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: G4RPGFragmentation.cc,v 1.6 2008/06/09 18:13:16 dennis Exp $ |
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27 | // GEANT4 tag $Name: geant4-09-03-ref-09 $ |
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28 | // |
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29 | |
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30 | #include "G4RPGFragmentation.hh" |
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31 | #include "G4AntiProton.hh" |
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32 | #include "G4AntiNeutron.hh" |
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33 | #include "Randomize.hh" |
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34 | #include "G4Poisson.hh" |
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35 | #include <iostream> |
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36 | #include "G4HadReentrentException.hh" |
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37 | #include <signal.h> |
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38 | |
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39 | |
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40 | G4RPGFragmentation::G4RPGFragmentation() |
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41 | : G4RPGReaction() {} |
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42 | |
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43 | |
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44 | void G4RPGFragmentation:: |
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45 | FragmentationIntegral(G4double pt, G4double et, G4double parMass, G4double secMass) |
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46 | { |
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47 | pt = std::max( 0.001, pt ); |
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48 | G4double dx = 1./(19.*pt); |
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49 | G4double x; |
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50 | G4double term1; |
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51 | G4double term2; |
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52 | |
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53 | for (G4int i = 1; i < 20; i++) { |
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54 | x = (G4double(i) - 0.5)*dx; |
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55 | term1 = 1. + parMass*parMass*x*x; |
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56 | term2 = pt*x*et*pt*x*et + pt*pt + secMass*secMass; |
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57 | dndl[i] = dx / std::sqrt( term1*term1*term1*term2 ) |
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58 | + dndl[i-1]; |
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59 | } |
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60 | } |
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61 | |
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62 | |
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63 | G4bool G4RPGFragmentation:: |
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64 | ReactionStage(const G4HadProjectile* originalIncident, |
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65 | G4ReactionProduct& modifiedOriginal, |
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66 | G4bool& incidentHasChanged, |
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67 | const G4DynamicParticle* originalTarget, |
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68 | G4ReactionProduct& targetParticle, |
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69 | G4bool& targetHasChanged, |
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70 | const G4Nucleus& targetNucleus, |
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71 | G4ReactionProduct& currentParticle, |
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72 | G4FastVector<G4ReactionProduct,256>& vec, |
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73 | G4int& vecLen, |
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74 | G4bool leadFlag, |
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75 | G4ReactionProduct& leadingStrangeParticle) |
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76 | { |
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77 | // |
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78 | // Based on H. Fesefeldt's original FORTRAN code GENXPT |
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79 | // |
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80 | // Generation of x- and pT- values for incident, target, and all secondary |
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81 | // particles using a simple single variable description E D3S/DP3= F(Q) |
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82 | // with Q^2 = (M*X)^2 + PT^2. Final state kinematics are produced by an |
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83 | // FF-type iterative cascade method |
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84 | // |
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85 | // Internal units are GeV |
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86 | // |
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87 | |
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88 | // Protection in case no secondary has been created. In that case use |
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89 | // two-body scattering |
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90 | // |
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91 | if (vecLen == 0) return false; |
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92 | |
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93 | G4ParticleDefinition* aPiMinus = G4PionMinus::PionMinus(); |
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94 | G4ParticleDefinition* aProton = G4Proton::Proton(); |
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95 | G4ParticleDefinition* aNeutron = G4Neutron::Neutron(); |
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96 | G4ParticleDefinition* aPiPlus = G4PionPlus::PionPlus(); |
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97 | G4ParticleDefinition* aPiZero = G4PionZero::PionZero(); |
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98 | |
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99 | G4int i, l; |
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100 | G4bool veryForward = false; |
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101 | |
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102 | const G4double ekOriginal = modifiedOriginal.GetKineticEnergy()/GeV; |
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103 | const G4double etOriginal = modifiedOriginal.GetTotalEnergy()/GeV; |
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104 | const G4double mOriginal = modifiedOriginal.GetMass()/GeV; |
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105 | const G4double pOriginal = modifiedOriginal.GetMomentum().mag()/GeV; |
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106 | G4double targetMass = targetParticle.GetDefinition()->GetPDGMass()/GeV; |
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107 | G4double centerofmassEnergy = std::sqrt( mOriginal*mOriginal + |
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108 | targetMass*targetMass + |
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109 | 2.0*targetMass*etOriginal ); // GeV |
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110 | G4double currentMass = currentParticle.GetMass()/GeV; |
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111 | targetMass = targetParticle.GetMass()/GeV; |
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112 | |
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113 | // Randomize the order of the secondary particles. |
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114 | // Note that the current and target particles are not affected. |
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115 | |
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116 | for (i=0; i<vecLen; ++i) { |
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117 | G4int itemp = G4int( G4UniformRand()*vecLen ); |
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118 | G4ReactionProduct pTemp = *vec[itemp]; |
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119 | *vec[itemp] = *vec[i]; |
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120 | *vec[i] = pTemp; |
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121 | } |
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122 | |
