |
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| 31 | |
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| 32 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 33 | |
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| 34 | using namespace std; |
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| 35 | |
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| 36 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 37 | |
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| 38 | G4DNAChampionElasticModel::G4DNAChampionElasticModel(const G4ParticleDefinition*, |
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| 39 | const G4String& nam) |
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| 40 | :G4VEmModel(nam),isInitialised(false) |
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| 41 | { |
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| 42 | |
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| 43 | killBelowEnergy = 8.23*eV; // Minimum e- energy for energy loss by excitation |
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| 44 | lowEnergyLimit = 0 * eV; |
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| 45 | lowEnergyLimitOfModel = 7 * eV; // The model lower energy is 7 eV |
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| 46 | highEnergyLimit = 10 * keV; |
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| 47 | SetLowEnergyLimit(lowEnergyLimit); |
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| 48 | SetHighEnergyLimit(highEnergyLimit); |
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| 49 | |
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| 50 | verboseLevel= 0; |
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| 51 | // Verbosity scale: |
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| 52 | // 0 = nothing |
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| 53 | // 1 = warning for energy non-conservation |
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| 54 | // 2 = details of energy budget |
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| 55 | // 3 = calculation of cross sections, file openings, sampling of atoms |
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| 56 | // 4 = entering in methods |
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| 57 | |
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| 58 | G4cout << "Champion Elastic model is constructed " << G4endl |
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| 59 | << "Energy range: " |
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| 60 | << lowEnergyLimit / eV << " eV - " |
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| 61 | << highEnergyLimit / keV << " keV" |
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| 62 | << G4endl; |
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| 63 | |
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| 64 | } |
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| 65 | |
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| 66 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 67 | |
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| 68 | G4DNAChampionElasticModel::~G4DNAChampionElasticModel() |
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| 69 | { |
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| 70 | // For total cross section |
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| 71 | |
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| 72 | std::map< G4String,G4DNACrossSectionDataSet*,std::less<G4String> >::iterator pos; |
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| 73 | for (pos = tableData.begin(); pos != tableData.end(); ++pos) |
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| 74 | { |
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| 75 | G4DNACrossSectionDataSet* table = pos->second; |
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| 76 | delete table; |
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| 77 | } |
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| 78 | |
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| 79 | // For final state |
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| 80 | |
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| 81 | eVecm.clear(); |
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| 82 | |
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| 83 | } |
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| 84 | |
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| 85 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 86 | |
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| 87 | void G4DNAChampionElasticModel::Initialise(const G4ParticleDefinition* /*particle*/, |
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| 88 | const G4DataVector& /*cuts*/) |
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| 89 | { |
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| 90 | |
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| 91 | if (verboseLevel > 3) |
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| 92 | G4cout << "Calling G4DNAChampionElasticModel::Initialise()" << G4endl; |
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| 93 | |
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| 94 | // Energy limits |
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| 95 | |
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| 96 | if (LowEnergyLimit() < lowEnergyLimit) |
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| 97 | { |
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| 98 | G4cout << "G4DNAChampionElasticModel: low energy limit increased from " << |
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| 99 | LowEnergyLimit()/eV << " eV to " << lowEnergyLimit/eV << " eV" << G4endl; |
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| 100 | SetLowEnergyLimit(lowEnergyLimit); |
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| 101 | } |
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| 102 | |
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| 103 | if (HighEnergyLimit() > highEnergyLimit) |
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| 104 | { |
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| 105 | G4cout << "G4DNAChampionElasticModel: high energy limit decreased from " << |
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| 106 | HighEnergyLimit()/keV << " keV to " << highEnergyLimit/keV << " keV" << G4endl; |
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| 107 | SetHighEnergyLimit(highEnergyLimit); |
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| 108 | } |
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| 109 | |
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| 110 | // Reading of data files |
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| 111 | |
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| 112 | G4double scaleFactor = 1e-16*cm*cm; |
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| 113 | |
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| 114 | G4String fileElectron("dna/sigma_elastic_e_champion"); |
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| 115 | |
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| 116 | G4ParticleDefinition* electronDef = G4Electron::ElectronDefinition(); |
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| 117 | G4String electron; |
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| 118 | |
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| 119 | if (electronDef != 0) |
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| 120 | { |
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| 121 | // For total cross section |
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| 122 | |
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| 123 | electron = electronDef->GetParticleName(); |
