Geant4 Cross Reference |
1 // 2 // ******************************************************************** 3 // * License and Disclaimer * 4 // * * 5 // * The Geant4 software is copyright of the Copyright Holders of * 6 // * the Geant4 Collaboration. It is provided under the terms and * 7 // * conditions of the Geant4 Software License, included in the file * 8 // * LICENSE and available at http://cern.ch/geant4/license . These * 9 // * include a list of copyright holders. * 10 // * * 11 // * Neither the authors of this software system, nor their employing * 12 // * institutes,nor the agencies providing financial support for this * 13 // * work make any representation or warranty, express or implied, * 14 // * regarding this software system or assume any liability for its * 15 // * use. Please see the license in the file LICENSE and URL above * 16 // * for the full disclaimer and the limitation of liability. * 17 // * * 18 // * This code implementation is the result of the scientific and * 19 // * technical work of the GEANT4 collaboration. * 20 // * By using, copying, modifying or distributing the software (or * 21 // * any work based on the software) you agree to acknowledge its * 22 // * use in resulting scientific publications, and indicate your * 23 // * acceptance of all terms of the Geant4 Software license. * 24 // ******************************************************************** 25 // 26 // V. Ivanchenko, 21 April 2023 Data structure class for gamma levels 27 // 28 29 #include "G4ParticleHPNucLevel.hh" 30 31 #include "G4Gamma.hh" 32 #include "G4RandomDirection.hh" 33 #include "Randomize.hh" 34 35 G4ParticleHPNucLevel::G4ParticleHPNucLevel(G4double e) : levelEnergy(e) {} 36 37 void G4ParticleHPNucLevel::AddGamma(G4double e, G4double w, G4int idx) 38 { 39 gammaData x; 40 x.gammaEnergy = e; 41 x.cumProbability = w; 42 x.next = idx; 43 gammas.push_back(x); 44 ++nGammas; 45 } 46 47 void G4ParticleHPNucLevel::Normalize() 48 { 49 if (gammas.empty()) { 50 return; 51 } 52 G4double sum = 0.0; 53 for (auto& gam : gammas) { 54 sum += gam.cumProbability; 55 } 56 if (sum <= 0.0) { 57 return; 58 } 59 60 G4double norm = 1.0 / sum; 61 sum = 0; 62 for (auto& gam : gammas) { 63 sum += norm * gam.cumProbability; 64 gam.cumProbability = sum; 65 } 66 gammas[nGammas - 1].cumProbability = 1.0; 67 } 68 69 G4ReactionProduct* G4ParticleHPNucLevel::GetDecayGamma(G4int& idx) const 70 { 71 if (gammas.empty()) { 72 return nullptr; 73 } 74 G4double q = G4UniformRand(); 75 G4double e = 0.0; 76 for (auto& gam : gammas) { 77 if (q <= gam.cumProbability) { 78 e = gam.gammaEnergy; 79 idx = gam.next; 80 break; 81 } 82 } 83 if (e <= 0.0) { 84 return nullptr; 85 } 86 G4ThreeVector p = G4RandomDirection(); 87 p *= e; 88 auto res = new G4ReactionProduct(G4Gamma::Gamma()); 89 res->SetMomentum(p); 90 res->SetKineticEnergy(e); 91 return res; 92 } 93