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123 | if (currentMass == 0.0 && targetMass == 0.0) { |
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124 | // Target and projectile have annihilated. Replace them with the first |
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125 | // two secondaries in the list. Current particle KE is maintained. |
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126 | |
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127 | G4double ek = currentParticle.GetKineticEnergy(); |
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128 | G4ThreeVector m = currentParticle.GetMomentum(); |
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129 | currentParticle = *vec[0]; |
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130 | currentParticle.SetSide(1); |
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131 | targetParticle = *vec[1]; |
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132 | targetParticle.SetSide(-1); |
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133 | for( i=0; i<(vecLen-2); ++i )*vec[i] = *vec[i+2]; |
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134 | G4ReactionProduct *temp = vec[vecLen-1]; |
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135 | delete temp; |
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136 | temp = vec[vecLen-2]; |
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137 | delete temp; |
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138 | vecLen -= 2; |
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139 | currentMass = currentParticle.GetMass()/GeV; |
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140 | targetMass = targetParticle.GetMass()/GeV; |
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141 | incidentHasChanged = true; |
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142 | targetHasChanged = true; |
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143 | currentParticle.SetKineticEnergy( ek ); |
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144 | currentParticle.SetMomentum( m ); |
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145 | veryForward = true; |
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146 | } |
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147 | const G4double atomicWeight = targetNucleus.GetN(); |
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148 | const G4double atomicNumber = targetNucleus.GetZ(); |
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149 | const G4double protonMass = aProton->GetPDGMass(); |
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150 | |
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151 | if (originalIncident->GetDefinition()->GetParticleSubType() == "kaon" |
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152 | && G4UniformRand() >= 0.7) { |
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153 | G4ReactionProduct temp = currentParticle; |
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154 | currentParticle = targetParticle; |
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155 | targetParticle = temp; |
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156 | incidentHasChanged = true; |
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157 | targetHasChanged = true; |
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158 | currentMass = currentParticle.GetMass()/GeV; |
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159 | targetMass = targetParticle.GetMass()/GeV; |
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160 | } |
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161 | const G4double afc = std::min( 0.75, |
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162 | 0.312+0.200*std::log(std::log(centerofmassEnergy*centerofmassEnergy))+ |
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163 | std::pow(centerofmassEnergy*centerofmassEnergy,1.5)/6000.0 ); |
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164 | |
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165 | G4double freeEnergy = centerofmassEnergy-currentMass-targetMass; |
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166 | G4double forwardEnergy = freeEnergy/2.; |
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167 | G4int forwardCount = 1; // number of particles in forward hemisphere |
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168 | |
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169 | G4double backwardEnergy = freeEnergy/2.; |
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170 | G4int backwardCount = 1; // number of particles in backward hemisphere |
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171 | |
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172 | if(veryForward) { |
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173 | if(currentParticle.GetSide()==-1) |
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174 | { |
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175 | forwardEnergy += currentMass; |
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176 | forwardCount --; |
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177 | backwardEnergy -= currentMass; |
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178 | backwardCount ++; |
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179 | } |
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180 | if(targetParticle.GetSide()!=-1) |
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181 | { |
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182 | backwardEnergy += targetMass; |
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183 | backwardCount --; |
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184 | forwardEnergy -= targetMass; |
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185 | forwardCount ++; |
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186 | } |
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187 | } |
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188 | |
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189 | for (i=0; i<vecLen; ++i) { |
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190 | if( vec[i]->GetSide() == -1 ) |
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191 | { |
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192 | ++backwardCount; |
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193 | backwardEnergy -= vec[i]->GetMass()/GeV; |
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194 | } else { |
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195 | ++forwardCount; |
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196 | forwardEnergy -= vec[i]->GetMass()/GeV; |
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197 | } |
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198 | } |
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199 | |
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200 | // Check that sum of forward particle masses does not exceed forwardEnergy, |
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201 | // and similarly for backward particles. If so, move particles from one |
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202 | // hemisphere to another. |
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203 | |
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204 | if (backwardEnergy < 0.0) { |
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205 | for (i = 0; i < vecLen; ++i) { |
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206 | if (vec[i]->GetSide() == -1) { |
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207 | backwardEnergy += vec[i]->GetMass()/GeV; |
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208 | --backwardCount; |
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209 | vec[i]->SetSide(1); |
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210 | forwardEnergy -= vec[i]->GetMass()/GeV; |
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211 | ++forwardCount; |
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212 | if (backwardEnergy > 0.0) break; |
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213 | } |
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214 | } |
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215 | } |
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216 | |
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217 | if (forwardEnergy < 0.0) { |
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218 | for (i = 0; i < vecLen; ++i) { |
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219 | if (vec[i]->GetSide() == 1) { |
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220 | forwardEnergy += vec[i]->GetMass()/GeV; |