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| 124 | |
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| 125 | tableFile[electron] = fileElectron; |
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| 126 | |
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| 127 | G4DNACrossSectionDataSet* tableE = new G4DNACrossSectionDataSet(new G4LogLogInterpolation, eV,scaleFactor ); |
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| 128 | tableE->LoadData(fileElectron); |
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| 129 | tableData[electron] = tableE; |
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| 130 | |
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| 131 | // For final state |
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| 132 | |
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| 133 | char *path = getenv("G4LEDATA"); |
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| 134 | |
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| 135 | if (!path) |
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| 136 | G4Exception("G4FinalStateElasticChampion::Initialise: G4LEDATA environment variable not set"); |
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| 137 | |
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| 138 | std::ostringstream eFullFileName; |
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| 139 | eFullFileName << path << "/dna/sigmadiff_elastic_e_champion.dat"; |
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| 140 | std::ifstream eDiffCrossSection(eFullFileName.str().c_str()); |
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| 141 | |
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| 142 | if (!eDiffCrossSection) G4Exception("G4DNAChampionElasticModel::Initialise: error opening electron DATA FILE"); |
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| 143 | |
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| 144 | eTdummyVec.push_back(0.); |
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| 145 | |
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| 146 | while(!eDiffCrossSection.eof()) |
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| 147 | { |
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| 148 | double tDummy; |
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| 149 | double eDummy; |
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| 150 | eDiffCrossSection>>tDummy>>eDummy; |
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| 151 | |
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| 152 | // SI : mandatory eVecm initialization |
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| 153 | if (tDummy != eTdummyVec.back()) |
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| 154 | { |
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| 155 | eTdummyVec.push_back(tDummy); |
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| 156 | eVecm[tDummy].push_back(0.); |
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| 157 | } |
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| 158 | |
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| 159 | eDiffCrossSection>>eDiffCrossSectionData[tDummy][eDummy]; |
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| 160 | |
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| 161 | // SI : only if not end of file reached ! |
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| 162 | if (!eDiffCrossSection.eof()) eDiffCrossSectionData[tDummy][eDummy]*=scaleFactor; |
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| 163 | |
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| 164 | if (eDummy != eVecm[tDummy].back()) eVecm[tDummy].push_back(eDummy); |
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| 165 | |
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| 166 | } |
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| 167 | |
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| 168 | // End final state |
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| 169 | |
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| 170 | } |
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| 171 | else G4Exception("G4DNAChampionElasticModel::Initialise: electron is not defined"); |
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| 172 | |
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| 173 | if (verboseLevel > 2) |
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| 174 | G4cout << "Loaded cross section files for Champion Elastic model" << G4endl; |
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| 175 | |
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| 176 | G4cout << "Champion Elastic model is initialized " << G4endl |
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| 177 | << "Energy range: " |
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| 178 | << LowEnergyLimit() / eV << " eV - " |
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| 179 | << HighEnergyLimit() / keV << " keV" |
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| 180 | << G4endl; |
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| 181 | |
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| 182 | if(!isInitialised) |
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| 183 | { |
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| 184 | isInitialised = true; |
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| 185 | |
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| 186 | if(pParticleChange) |
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| 187 | fParticleChangeForGamma = reinterpret_cast<G4ParticleChangeForGamma*>(pParticleChange); |
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| 188 | else |
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| 189 | fParticleChangeForGamma = new G4ParticleChangeForGamma(); |
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| 190 | } |
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| 191 | |
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| 192 | // InitialiseElementSelectors(particle,cuts); |
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| 193 | |
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| 194 | // Test if water material |
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| 195 | |
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| 196 | flagMaterialIsWater= false; |
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| 197 | densityWater = 0; |
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| 198 | |
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| 199 | const G4ProductionCutsTable* theCoupleTable = G4ProductionCutsTable::GetProductionCutsTable(); |
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| 200 | |
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| 201 | if(theCoupleTable) |
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| 202 | { |
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| 203 | G4int numOfCouples = theCoupleTable->GetTableSize(); |
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| 204 | |
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| 205 | if(numOfCouples>0) |
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| 206 | { |
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| 207 | for (G4int i=0; i<numOfCouples; i++) |
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| 208 | { |
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| 209 | const G4MaterialCutsCouple* couple = theCoupleTable->GetMaterialCutsCouple(i); |
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| 210 | const G4Material* material = couple->GetMaterial(); |
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| 211 | |
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| 212 | size_t j = material->GetNumberOfElements(); |
