[819] | 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 | // |
---|
[1340] | 26 | // $Id: G4Generator2BS.cc,v 1.10 2010/10/14 14:01:02 vnivanch Exp $ |
---|
[1347] | 27 | // GEANT4 tag $Name: geant4-09-04-ref-00 $ |
---|
[819] | 28 | // |
---|
| 29 | // ------------------------------------------------------------------- |
---|
| 30 | // |
---|
| 31 | // GEANT4 Class file |
---|
| 32 | // |
---|
| 33 | // |
---|
| 34 | // File name: G4Generator2BS |
---|
| 35 | // |
---|
| 36 | // Author: Andreia Trindade (andreia@lip.pt) |
---|
| 37 | // Pedro Rodrigues (psilva@lip.pt) |
---|
| 38 | // Luis Peralta (luis@lip.pt) |
---|
| 39 | // |
---|
| 40 | // Creation date: 2 June 2003 |
---|
| 41 | // |
---|
| 42 | // Modifications: |
---|
[1340] | 43 | // 02 Jun 2003 First implementation acording with new design |
---|
| 44 | // 05 Nov 2003 MGP Fixed std namespace |
---|
| 45 | // 17 Nov 2003 MGP Fixed compilation problem on Windows |
---|
| 46 | // 12 Oct 2010 V.Ivanchenko Moved RejectionFunction inline, use G4Pow to speadup |
---|
[819] | 47 | // |
---|
| 48 | // Class Description: |
---|
| 49 | // |
---|
[1340] | 50 | // Concrete base class for Bremsstrahlung Angular Distribution Generation |
---|
| 51 | // 2BS Distribution |
---|
[819] | 52 | // |
---|
| 53 | // Class Description: End |
---|
| 54 | // |
---|
| 55 | // ------------------------------------------------------------------- |
---|
| 56 | // |
---|
| 57 | |
---|
| 58 | #include "G4Generator2BS.hh" |
---|
[1340] | 59 | #include "Randomize.hh" |
---|
| 60 | #include "G4Pow.hh" |
---|
[819] | 61 | |
---|
[1340] | 62 | // |
---|
[819] | 63 | |
---|
[1340] | 64 | G4Generator2BS::G4Generator2BS(const G4String&) |
---|
| 65 | : G4VBremAngularDistribution("AngularGen2BS") |
---|
| 66 | { |
---|
| 67 | g4pow = G4Pow::GetInstance(); |
---|
| 68 | } |
---|
| 69 | |
---|
[819] | 70 | // |
---|
| 71 | |
---|
| 72 | G4Generator2BS::~G4Generator2BS() |
---|
[1340] | 73 | {} |
---|
[819] | 74 | |
---|
| 75 | // |
---|
| 76 | |
---|
| 77 | G4double G4Generator2BS::PolarAngle(const G4double initial_energy, |
---|
| 78 | const G4double final_energy, |
---|
| 79 | const G4int Z) |
---|
| 80 | { |
---|
| 81 | |
---|
| 82 | // Adapted from "Improved bremsstrahlung photon angular sampling in the EGS4 code system" |
---|
| 83 | // by Alex F. Bielajew, Rahde Mohan anc Chen-Shou Chui, PIRS-0203 |
---|
| 84 | // Ionizing Radiation Standards |
---|
| 85 | // Institute for National Measurement Standards |
---|
| 86 | // National Research Council of Canada |
---|
| 87 | // Departement of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York |
---|
| 88 | |
---|
| 89 | G4double theta = 0; |
---|
| 90 | |
---|
| 91 | G4double initialTotalEnergy = (initial_energy+electron_mass_c2)/electron_mass_c2; |
---|
| 92 | G4double finalTotalEnergy = (final_energy+electron_mass_c2)/electron_mass_c2; |
---|
| 93 | EnergyRatio = finalTotalEnergy/initialTotalEnergy; |
---|
| 94 | G4double gMaxEnergy = (pi*initialTotalEnergy)*(pi*initialTotalEnergy); |
---|
| 95 | |
---|
[1340] | 96 | //G4double Zeff = std::sqrt(static_cast<G4double>(Z) * (static_cast<G4double>(Z) + 1.0)); |
---|
| 97 | //z = (0.00008116224*(std::pow(Zeff,0.3333333))); |
---|
[819] | 98 | |
---|
[1340] | 99 | // VI speadup |
---|
| 100 | z = 0.00008116224*(g4pow->Z13(Z) + g4pow->Z13(Z+1)); |
---|
| 101 | |
---|
[819] | 102 | // Rejection arguments |
---|
| 103 | rejection_argument1 = (1.0+EnergyRatio*EnergyRatio); |
---|
| 104 | rejection_argument2 = - 2.0*EnergyRatio + 3.0*rejection_argument1; |
---|
| 105 | rejection_argument3 = ((1-EnergyRatio)/(2.0*initialTotalEnergy*EnergyRatio))* |
---|
| 106 | ((1-EnergyRatio)/(2.0*initialTotalEnergy*EnergyRatio)); |
---|
| 107 | |
---|
| 108 | // Calculate rejection function at 0, 1 and Emax |
---|
[1340] | 109 | G4double gfunction0 = RejectionFunction(0.0); |
---|
| 110 | G4double gfunction1 = RejectionFunction(1.0); |
---|
[819] | 111 | G4double gfunctionEmax = RejectionFunction(gMaxEnergy); |
---|
| 112 | |
---|
| 113 | // Calculate Maximum value |
---|
| 114 | G4double gMaximum = std::max(gfunction0,gfunction1); |
---|
| 115 | gMaximum = std::max(gMaximum,gfunctionEmax); |
---|
| 116 | |
---|
| 117 | G4double rand, gfunctionTest, randTest; |
---|
| 118 | |
---|
| 119 | do{ |
---|
| 120 | rand = G4UniformRand(); |
---|
[1340] | 121 | rand /= (1 - rand + 1.0/gMaxEnergy); |
---|
[819] | 122 | gfunctionTest = RejectionFunction(rand); |
---|
| 123 | randTest = G4UniformRand(); |
---|
| 124 | |
---|
[1340] | 125 | } while(randTest*gMaximum > gfunctionTest); |
---|
[819] | 126 | |
---|
| 127 | theta = std::sqrt(rand)/initialTotalEnergy; |
---|
| 128 | |
---|
| 129 | return theta; |
---|
| 130 | } |
---|
[1340] | 131 | |
---|
[819] | 132 | // |
---|
| 133 | |
---|
| 134 | void G4Generator2BS::PrintGeneratorInformation() const |
---|
| 135 | { |
---|
| 136 | G4cout << "\n" << G4endl; |
---|
[1340] | 137 | G4cout << "Bremsstrahlung Angular Generator is 2BS Generator " |
---|
| 138 | << "from 2BS Koch & Motz distribution (Rev Mod Phys 31(4), 920 (1959))" << G4endl; |
---|
[819] | 139 | G4cout << "Sampling algorithm adapted from PIRS-0203" << G4endl; |
---|
| 140 | G4cout << "\n" << G4endl; |
---|
| 141 | } |
---|
| 142 | |
---|