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221 | --forwardCount; |
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222 | vec[i]->SetSide(-1); |
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223 | backwardEnergy -= vec[i]->GetMass()/GeV; |
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224 | ++backwardCount; |
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225 | if (forwardEnergy > 0.0) break; |
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226 | } |
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227 | } |
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228 | } |
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229 | |
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230 | // Special cases for reactions near threshold |
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231 | |
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232 | // 1. There is only one secondary |
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233 | if (forwardEnergy > 0.0 && backwardEnergy < 0.0) { |
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234 | forwardEnergy += backwardEnergy; |
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235 | backwardEnergy = 0; |
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236 | } |
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237 | |
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238 | // 2. Nuclear binding energy is large |
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239 | if (forwardEnergy + backwardEnergy < 0.0) return false; |
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240 | |
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241 | |
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242 | // forwardEnergy now represents the total energy in the forward reaction |
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243 | // hemisphere which is available for kinetic energy and particle creation. |
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244 | // Similarly for backwardEnergy. |
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245 | |
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246 | // Add particles from the intranuclear cascade. |
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247 | // nuclearExcitationCount = number of new secondaries produced by nuclear |
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248 | // excitation |
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249 | // extraCount = number of nucleons within these new secondaries |
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250 | // |
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251 | // Note: eventually have to make sure that enough nucleons are available |
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252 | // in the case of small target nuclei |
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253 | |
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254 | G4double xtarg; |
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255 | if( centerofmassEnergy < (2.0+G4UniformRand()) ) |
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256 | xtarg = afc * (std::pow(atomicWeight,0.33)-1.0) * (2.0*backwardCount+vecLen+2)/2.0; |
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257 | else |
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258 | xtarg = afc * (std::pow(atomicWeight,0.33)-1.0) * (2.0*backwardCount); |
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259 | if( xtarg <= 0.0 )xtarg = 0.01; |
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260 | G4int nuclearExcitationCount = G4Poisson( xtarg ); |
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261 | // To do: try reducing nuclearExcitationCount with increasing energy |
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262 | // to simulate cut-off of cascade |
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263 | if(atomicWeight<1.0001) nuclearExcitationCount = 0; |
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264 | G4int extraNucleonCount = 0; |
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265 | G4double extraNucleonMass = 0.0; |
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266 | |
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267 | if (nuclearExcitationCount > 0) { |
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268 | const G4double nucsup[] = { 1.00, 0.7, 0.5, 0.4, 0.35, 0.3 }; |
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269 | const G4double psup[] = { 3., 6., 20., 50., 100., 1000. }; |
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270 | G4int momentumBin = 0; |
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271 | while( (momentumBin < 6) && |
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272 | (modifiedOriginal.GetTotalMomentum()/GeV > psup[momentumBin]) ) |
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273 | ++momentumBin; |
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274 | momentumBin = std::min( 5, momentumBin ); |
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275 | |
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276 | // NOTE: in GENXPT, these new particles were given negative codes |
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277 | // here I use NewlyAdded = true instead |
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278 | // |
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279 | |
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280 | for (i = 0; i < nuclearExcitationCount; ++i) { |
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281 | G4ReactionProduct * pVec = new G4ReactionProduct(); |
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282 | if (G4UniformRand() < nucsup[momentumBin]) { |
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283 | |
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284 | if (G4UniformRand() > 1.0-atomicNumber/atomicWeight) |
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285 | pVec->SetDefinition( aProton ); |
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286 | else |
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287 | pVec->SetDefinition( aNeutron ); |
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288 | |
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289 | // nucleon comes from nucleus - |
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290 | // do not subtract its mass from backward energy |
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291 | pVec->SetSide( -2 ); // -2 means backside nucleon |
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292 | ++extraNucleonCount; |
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293 | extraNucleonMass += pVec->GetMass()/GeV; |
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294 | // To do: Remove chosen nucleon from target nucleus |
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295 | pVec->SetNewlyAdded( true ); |
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296 | vec.SetElement( vecLen++, pVec ); |
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297 | ++backwardCount; |
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298 | |
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299 | } else { |
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300 | |
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301 | G4double ran = G4UniformRand(); |
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302 | if( ran < 0.3181 ) |
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303 | pVec->SetDefinition( aPiPlus ); |
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304 | else if( ran < 0.6819 ) |
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305 | pVec->SetDefinition( aPiZero ); |
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306 | else |
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307 | pVec->SetDefinition( aPiMinus ); |
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308 | |
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309 | if (backwardEnergy > pVec->GetMass()/GeV) { |
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310 | backwardEnergy -= pVec->GetMass()/GeV; // pion mass comes from free energy |
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311 | ++backwardCount; |
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312 | pVec->SetSide( -1 ); // backside particle, but not a nucleon |
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313 | pVec->SetNewlyAdded( true ); |
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314 | vec.SetElement( vecLen++, pVec ); |
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315 | } |
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316 | |