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| 213 | while (j>0) |
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| 214 | { |
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| 215 | j--; |
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| 216 | const G4Element* element(material->GetElement(j)); |
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| 217 | if (element->GetZ() == 8.) |
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| 218 | { |
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| 219 | G4double density = material->GetAtomicNumDensityVector()[j]; |
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| 220 | if (density > 0.) |
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| 221 | { |
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| 222 | flagMaterialIsWater = true; |
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| 223 | densityWater = density; |
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| 224 | |
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| 225 | if (verboseLevel > 3) |
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| 226 | G4cout << "Water material is found with density(cm^-3)=" << density/(cm*cm*cm) << G4endl; |
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| 227 | } |
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| 228 | } |
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| 229 | } |
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| 230 | |
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| 231 | } |
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| 232 | } // if(numOfCouples>0) |
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| 233 | |
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| 234 | } // if (theCoupleTable) |
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| 235 | |
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| 236 | } |
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| 237 | |
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| 238 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 239 | |
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| 240 | G4double G4DNAChampionElasticModel::CrossSectionPerVolume(const G4Material*, |
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| 241 | const G4ParticleDefinition* p, |
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| 242 | G4double ekin, |
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| 243 | G4double, |
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| 244 | G4double) |
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| 245 | { |
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| 246 | if (verboseLevel > 3) |
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| 247 | G4cout << "Calling CrossSectionPerVolume() of G4DNAChampionElasticModel" << G4endl; |
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| 248 | |
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| 249 | // Calculate total cross section for model |
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| 250 | |
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| 251 | G4double sigma=0; |
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| 252 | |
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| 253 | if (flagMaterialIsWater) |
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| 254 | { |
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| 255 | const G4String& particleName = p->GetParticleName(); |
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| 256 | |
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| 257 | if (ekin >= lowEnergyLimitOfModel && ekin < highEnergyLimit) |
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| 258 | { |
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| 259 | std::map< G4String,G4DNACrossSectionDataSet*,std::less<G4String> >::iterator pos; |
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| 260 | pos = tableData.find(particleName); |
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| 261 | |
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| 262 | if (pos != tableData.end()) |
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| 263 | { |
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| 264 | G4DNACrossSectionDataSet* table = pos->second; |
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| 265 | if (table != 0) |
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| 266 | { |
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| 267 | sigma = table->FindValue(ekin); |
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| 268 | } |
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| 269 | } |
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| 270 | else |
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| 271 | { |
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| 272 | G4Exception("G4DNAChampionElasticModel::ComputeCrossSectionPerVolume: attempting to calculate cross section for wrong particle"); |
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| 273 | } |
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| 274 | } |
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| 275 | |
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| 276 | if (verboseLevel > 3) |
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| 277 | { |
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| 278 | G4cout << "---> Kinetic energy(eV)=" << ekin/eV << G4endl; |
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| 279 | G4cout << " - Cross section per water molecule (cm^2)=" << sigma/cm/cm << G4endl; |
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| 280 | G4cout << " - Cross section per water molecule (cm^-1)=" << sigma*densityWater/(1./cm) << G4endl; |
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| 281 | } |
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| 282 | |
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| 283 | } // if (flagMaterialIsWater) |
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| 284 | |
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| 285 | return sigma*densityWater; |
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| 286 | } |
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| 287 | |
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| 288 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 289 | |
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| 290 | void G4DNAChampionElasticModel::SampleSecondaries(std::vector<G4DynamicParticle*>* /*fvect*/, |
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| 291 | const G4MaterialCutsCouple* /*couple*/, |
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| 292 | const G4DynamicParticle* aDynamicElectron, |
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| 293 | G4double, |
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| 294 | G4double) |
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| 295 | { |
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| 296 | |
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| 297 | if (verboseLevel > 3) |
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| 298 | G4cout << "Calling SampleSecondaries() of G4DNAChampionElasticModel" << G4endl; |
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| 299 | |
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| 300 | G4double electronEnergy0 = aDynamicElectron->GetKineticEnergy(); |
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| 301 | |
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| 302 | if (electronEnergy0 < killBelowEnergy) |
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| 303 | { |
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| 304 | fParticleChangeForGamma->ProposeTrackStatus(fStopAndKill); |