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317 | // To do: Change proton to neutron (or vice versa) in target nucleus depending |
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318 | // on pion charge |
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319 | } |
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320 | } |
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321 | } |
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322 | |
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323 | // Define initial state vectors for Lorentz transformations |
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324 | // The pseudoParticles have non-standard masses, hence the "pseudo" |
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325 | |
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326 | G4ReactionProduct pseudoParticle[8]; |
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327 | for (i = 0; i < 8; ++i) pseudoParticle[i].SetZero(); |
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328 | |
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329 | pseudoParticle[0].SetMass( mOriginal*GeV ); |
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330 | pseudoParticle[0].SetMomentum( 0.0, 0.0, pOriginal*GeV ); |
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331 | pseudoParticle[0].SetTotalEnergy( |
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332 | std::sqrt( pOriginal*pOriginal + mOriginal*mOriginal )*GeV ); |
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333 | |
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334 | pseudoParticle[1].SetMass(protonMass); // this could be targetMass |
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335 | pseudoParticle[1].SetTotalEnergy(protonMass); |
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336 | |
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337 | pseudoParticle[3].SetMass(protonMass*(1+extraNucleonCount) ); |
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338 | pseudoParticle[3].SetTotalEnergy(protonMass*(1+extraNucleonCount) ); |
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339 | |
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340 | pseudoParticle[2] = pseudoParticle[0] + pseudoParticle[1]; |
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341 | pseudoParticle[3] = pseudoParticle[3] + pseudoParticle[0]; |
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342 | |
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343 | pseudoParticle[0].Lorentz( pseudoParticle[0], pseudoParticle[2] ); |
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344 | pseudoParticle[1].Lorentz( pseudoParticle[1], pseudoParticle[2] ); |
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345 | |
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346 | // Main loop for 4-momentum generation |
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347 | // See Pitha-report (Aachen) for a detailed description of the method |
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348 | |
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349 | G4double aspar, pt, et, x, pp, pp1, wgt; |
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350 | G4int innerCounter, outerCounter; |
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351 | G4bool eliminateThisParticle, resetEnergies, constantCrossSection; |
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352 | |
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353 | G4double forwardKinetic = 0.0; |
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354 | G4double backwardKinetic = 0.0; |
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355 | |
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356 | // Process the secondary particles in reverse order |
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357 | // The incident particle is done after the secondaries |
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358 | // Nucleons, including the target, in the backward hemisphere are also |
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359 | // done later |
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360 | |
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361 | G4int backwardNucleonCount = 0; // number of nucleons in backward hemisphere |
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362 | G4double totalEnergy, kineticEnergy, vecMass; |
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363 | G4double phi; |
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364 | |
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365 | for (i = vecLen-1; i >= 0; --i) { |
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366 | |
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367 | if (vec[i]->GetNewlyAdded()) { // added from intranuclear cascade |
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368 | if (vec[i]->GetSide() == -2) { // its a nucleon |
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369 | if (backwardNucleonCount < 18) { |
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370 | if (vec[i]->GetDefinition()->GetParticleSubType() == "pi") { |
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371 | for(G4int i=0; i<vecLen; i++) delete vec[i]; |
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372 | vecLen = 0; |
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373 | throw G4HadReentrentException(__FILE__, __LINE__, |
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374 | "G4RPGFragmentation::ReactionStage : a pion has been counted as a backward nucleon"); |
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375 | } |
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376 | vec[i]->SetSide(-3); |
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377 | ++backwardNucleonCount; |
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378 | continue; // Don't generate momenta for the first 17 backward |
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379 | // cascade nucleons. This gets done by the cluster |
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380 | // model later on. |
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381 | } |
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382 | } |
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383 | } |
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384 | |
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385 | // Set pt and phi values, they are changed somewhat in the iteration loop |
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386 | // Set mass parameter for lambda fragmentation model |
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387 | |
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388 | vecMass = vec[i]->GetMass()/GeV; |
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389 | G4double ran = -std::log(1.0-G4UniformRand())/3.5; |
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390 | |
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391 | if (vec[i]->GetSide() == -2) { // backward nucleon |
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392 | aspar = 0.20; |
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393 | pt = std::sqrt( std::pow( ran, 1.2 ) ); |
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394 | |
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395 | } else { // not a backward nucleon |
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396 | if (vec[i]->GetDefinition()->GetParticleSubType() == "pi") { |
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397 | aspar = 0.75; |
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398 | pt = std::sqrt( std::pow( ran, 1.7 ) ); |
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399 | } else if (vec[i]->GetDefinition()->GetParticleSubType() == "kaon") { |
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400 | aspar = 0.70; |
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401 | pt = std::sqrt( std::pow( ran, 1.7 ) ); |
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402 | } else { // vec[i] must be a baryon or ion |
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403 | aspar = 0.65; |
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404 | pt = std::sqrt( std::pow( ran, 1.5 ) ); |
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405 | } |
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406 | } |
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407 | |
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408 | pt = std::max( 0.001, pt ); |
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409 | phi = G4UniformRand()*twopi; |
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410 | vec[i]->SetMomentum( pt*std::cos(phi)*GeV, pt*std::sin(phi)*GeV ); |
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411 | if (vec[i]->GetSide() > 0) |
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412 | et = pseudoParticle[0].GetTotalEnergy()/GeV; |
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413 | else |
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414 | et = pseudoParticle[1].GetTotalEnergy()/GeV; |
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415 | |
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416 | // |
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417 | // Start of outer iteration loop |
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418 | // |
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419 | outerCounter = 0; |
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420 | eliminateThisParticle = true; |
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421 | resetEnergies = true; |
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422 | dndl[0] = 0.0; |
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423 | |
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424 | while (++outerCounter < 3) { |
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425 | |
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426 | FragmentationIntegral(pt, et, aspar, vecMass); |
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427 | innerCounter = 0; |
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428 | vec[i]->SetMomentum( pt*std::cos(phi)*GeV, pt*std::sin(phi)*GeV ); |
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429 | |
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430 | // Start of inner iteration loop |
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431 | |
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432 | while (++innerCounter < 7) { |
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433 | |
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434 | ran = G4UniformRand()*dndl[19]; |
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435 | l = 1; |
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436 | while( ( ran > dndl[l] ) && ( l < 19 ) ) l++; |
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437 | x = (G4double(l-1) + G4UniformRand())/19.; |
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438 | if (vec[i]->GetSide() < 0) x *= -1.; |
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439 | vec[i]->SetMomentum( x*et*GeV ); // set the z-momentum |
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440 | totalEnergy = std::sqrt( x*et*x*et + pt*pt + vecMass*vecMass ); |
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441 | vec[i]->SetTotalEnergy( totalEnergy*GeV ); |
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442 | kineticEnergy = vec[i]->GetKineticEnergy()/GeV; |
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443 | |
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444 | if (vec[i]->GetSide() > 0) { // forward side |
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445 | if( (forwardKinetic+kineticEnergy) < 0.95*forwardEnergy ) { |
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446 | // Leave at least 5% of the forward free energy for the projectile |
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447 | |
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448 | pseudoParticle[4] = pseudoParticle[4] + (*vec[i]); |
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449 | forwardKinetic += kineticEnergy; |
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450 | outerCounter = 2; // leave outer loop |
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451 | eliminateThisParticle = false; // don't eliminate this particle |
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452 | resetEnergies = false; |
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453 | break; // leave inner loop |
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454 | } |
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455 | if( innerCounter > 5 )break; // leave inner loop |
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456 | if( backwardEnergy >= vecMass ) // switch sides |
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457 | { |
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458 | vec[i]->SetSide(-1); |
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459 | forwardEnergy += vecMass; |
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460 | backwardEnergy -= vecMass; |
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461 | ++backwardCount; |
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462 | } |
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463 | } else { // backward side |
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464 | // if (extraNucleonCount > 19) x = 0.999; |
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465 | // G4double xxx = 0.95+0.05*extraNucleonCount/20.0; |
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466 | // DHW: I think above lines were meant to be as follows: |
---|
467 | G4double xxx = 0.999; |
---|
468 | if (extraNucleonCount < 20) xxx = 0.95+0.05*extraNucleonCount/20.0; |
---|
469 | |
---|
470 | if ((backwardKinetic+kineticEnergy) < xxx*backwardEnergy) { |
---|
471 | pseudoParticle[5] = pseudoParticle[5] + (*vec[i]); |
---|
472 | backwardKinetic += kineticEnergy; |
---|
473 | outerCounter = 2; // leave outer loop |
---|
474 | eliminateThisParticle = false; // don't eliminate this particle |
---|
475 | resetEnergies = false; |
---|
476 | break; // leave inner loop |
---|
477 | } |
---|
478 | if (innerCounter > 5) break; // leave inner loop |
---|
479 | if (forwardEnergy >= vecMass) { // switch sides |
---|
480 | vec[i]->SetSide(1); |
---|
481 | forwardEnergy -= vecMass; |
---|
482 | backwardEnergy += vecMass; |
---|
483 | backwardCount--; |
---|
484 | } |
---|
485 | } |
---|
486 | G4ThreeVector momentum = vec[i]->GetMomentum(); |
---|
487 | vec[i]->SetMomentum( momentum.x() * 0.9, momentum.y() * 0.9 ); |
---|
488 | pt *= 0.9; |
---|
489 | dndl[19] *= 0.9; |
---|
490 | } // closes inner loop |
---|
491 | |
---|
492 | // If we get here, the inner loop has been done 6 times. |
---|
493 | // If necessary, reduce energies of the previously done particles if |
---|
494 | // they are lighter than protons or are in the forward hemisphere. |
---|
495 | // Then continue with outer loop. |
---|
496 | |
---|
497 | if (resetEnergies) |
---|
498 | ReduceEnergiesOfSecondaries(i+1, forwardKinetic, backwardKinetic, |
---|
499 | vec, vecLen, |
---|
500 | pseudoParticle[4], pseudoParticle[5], |
---|
501 | pt); |
---|
502 | |
---|
503 | } // closes outer loop |
---|
504 | |
---|
505 | if (eliminateThisParticle && vec[i]->GetMayBeKilled()) { |
---|
506 | // not enough energy, eliminate this particle |
---|
507 | |
---|
508 | if (vec[i]->GetSide() > 0) { |
---|
509 | --forwardCount; |
---|
510 | forwardEnergy += vecMass; |
---|
511 | } else { |
---|
512 | --backwardCount; |
---|
513 | if (vec[i]->GetSide() == -2) { |
---|
514 | --extraNucleonCount; |
---|
515 | extraNucleonMass -= vecMass; |
---|
516 | } else { |
---|
517 | backwardEnergy += vecMass; |
---|
518 | } |
---|
519 | } |
---|
520 | |
---|
521 | for( G4int j=i; j<(vecLen-1); ++j )*vec[j] = *vec[j+1]; // shift up |
---|
522 | G4ReactionProduct* temp = vec[vecLen-1]; |
---|
523 | delete temp; |
---|
524 | // To do: modify target nucleus according to particle eliminated |
---|
525 | |
---|
526 | if( --vecLen == 0 ){ |
---|
527 | G4cout << " FALSE RETURN DUE TO ENERGY BALANCE " << G4endl; |
---|
528 | return false; |
---|
529 | } // all the secondaries have been eliminated |
---|
530 | } |
---|
531 | } // closes main loop over secondaries |
---|
532 | |
---|
533 | // Re-balance forward and backward energy if possible and if necessary |
---|
534 | |
---|
535 | G4double forwardKEDiff = forwardEnergy - forwardKinetic; |
---|
536 | G4double backwardKEDiff = backwardEnergy - backwardKinetic; |
---|
537 | |
---|
538 | if (forwardKEDiff < 0.0 || backwardKEDiff < 0.0) { |
---|
539 | ReduceEnergiesOfSecondaries(0, forwardKinetic, backwardKinetic, |
---|
540 | vec, vecLen, |
---|
541 | pseudoParticle[4], pseudoParticle[5], |
---|
542 | pt); |
---|
543 | |
---|
544 | forwardKEDiff = forwardEnergy - forwardKinetic; |
---|
545 | backwardKEDiff = backwardEnergy - backwardKinetic; |
---|
546 | if (backwardKEDiff < 0.0) { |
---|
547 | if (forwardKEDiff + backwardKEDiff > 0.0) { |
---|
548 | backwardEnergy = backwardKinetic; |
---|
549 | forwardEnergy += backwardKEDiff; |
---|
550 | forwardKEDiff = forwardEnergy - forwardKinetic; |
---|
551 | backwardKEDiff = 0.0; |
---|