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| 305 | fParticleChangeForGamma->ProposeLocalEnergyDeposit(electronEnergy0); |
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| 306 | return ; |
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| 307 | } |
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| 308 | |
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| 309 | if (electronEnergy0>= killBelowEnergy && electronEnergy0 < highEnergyLimit) |
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| 310 | { |
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| 311 | G4double cosTheta = RandomizeCosTheta(electronEnergy0); |
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| 312 | |
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| 313 | G4double phi = 2. * pi * G4UniformRand(); |
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| 314 | |
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| 315 | G4ThreeVector zVers = aDynamicElectron->GetMomentumDirection(); |
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| 316 | G4ThreeVector xVers = zVers.orthogonal(); |
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| 317 | G4ThreeVector yVers = zVers.cross(xVers); |
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| 318 | |
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| 319 | G4double xDir = std::sqrt(1. - cosTheta*cosTheta); |
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| 320 | G4double yDir = xDir; |
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| 321 | xDir *= std::cos(phi); |
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| 322 | yDir *= std::sin(phi); |
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| 323 | |
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| 324 | G4ThreeVector zPrimeVers((xDir*xVers + yDir*yVers + cosTheta*zVers)); |
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| 325 | |
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| 326 | fParticleChangeForGamma->ProposeMomentumDirection(zPrimeVers.unit()) ; |
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| 327 | |
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| 328 | fParticleChangeForGamma->SetProposedKineticEnergy(electronEnergy0); |
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| 329 | } |
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| 330 | |
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| 331 | } |
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| 332 | |
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| 333 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 334 | |
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| 335 | G4double G4DNAChampionElasticModel::DifferentialCrossSection |
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| 336 | (G4ParticleDefinition * particleDefinition, G4double k, G4double theta) |
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| 337 | { |
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| 338 | |
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| 339 | G4double sigma = 0.; |
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| 340 | G4double valueT1 = 0; |
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| 341 | G4double valueT2 = 0; |
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| 342 | G4double valueE21 = 0; |
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| 343 | G4double valueE22 = 0; |
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| 344 | G4double valueE12 = 0; |
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| 345 | G4double valueE11 = 0; |
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| 346 | G4double xs11 = 0; |
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| 347 | G4double xs12 = 0; |
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| 348 | G4double xs21 = 0; |
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| 349 | G4double xs22 = 0; |
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| 350 | |
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| 351 | //SI : ensure the correct computation of cross section at the 180*deg limit |
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| 352 | if (theta==180.) theta=theta-1e-9; |
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| 353 | |
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| 354 | if (particleDefinition == G4Electron::ElectronDefinition()) |
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| 355 | { |
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| 356 | std::vector<double>::iterator t2 = std::upper_bound(eTdummyVec.begin(),eTdummyVec.end(), k); |
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| 357 | std::vector<double>::iterator t1 = t2-1; |
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| 358 | |
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| 359 | std::vector<double>::iterator e12 = std::upper_bound(eVecm[(*t1)].begin(),eVecm[(*t1)].end(), theta); |
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| 360 | std::vector<double>::iterator e11 = e12-1; |
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| 361 | |
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| 362 | std::vector<double>::iterator e22 = std::upper_bound(eVecm[(*t2)].begin(),eVecm[(*t2)].end(), theta); |
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| 363 | std::vector<double>::iterator e21 = e22-1; |
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| 364 | |
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| 365 | valueT1 =*t1; |
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| 366 | valueT2 =*t2; |
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| 367 | valueE21 =*e21; |
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| 368 | valueE22 =*e22; |
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| 369 | valueE12 =*e12; |
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| 370 | valueE11 =*e11; |
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| 371 | |
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| 372 | xs11 = eDiffCrossSectionData[valueT1][valueE11]; |
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| 373 | xs12 = eDiffCrossSectionData[valueT1][valueE12]; |
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| 374 | xs21 = eDiffCrossSectionData[valueT2][valueE21]; |
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| 375 | xs22 = eDiffCrossSectionData[valueT2][valueE22]; |
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| 376 | |
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| 377 | } |
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| 378 | |
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| 379 | G4double xsProduct = xs11 * xs12 * xs21 * xs22; |
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| 380 | |
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| 381 | if (xs11==0 || xs12==0 ||xs21==0 ||xs22==0) return (0.); |
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| 382 | |
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| 383 | if (xsProduct != 0.) |
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| 384 | { |
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| 385 | sigma = QuadInterpolator( valueE11, valueE12, |
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| 386 | valueE21, valueE22, |
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| 387 | xs11, xs12, |
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| 388 | xs21, xs22, |
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| 389 | valueT1, valueT2, |
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| 390 | k, theta ); |
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| 391 | } |
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| 392 | |
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| 393 | return sigma; |
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| 394 | } |