552 | } else { |
---|
553 | G4cout << " False return due to insufficient backward energy " << G4endl; |
---|
554 | return false; |
---|
555 | } |
---|
556 | } |
---|
557 | |
---|
558 | if (forwardKEDiff < 0.0) { |
---|
559 | if (forwardKEDiff + backwardKEDiff > 0.0) { |
---|
560 | forwardEnergy = forwardKinetic; |
---|
561 | backwardEnergy += forwardKEDiff; |
---|
562 | backwardKEDiff = backwardEnergy - backwardKinetic; |
---|
563 | forwardKEDiff = 0.0; |
---|
564 | } else { |
---|
565 | G4cout << " False return due to insufficient forward energy " << G4endl; |
---|
566 | return false; |
---|
567 | } |
---|
568 | } |
---|
569 | } |
---|
570 | |
---|
571 | // Generate momentum for incident (current) particle, which was placed |
---|
572 | // in the forward hemisphere. |
---|
573 | // Set mass parameter for lambda fragmentation model. |
---|
574 | // Set pt and phi values, which are changed somewhat in the iteration loop |
---|
575 | |
---|
576 | G4double ran = -std::log(1.0-G4UniformRand()); |
---|
577 | if (currentParticle.GetDefinition()->GetParticleSubType() == "pi") { |
---|
578 | aspar = 0.60; |
---|
579 | pt = std::sqrt( std::pow( ran/6.0, 1.7 ) ); |
---|
580 | } else if (currentParticle.GetDefinition()->GetParticleSubType() == "kaon") { |
---|
581 | aspar = 0.50; |
---|
582 | pt = std::sqrt( std::pow( ran/5.0, 1.4 ) ); |
---|
583 | } else { |
---|
584 | aspar = 0.40; |
---|
585 | pt = std::sqrt( std::pow( ran/4.0, 1.2 ) ); |
---|
586 | } |
---|
587 | |
---|
588 | phi = G4UniformRand()*twopi; |
---|
589 | currentParticle.SetMomentum(pt*std::cos(phi)*GeV, pt*std::sin(phi)*GeV); |
---|
590 | et = pseudoParticle[0].GetTotalEnergy()/GeV; |
---|
591 | dndl[0] = 0.0; |
---|
592 | vecMass = currentParticle.GetMass()/GeV; |
---|
593 | |
---|
594 | FragmentationIntegral(pt, et, aspar, vecMass); |
---|
595 | |
---|
596 | ran = G4UniformRand()*dndl[19]; |
---|
597 | l = 1; |
---|
598 | while( ( ran > dndl[l] ) && ( l < 19 ) ) l++; |
---|
599 | x = (G4double(l-1) + G4UniformRand())/19.; |
---|
600 | currentParticle.SetMomentum( x*et*GeV ); // set the z-momentum |
---|
601 | |
---|
602 | if (forwardEnergy < forwardKinetic) { |
---|
603 | totalEnergy = vecMass + 0.04*std::fabs(normal()); |
---|
604 | G4cout << " Not enough forward energy: forwardEnergy = " |
---|
605 | << forwardEnergy << " forwardKinetic = " |
---|
606 | << forwardKinetic << " total energy left = " |
---|
607 | << backwardKEDiff + forwardKEDiff << G4endl; |
---|
608 | } else { |
---|
609 | totalEnergy = vecMass + forwardEnergy - forwardKinetic; |
---|
610 | forwardKinetic = forwardEnergy; |
---|
611 | } |
---|
612 | currentParticle.SetTotalEnergy( totalEnergy*GeV ); |
---|
613 | pp = std::sqrt(std::abs( totalEnergy*totalEnergy - vecMass*vecMass) )*GeV; |
---|
614 | pp1 = currentParticle.GetMomentum().mag(); |
---|
615 | |
---|
616 | if (pp1 < 1.0e-6*GeV) { |
---|
617 | G4ThreeVector iso = Isotropic(pp); |
---|
618 | currentParticle.SetMomentum( iso.x(), iso.y(), iso.z() ); |
---|
619 | } else { |
---|
620 | currentParticle.SetMomentum( currentParticle.GetMomentum() * (pp/pp1) ); |
---|
621 | } |
---|
622 | pseudoParticle[4] = pseudoParticle[4] + currentParticle; |
---|
623 | |
---|
624 | // Current particle now finished |
---|
625 | |
---|
626 | // Begin target particle |
---|
627 | |
---|
628 | if (backwardNucleonCount < 18) { |
---|
629 | targetParticle.SetSide(-3); |
---|
630 | ++backwardNucleonCount; |
---|
631 | |
---|
632 | } else { |
---|
633 | // Set pt and phi values, they are changed somewhat in the iteration loop |
---|
634 | // Set mass parameter for lambda fragmentation model |
---|
635 | |
---|
636 | vecMass = targetParticle.GetMass()/GeV; |
---|
637 | ran = -std::log(1.0-G4UniformRand()); |
---|
638 | aspar = 0.40; |
---|
639 | pt = std::max( 0.001, std::sqrt( std::pow( ran/4.0, 1.2 ) ) ); |
---|
640 | phi = G4UniformRand()*twopi; |
---|
641 | targetParticle.SetMomentum(pt*std::cos(phi)*GeV, pt*std::sin(phi)*GeV); |
---|
642 | et = pseudoParticle[1].GetTotalEnergy()/GeV; |
---|
643 | outerCounter = 0; |
---|
644 | innerCounter = 0; |
---|
645 | G4bool marginalEnergy = true; |
---|
646 | dndl[0] = 0.0; |
---|
647 | G4double xxx = 0.999; |
---|
648 | if( extraNucleonCount < 20 ) xxx = 0.95+0.05*extraNucleonCount/20.0; |
---|
649 | G4ThreeVector momentum; |
---|
650 | |
---|
651 | while (++outerCounter < 4) { |
---|
652 | FragmentationIntegral(pt, et, aspar, vecMass); |
---|
653 | |
---|
654 | for (innerCounter = 0; innerCounter < 6; innerCounter++) { |
---|
655 | ran = G4UniformRand()*dndl[19]; |
---|
656 | l = 1; |
---|
657 | while( ( ran > dndl[l] ) && ( l < 19 ) ) l++; |
---|
658 | x = -(G4double(l-1) + G4UniformRand())/19.; |
---|
659 | targetParticle.SetMomentum( x*et*GeV ); // set the z-momentum |
---|
660 | totalEnergy = std::sqrt(x*et*x*et + pt*pt + vecMass*vecMass); |
---|
661 | targetParticle.SetTotalEnergy( totalEnergy*GeV ); |
---|
662 | |
---|
663 | if ((backwardKinetic+totalEnergy-vecMass) < xxx*backwardEnergy) { |
---|
664 | pseudoParticle[5] = pseudoParticle[5] + targetParticle; |
---|
665 | backwardKinetic += totalEnergy - vecMass; |
---|
666 | outerCounter = 3; // leave outer loop |
---|
667 | marginalEnergy = false; |
---|
668 | break; // leave inner loop |
---|
669 | } |
---|
670 | momentum = targetParticle.GetMomentum(); |
---|
671 | targetParticle.SetMomentum(momentum.x() * 0.9, momentum.y() * 0.9); |
---|
672 | pt *= 0.9; |
---|
673 | dndl[19] *= 0.9; |
---|
674 | } |
---|
675 | } |
---|
676 | |
---|
677 | if (marginalEnergy) { |
---|
678 | G4cout << " Extra backward kinetic energy = " |
---|
679 | << 0.999*backwardEnergy - backwardKinetic << G4endl; |
---|
680 | totalEnergy = vecMass + 0.999*backwardEnergy - backwardKinetic; |
---|
681 | targetParticle.SetTotalEnergy(totalEnergy*GeV); |
---|
682 | pp = std::sqrt(std::abs(totalEnergy*totalEnergy - vecMass*vecMass) )*GeV; |
---|
683 | targetParticle.SetMomentum(momentum.x()/0.9, momentum.y()/0.9); |
---|
684 | pp1 = targetParticle.GetMomentum().mag(); |
---|
685 | targetParticle.SetMomentum(targetParticle.GetMomentum() * pp/pp1 ); |
---|
686 | pseudoParticle[5] = pseudoParticle[5] + targetParticle; |
---|
687 | backwardKinetic = 0.999*backwardEnergy; |
---|
688 | } |
---|
689 | |
---|
690 | } |
---|
691 | |
---|
692 | if (backwardEnergy < backwardKinetic) |
---|
693 | G4cout << " Backward Edif = " << backwardEnergy - backwardKinetic << G4endl; |
---|
694 | if (forwardEnergy != forwardKinetic) |
---|
695 | G4cout << " Forward Edif = " << forwardEnergy - forwardKinetic << G4endl; |
---|
696 | |
---|
697 | // Target particle finished. |
---|
698 | // Now produce backward nucleons with a cluster model |
---|
699 | // ps[2] = CM frame of projectile + target |
---|
700 | // ps[3] = sum of projectile + nucleon cluster in lab frame |
---|
701 | // ps[6] = proj + cluster 4-vector boosted into CM frame of proj + targ |
---|
702 | // with secondaries, current and target particles subtracted |
---|
703 | // = total 4-momentum of backward nucleon cluster |
---|
704 | |
---|
705 | pseudoParticle[6].Lorentz( pseudoParticle[3], pseudoParticle[2] ); |
---|
706 | pseudoParticle[6] = pseudoParticle[6] - pseudoParticle[4]; |
---|
707 | pseudoParticle[6] = pseudoParticle[6] - pseudoParticle[5]; |
---|
708 | |
---|
709 | if (backwardNucleonCount == 1) { |
---|
710 | // Target particle is the only backward nucleon. Give it the remainder |
---|
711 | // of the backward kinetic energy. |
---|
712 | |
---|
713 | G4double ekin = |
---|
714 | std::min(backwardEnergy-backwardKinetic, centerofmassEnergy/2.0-protonMass/GeV); |
---|
715 | |
---|
716 | if( ekin < 0.04 )ekin = 0.04 * std::fabs( normal() ); |
---|
717 | vecMass = targetParticle.GetMass()/GeV; |
---|
718 | totalEnergy = ekin + vecMass; |
---|
719 | targetParticle.SetTotalEnergy( totalEnergy*GeV ); |
---|
720 | pp = std::sqrt(std::abs(totalEnergy*totalEnergy - vecMass*vecMass) )*GeV; |
---|
721 | pp1 = pseudoParticle[6].GetMomentum().mag(); |
---|
722 | if (pp1 < 1.0e-6*GeV) { |
---|
723 | G4ThreeVector iso = Isotropic(pp); |
---|
724 | targetParticle.SetMomentum( iso.x(), iso.y(), iso.z() ); |
---|
725 | } else { |
---|
726 | targetParticle.SetMomentum( pseudoParticle[6].GetMomentum() * (pp/pp1)); |
---|
727 | } |
---|
728 | pseudoParticle[5] = pseudoParticle[5] + targetParticle; |
---|
729 | |
---|
730 | } else if (backwardNucleonCount > 1) { |
---|
731 | // Share remaining energy with up to 17 backward nucleons |
---|
732 | |
---|
733 | G4int tempCount = 5; |
---|
734 | if (backwardNucleonCount < 5) tempCount = backwardNucleonCount; |
---|
735 | tempCount -= 2; |
---|
736 | |
---|
737 | G4double clusterMass = 0.; |
---|
738 | if (targetParticle.GetSide() == -3) |
---|
739 | clusterMass = targetParticle.GetMass()/GeV; |
---|
740 | for (i = 0; i < vecLen; ++i) |
---|
741 | if (vec[i]->GetSide() == -3) clusterMass += vec[i]->GetMass()/GeV; |
---|
742 | clusterMass += backwardEnergy - backwardKinetic; |
---|
743 | |
---|
744 | totalEnergy = pseudoParticle[6].GetTotalEnergy()/GeV; |
---|
745 | pseudoParticle[6].SetMass(clusterMass*GeV); |
---|
746 | |
---|
747 | pp = std::sqrt(std::abs(totalEnergy*totalEnergy - |
---|
748 | clusterMass*clusterMass) )*GeV; |
---|
749 | pp1 = pseudoParticle[6].GetMomentum().mag(); |
---|
750 | if (pp1 < 1.0e-6*GeV) { |
---|
751 | G4ThreeVector iso = Isotropic(pp); |
---|
752 | pseudoParticle[6].SetMomentum(iso.x(), iso.y(), iso.z()); |
---|
753 | } else { |
---|
754 | pseudoParticle[6].SetMomentum(pseudoParticle[6].GetMomentum() * (-pp/pp1)); |
---|
755 | } |
---|
756 | |
---|
757 | std::vector<G4ReactionProduct*> tempList; // ptrs to backward nucleons |
---|
758 | if (targetParticle.GetSide() == -3) tempList.push_back(&targetParticle); |
---|
759 | for (i = 0; i < vecLen; ++i) |
---|
760 | if (vec[i]->GetSide() == -3) tempList.push_back(vec[i]); |
---|
761 | |
---|
762 | constantCrossSection = true; |
---|
763 | |
---|
764 | if (tempList.size() > 1) { |
---|
765 | G4int n_entry = 0; |
---|
766 | wgt = GenerateNBodyEventT(pseudoParticle[6].GetMass(), |
---|
767 | constantCrossSection, tempList); |
---|
768 | |
---|
769 | if (targetParticle.GetSide() == -3) { |
---|
770 | targetParticle = *tempList[0]; |
---|
771 | targetParticle.Lorentz(targetParticle, pseudoParticle[6]); |
---|
772 | n_entry++; |
---|
773 | } |
---|
774 | |
---|
775 | for (i = 0; i < vecLen; ++i) { |
---|
776 | if (vec[i]->GetSide() == -3) { |
---|
777 | *vec[i] = *tempList[n_entry]; |
---|
778 | vec[i]->Lorentz(*vec[i], pseudoParticle[6]); |
---|
779 | n_entry++; |
---|
780 | } |
---|
781 | } |
---|
782 | } |
---|
783 | } else return false; |
---|
784 | |
---|
785 | if (vecLen == 0) return false; // all the secondaries have been eliminated |
---|
786 | |
---|
787 | // Lorentz transformation to lab frame |
---|
788 | |
---|
789 | currentParticle.Lorentz( currentParticle, pseudoParticle[1] ); |
---|
790 | targetParticle.Lorentz( targetParticle, pseudoParticle[1] ); |
---|
791 | for (i = 0; i < vecLen; ++i) vec[i]->Lorentz(*vec[i], pseudoParticle[1]); |
---|
792 | |
---|
793 | // Set leading strange particle flag. |
---|
794 | // leadFlag will be true if original particle and incident particle are |
---|
795 | // both strange, in which case the incident particle becomes the leading |
---|
796 | // particle. |
---|
797 | // leadFlag will also be true if the target particle is strange, but the |
---|
798 | // incident particle is not, in which case the target particle becomes the |
---|
799 | // leading particle. |
---|
800 | |
---|
801 | G4bool leadingStrangeParticleHasChanged = true; |
---|
802 | if (leadFlag) |
---|
803 | { |
---|
804 | if (currentParticle.GetDefinition() == leadingStrangeParticle.GetDefinition()) |
---|
805 | leadingStrangeParticleHasChanged = false; |
---|
806 | if (leadingStrangeParticleHasChanged && |
---|
807 | (targetParticle.GetDefinition() == leadingStrangeParticle.GetDefinition()) ) |
---|
808 | leadingStrangeParticleHasChanged = false; |
---|
809 | if( leadingStrangeParticleHasChanged ) |
---|
810 | { |
---|
811 | for( i=0; i<vecLen; i++ ) |
---|
812 | { |
---|
813 | if( vec[i]->GetDefinition() == leadingStrangeParticle.GetDefinition() ) |
---|
814 | { |
---|
815 | leadingStrangeParticleHasChanged = false; |
---|
816 | break; |
---|
817 | } |
---|
818 | } |
---|
819 | } |
---|
820 | if( leadingStrangeParticleHasChanged ) |
---|
821 | { |
---|
822 | G4bool leadTest = |
---|
823 | (leadingStrangeParticle.GetDefinition()->GetParticleSubType() == "kaon" || |
---|
824 | leadingStrangeParticle.GetDefinition()->GetParticleSubType() == "pi"); |
---|
825 | G4bool targetTest = |
---|
826 | (targetParticle.GetDefinition()->GetParticleSubType() == "kaon" || |
---|
827 | targetParticle.GetDefinition()->GetParticleSubType() == "pi"); |
---|
828 | |
---|
829 | // following modified by JLC 22-Oct-97 |
---|
830 | |
---|
831 | if( (leadTest&&targetTest) || !(leadTest||targetTest) ) // both true or both false |
---|
832 | { |
---|
833 | targetParticle.SetDefinitionAndUpdateE( leadingStrangeParticle.GetDefinition() ); |
---|
834 | targetHasChanged = true; |
---|
835 | } |
---|
836 | else |
---|
837 | { |
---|
838 | currentParticle.SetDefinitionAndUpdateE( leadingStrangeParticle.GetDefinition() ); |
---|
839 | incidentHasChanged = false; |
---|
840 | } |
---|
841 | } |
---|
842 | } // end of if( leadFlag ) |
---|
843 | |
---|
844 | // Get number of final state nucleons and nucleons remaining in |
---|
845 | // target nucleus |
---|
846 | |
---|
847 | std::pair<G4int, G4int> finalStateNucleons = |
---|
848 | GetFinalStateNucleons(originalTarget, vec, vecLen); |
---|
849 | |
---|
850 | G4int protonsInFinalState = finalStateNucleons.first; |
---|
851 | G4int neutronsInFinalState = finalStateNucleons.second; |
---|
852 | |
---|
853 | G4int numberofFinalStateNucleons = |
---|
854 | protonsInFinalState + neutronsInFinalState; |
---|
855 | |
---|
856 | if (currentParticle.GetDefinition()->GetBaryonNumber() == 1 && |
---|
857 | targetParticle.GetDefinition()->GetBaryonNumber() == 1 && |
---|
858 | originalIncident->GetDefinition()->GetPDGMass() < |
---|
859 | G4Lambda::Lambda()->GetPDGMass()) |
---|
860 | numberofFinalStateNucleons++; |
---|
861 | |
---|
862 | numberofFinalStateNucleons = std::max(1, numberofFinalStateNucleons); |
---|
863 | |
---|
864 | G4int PinNucleus = std::max(0, |
---|
865 | G4int(targetNucleus.GetZ()) - protonsInFinalState); |
---|
866 | G4int NinNucleus = std::max(0, |
---|
867 | G4int(targetNucleus.GetN()-targetNucleus.GetZ()) - neutronsInFinalState); |
---|
868 | |
---|
869 | pseudoParticle[3].SetMomentum( 0.0, 0.0, pOriginal*GeV ); |
---|
870 | pseudoParticle[3].SetMass( mOriginal*GeV ); |
---|
871 | pseudoParticle[3].SetTotalEnergy( |
---|
872 | std::sqrt( pOriginal*pOriginal + mOriginal*mOriginal )*GeV ); |
---|
873 | |
---|
874 | G4ParticleDefinition * aOrgDef = modifiedOriginal.GetDefinition(); |
---|
875 | G4int diff = 0; |
---|
876 | if(aOrgDef == G4Proton::Proton() || aOrgDef == G4Neutron::Neutron() ) diff = 1; |
---|
877 | if(numberofFinalStateNucleons == 1) diff = 0; |
---|
878 | pseudoParticle[4].SetMomentum( 0.0, 0.0, 0.0 ); |
---|
879 | pseudoParticle[4].SetMass( protonMass*(numberofFinalStateNucleons-diff) ); |
---|
880 | pseudoParticle[4].SetTotalEnergy( protonMass*(numberofFinalStateNucleons-diff) ); |
---|
881 | |
---|
882 | G4double theoreticalKinetic = |
---|
883 | pseudoParticle[3].GetTotalEnergy() + pseudoParticle[4].GetTotalEnergy() - |
---|
884 | currentParticle.GetMass() - targetParticle.GetMass(); |
---|
885 | for (i = 0; i < vecLen; ++i) theoreticalKinetic -= vec[i]->GetMass(); |
---|
886 | |
---|
887 | G4double simulatedKinetic = |
---|
888 | currentParticle.GetKineticEnergy() + targetParticle.GetKineticEnergy(); |
---|
889 | for (i = 0; i < vecLen; ++i) |
---|
890 | simulatedKinetic += vec[i]->GetKineticEnergy(); |
---|
891 | |
---|
892 | pseudoParticle[5] = pseudoParticle[3] + pseudoParticle[4]; |
---|
893 | pseudoParticle[3].Lorentz( pseudoParticle[3], pseudoParticle[5] ); |
---|
894 | pseudoParticle[4].Lorentz( pseudoParticle[4], pseudoParticle[5] ); |
---|
895 | |
---|
896 | pseudoParticle[7].SetZero(); |
---|
897 | pseudoParticle[7] = pseudoParticle[7] + currentParticle; |
---|
898 | pseudoParticle[7] = pseudoParticle[7] + targetParticle; |
---|
899 | for (i = 0; i < vecLen; ++i) |
---|
900 | pseudoParticle[7] = pseudoParticle[7] + *vec[i]; |
---|
901 | |
---|
902 | /* |
---|
903 | // This code does not appear to do anything to the energy or angle spectra |
---|
904 | if( vecLen <= 16 && vecLen > 0 ) |
---|
905 | { |
---|
906 | // must create a new set of ReactionProducts here because GenerateNBody will |
---|
907 | // modify the momenta for the particles, and we don't want to do this |
---|
908 | // |
---|
909 | G4ReactionProduct tempR[130]; |
---|
910 | tempR[0] = currentParticle; |
---|
911 | tempR[1] = targetParticle; |
---|
912 | for( i=0; i<vecLen; ++i )tempR[i+2] = *vec[i]; |
---|
913 | G4FastVector<G4ReactionProduct,256> tempV1; |
---|
914 | tempV1.Initialize( vecLen+2 ); |
---|
915 | G4int tempLen1 = 0; |
---|
916 | for( i=0; i<vecLen+2; ++i )tempV1.SetElement( tempLen1++, &tempR[i] ); |
---|
917 | constantCrossSection = true; |
---|
918 | |
---|
919 | wgt = GenerateNBodyEvent(pseudoParticle[3].GetTotalEnergy() + |
---|
920 | pseudoParticle[4].GetTotalEnergy(), |
---|
921 | constantCrossSection, tempV1, tempLen1); |
---|
922 | if (wgt == -1) { |
---|
923 | G4double Qvalue = 0; |
---|