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| 395 | |
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| 396 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 397 | |
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| 398 | G4double G4DNAChampionElasticModel::LinLogInterpolate(G4double e1, |
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| 399 | G4double e2, |
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| 400 | G4double e, |
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| 401 | G4double xs1, |
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| 402 | G4double xs2) |
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| 403 | { |
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| 404 | G4double d1 = std::log(xs1); |
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| 405 | G4double d2 = std::log(xs2); |
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| 406 | G4double value = std::exp(d1 + (d2 - d1)*(e - e1)/ (e2 - e1)); |
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| 407 | return value; |
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| 408 | } |
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| 409 | |
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| 410 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 411 | |
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| 412 | G4double G4DNAChampionElasticModel::LogLogInterpolate(G4double e1, |
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| 413 | G4double e2, |
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| 414 | G4double e, |
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| 415 | G4double xs1, |
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| 416 | G4double xs2) |
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| 417 | { |
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| 418 | G4double a = (std::log10(xs2)-std::log10(xs1)) / (std::log10(e2)-std::log10(e1)); |
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| 419 | G4double b = std::log10(xs2) - a*std::log10(e2); |
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| 420 | G4double sigma = a*std::log10(e) + b; |
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| 421 | G4double value = (std::pow(10.,sigma)); |
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| 422 | return value; |
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| 423 | } |
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| 424 | |
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| 425 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 426 | |
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| 427 | G4double G4DNAChampionElasticModel::QuadInterpolator(G4double e11, G4double e12, |
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| 428 | G4double e21, G4double e22, |
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| 429 | G4double xs11, G4double xs12, |
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| 430 | G4double xs21, G4double xs22, |
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| 431 | G4double t1, G4double t2, |
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| 432 | G4double t, G4double e) |
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| 433 | { |
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| 434 | // Log-Log |
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| 435 | /* |
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| 436 | G4double interpolatedvalue1 = LogLogInterpolate(e11, e12, e, xs11, xs12); |
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| 437 | G4double interpolatedvalue2 = LogLogInterpolate(e21, e22, e, xs21, xs22); |
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| 438 | G4double value = LogLogInterpolate(t1, t2, t, interpolatedvalue1, interpolatedvalue2); |
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| 439 | */ |
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| 440 | |
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| 441 | // Lin-Log |
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| 442 | G4double interpolatedvalue1 = LinLogInterpolate(e11, e12, e, xs11, xs12); |
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| 443 | G4double interpolatedvalue2 = LinLogInterpolate(e21, e22, e, xs21, xs22); |
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| 444 | G4double value = LinLogInterpolate(t1, t2, t, interpolatedvalue1, interpolatedvalue2); |
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| 445 | return value; |
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| 446 | } |
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| 447 | |
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| 448 | //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo.... |
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| 449 | |
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| 450 | G4double G4DNAChampionElasticModel::RandomizeCosTheta(G4double k) |
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| 451 | { |
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| 452 | // ***** Similar method as for screened Rutherford scattering |
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| 453 | |
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| 454 | G4int iMax=180; |
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| 455 | G4double max=0; |
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| 456 | G4double tmp=0; |
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| 457 | |
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| 458 | // Look for maximum : |
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| 459 | for (G4int i=0; i<iMax; i++) |
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| 460 | { |
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| 461 | tmp = DifferentialCrossSection(G4Electron::ElectronDefinition(),k/eV,G4double(i)*180./(iMax-1)); |
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| 462 | if (tmp>max) max = tmp; |
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| 463 | } |
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| 464 | |
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| 465 | G4double oneOverMax=0; |
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| 466 | if (max!=0) oneOverMax = 1./max; |
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| 467 | |
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| 468 | G4double cosTheta = 0.; |
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| 469 | G4double fCosTheta = 0.; |
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| 470 | |
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| 471 | do |
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| 472 | { |
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| 473 | cosTheta = 2. * G4UniformRand() - 1.; |
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| 474 | fCosTheta = oneOverMax * DifferentialCrossSection(G4Electron::ElectronDefinition(),k/eV,std::acos(cosTheta)*180./pi); |
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| 475 | } |
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| 476 | while (fCosTheta < G4UniformRand()); |
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| 477 | |
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| 478 | if (verboseLevel > 3) |
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| 479 | { |
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| 480 | G4cout << "---> Cos(theta)=" << cosTheta << G4endl; |
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| 481 | } |
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| 482 | |
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| 483 | return cosTheta; |
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| 484 | } |
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