924 | for (i = 0; i < tempLen1; i++) Qvalue += tempV1[i]->GetMass(); |
---|
925 | wgt = GenerateNBodyEvent(Qvalue, |
---|
926 | constantCrossSection, tempV1, tempLen1); |
---|
927 | } |
---|
928 | if(wgt>-.5) |
---|
929 | { |
---|
930 | theoreticalKinetic = 0.0; |
---|
931 | for( i=0; i<tempLen1; ++i ) |
---|
932 | { |
---|
933 | pseudoParticle[6].Lorentz( *tempV1[i], pseudoParticle[4] ); |
---|
934 | theoreticalKinetic += pseudoParticle[6].GetKineticEnergy(); |
---|
935 | } |
---|
936 | } |
---|
937 | // DEBUGGING --> DumpFrames::DumpFrame(vec, vecLen); |
---|
938 | } |
---|
939 | */ |
---|
940 | |
---|
941 | // |
---|
942 | // Make sure that the kinetic energies are correct |
---|
943 | // |
---|
944 | |
---|
945 | if (simulatedKinetic != 0.0) { |
---|
946 | wgt = theoreticalKinetic/simulatedKinetic; |
---|
947 | theoreticalKinetic = currentParticle.GetKineticEnergy() * wgt; |
---|
948 | simulatedKinetic = theoreticalKinetic; |
---|
949 | currentParticle.SetKineticEnergy(theoreticalKinetic); |
---|
950 | pp = currentParticle.GetTotalMomentum(); |
---|
951 | pp1 = currentParticle.GetMomentum().mag(); |
---|
952 | if (pp1 < 1.0e-6*GeV) { |
---|
953 | G4ThreeVector iso = Isotropic(pp); |
---|
954 | currentParticle.SetMomentum( iso.x(), iso.y(), iso.z() ); |
---|
955 | } else { |
---|
956 | currentParticle.SetMomentum(currentParticle.GetMomentum() * (pp/pp1)); |
---|
957 | } |
---|
958 | |
---|
959 | theoreticalKinetic = targetParticle.GetKineticEnergy() * wgt; |
---|
960 | targetParticle.SetKineticEnergy(theoreticalKinetic); |
---|
961 | simulatedKinetic += theoreticalKinetic; |
---|
962 | pp = targetParticle.GetTotalMomentum(); |
---|
963 | pp1 = targetParticle.GetMomentum().mag(); |
---|
964 | |
---|
965 | if (pp1 < 1.0e-6*GeV) { |
---|
966 | G4ThreeVector iso = Isotropic(pp); |
---|
967 | targetParticle.SetMomentum(iso.x(), iso.y(), iso.z() ); |
---|
968 | } else { |
---|
969 | targetParticle.SetMomentum(targetParticle.GetMomentum() * (pp/pp1) ); |
---|
970 | } |
---|
971 | |
---|
972 | for (i = 0; i < vecLen; ++i ) { |
---|
973 | theoreticalKinetic = vec[i]->GetKineticEnergy() * wgt; |
---|
974 | simulatedKinetic += theoreticalKinetic; |
---|
975 | vec[i]->SetKineticEnergy(theoreticalKinetic); |
---|
976 | pp = vec[i]->GetTotalMomentum(); |
---|
977 | pp1 = vec[i]->GetMomentum().mag(); |
---|
978 | if( pp1 < 1.0e-6*GeV ) { |
---|
979 | G4ThreeVector iso = Isotropic(pp); |
---|
980 | vec[i]->SetMomentum(iso.x(), iso.y(), iso.z() ); |
---|
981 | } else { |
---|
982 | vec[i]->SetMomentum(vec[i]->GetMomentum() * (pp/pp1) ); |
---|
983 | } |
---|
984 | } |
---|
985 | } |
---|
986 | |
---|
987 | // Rotate(numberofFinalStateNucleons, pseudoParticle[3].GetMomentum(), |
---|
988 | // modifiedOriginal, originalIncident, targetNucleus, |
---|
989 | // currentParticle, targetParticle, vec, vecLen ); |
---|
990 | |
---|
991 | // Add black track particles |
---|
992 | // the total number of particles produced is restricted to 198 |
---|
993 | // this may have influence on very high energies |
---|
994 | |
---|
995 | if( atomicWeight >= 1.5 ) |
---|
996 | { |
---|
997 | // npnb is number of proton/neutron black track particles |
---|
998 | // ndta is the number of deuterons, tritons, and alphas produced |
---|
999 | // epnb is the kinetic energy available for proton/neutron black track |
---|
1000 | // particles |
---|
1001 | // edta is the kinetic energy available for deuteron/triton/alpha particles |
---|
1002 | |
---|
1003 | G4int npnb = 0; |
---|
1004 | G4int ndta = 0; |
---|
1005 | |
---|
1006 | G4double epnb, edta; |
---|
1007 | if (veryForward) { |
---|
1008 | epnb = targetNucleus.GetAnnihilationPNBlackTrackEnergy(); |
---|
1009 | edta = targetNucleus.GetAnnihilationDTABlackTrackEnergy(); |
---|
1010 | } else { |
---|
1011 | epnb = targetNucleus.GetPNBlackTrackEnergy(); |
---|
1012 | edta = targetNucleus.GetDTABlackTrackEnergy(); |
---|
1013 | } |
---|
1014 | /* |
---|
1015 | G4ReactionProduct* fudge = new G4ReactionProduct(); |
---|
1016 | fudge->SetDefinition( aProton ); |
---|
1017 | G4double TT = epnb + edta; |
---|
1018 | G4double MM = fudge->GetMass()/GeV; |
---|
1019 | fudge->SetTotalEnergy(MM*GeV + TT*GeV); |
---|
1020 | G4double pzz = std::sqrt(TT*(TT + 2.*MM)); |
---|
1021 | fudge->SetMomentum(0.0, 0.0, pzz*GeV); |
---|
1022 | vec.SetElement(vecLen++, fudge); |
---|
1023 | // G4cout << " Fudge = " << vec[vecLen-1]->GetKineticEnergy()/GeV |
---|
1024 | << G4endl; |
---|
1025 | */ |
---|
1026 | |
---|
1027 | const G4double pnCutOff = 0.001; |
---|
1028 | const G4double dtaCutOff = 0.001; |
---|
1029 | // const G4double kineticMinimum = 1.e-6; |
---|
1030 | // const G4double kineticFactor = -0.010; |
---|
1031 | // G4double sprob = 0.0; // sprob = probability of self-absorption in |
---|
1032 | // heavy molecules |
---|
1033 | // Not currently used (DHW 9 June 2008) const G4double ekIncident = originalIncident->GetKineticEnergy()/GeV; |
---|
1034 | // if (ekIncident >= 5.0) sprob = std::min(1.0, 0.6*std::log(ekIncident-4.0)); |
---|
1035 | if (epnb > pnCutOff) |
---|
1036 | { |
---|
1037 | npnb = G4Poisson((1.5+1.25*numberofFinalStateNucleons)*epnb/(epnb+edta)); |
---|
1038 | if (numberofFinalStateNucleons + npnb > atomicWeight) |
---|
1039 | npnb = G4int(atomicWeight+0.00001 - numberofFinalStateNucleons); |
---|
1040 | npnb = std::min( npnb, 127-vecLen ); |
---|
1041 | } |
---|
1042 | if( edta >= dtaCutOff ) |
---|
1043 | { |
---|
1044 | ndta = G4Poisson((1.5+1.25*numberofFinalStateNucleons)*edta/(epnb+edta)); |
---|
1045 | ndta = std::min( ndta, 127-vecLen ); |
---|
1046 | } |
---|
1047 | if (npnb == 0 && ndta == 0) npnb = 1; |
---|
1048 | |
---|
1049 | AddBlackTrackParticles(epnb, npnb, edta, ndta, modifiedOriginal, |
---|
1050 | PinNucleus, NinNucleus, targetNucleus, |
---|
1051 | vec, vecLen); |
---|
1052 | } |
---|
1053 | |
---|
1054 | // if( centerofmassEnergy <= (4.0+G4UniformRand()) ) |
---|
1055 | // MomentumCheck( modifiedOriginal, currentParticle, targetParticle, |
---|
1056 | // vec, vecLen ); |
---|
1057 | // |
---|
1058 | // calculate time delay for nuclear reactions |
---|
1059 | // |
---|
1060 | |
---|
1061 | if( (atomicWeight >= 1.5) && (atomicWeight <= 230.0) && (ekOriginal <= 0.2) ) |
---|
1062 | currentParticle.SetTOF( |
---|
1063 | 1.0-500.0*std::exp(-ekOriginal/0.04)*std::log(G4UniformRand()) ); |
---|
1064 | else |
---|
1065 | currentParticle.SetTOF( 1.0 ); |
---|
1066 | return true; |
---|
1067 | |
---|
1068 | } |
---|
1069 | |
---|
1070 | |
---|
1071 | void G4RPGFragmentation:: |
---|
1072 | ReduceEnergiesOfSecondaries(G4int startingIndex, |
---|
1073 | G4double& forwardKinetic, |
---|
1074 | G4double& backwardKinetic, |
---|
1075 | G4FastVector<G4ReactionProduct,256>& vec, |
---|
1076 | G4int& vecLen, |
---|
1077 | G4ReactionProduct& forwardPseudoParticle, |
---|
1078 | G4ReactionProduct& backwardPseudoParticle, |
---|
1079 | G4double& pt) |
---|
1080 | { |
---|
1081 | // Reduce energies and pt of secondaries in order to maintain |
---|
1082 | // energy conservation |
---|
1083 | |
---|
1084 | G4double totalEnergy; |
---|
1085 | G4double pp; |
---|
1086 | G4double pp1; |
---|
1087 | G4double px; |
---|
1088 | G4double py; |
---|
1089 | G4double mass; |
---|
1090 | G4ReactionProduct* pVec; |
---|
1091 | G4int i; |
---|
1092 | |
---|
1093 | forwardKinetic = 0.0; |
---|
1094 | backwardKinetic = 0.0; |
---|
1095 | forwardPseudoParticle.SetZero(); |
---|
1096 | backwardPseudoParticle.SetZero(); |
---|
1097 | |
---|
1098 | for (i = startingIndex; i < vecLen; i++) { |
---|
1099 | pVec = vec[i]; |
---|
1100 | if (pVec->GetSide() != -3) { |
---|
1101 | mass = pVec->GetMass(); |
---|
1102 | totalEnergy = 0.95*pVec->GetTotalEnergy() + 0.05*mass; |
---|
1103 | pVec->SetTotalEnergy(totalEnergy); |
---|
1104 | pp = std::sqrt( std::abs( totalEnergy*totalEnergy - mass*mass ) ); |
---|
1105 | pp1 = pVec->GetMomentum().mag(); |
---|
1106 | if (pp1 < 1.0e-6*GeV) { |
---|
1107 | G4ThreeVector iso = Isotropic(pp); |
---|
1108 | pVec->SetMomentum( iso.x(), iso.y(), iso.z() ); |
---|
1109 | } else { |
---|
1110 | pVec->SetMomentum(pVec->GetMomentum() * (pp/pp1) ); |
---|
1111 | } |
---|
1112 | |
---|
1113 | px = pVec->GetMomentum().x(); |
---|
1114 | py = pVec->GetMomentum().y(); |
---|
1115 | pt = std::max(1.0, std::sqrt( px*px + py*py ) )/GeV; |
---|
1116 | if (pVec->GetSide() > 0) { |
---|
1117 | forwardKinetic += pVec->GetKineticEnergy()/GeV; |
---|
1118 | forwardPseudoParticle = forwardPseudoParticle + (*pVec); |
---|
1119 | } else { |
---|
1120 | backwardKinetic += pVec->GetKineticEnergy()/GeV; |
---|
1121 | backwardPseudoParticle = backwardPseudoParticle + (*pVec); |
---|
1122 | } |
---|
1123 | } |
---|
1124 | } |
---|
1125 | } |
---|
1126 | |
---|
1127 | /* end of file */ |
---|