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 | //J.M. Quesada (August2008). Based on: |
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27 | // |
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28 | // Hadronic Process: Nuclear De-excitations |
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29 | // by V. Lara (Oct 1998) |
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30 | // |
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31 | // Modif (03 September 2008) by J. M. Quesada for external choice of inverse |
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32 | // cross section option |
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33 | |
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34 | #include "G4AlphaEvaporationProbability.hh" |
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35 | |
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36 | G4AlphaEvaporationProbability::G4AlphaEvaporationProbability() : |
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37 | G4EvaporationProbability(4,2,1,&theCoulombBarrier) // A,Z,Gamma,&theCoumlombBarrier |
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38 | { |
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39 | |
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40 | } |
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41 | |
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42 | |
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43 | G4AlphaEvaporationProbability::G4AlphaEvaporationProbability(const G4AlphaEvaporationProbability &): G4EvaporationProbability() |
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44 | { |
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45 | throw G4HadronicException(__FILE__, __LINE__, "G4AlphaEvaporationProbability::copy_constructor meant to not be accessable"); |
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46 | } |
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47 | |
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48 | |
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49 | |
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50 | |
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51 | const G4AlphaEvaporationProbability & G4AlphaEvaporationProbability:: |
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52 | operator=(const G4AlphaEvaporationProbability &) |
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53 | { |
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54 | throw G4HadronicException(__FILE__, __LINE__, "G4AlphaEvaporationProbability::operator= meant to not be accessable"); |
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55 | return *this; |
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56 | } |
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57 | |
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58 | |
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59 | G4bool G4AlphaEvaporationProbability::operator==(const G4AlphaEvaporationProbability &) const |
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60 | { |
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61 | return false; |
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62 | } |
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63 | |
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64 | G4bool G4AlphaEvaporationProbability::operator!=(const G4AlphaEvaporationProbability &) const |
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65 | { |
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66 | return true; |
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67 | } |
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68 | |
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69 | |
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70 | G4double G4AlphaEvaporationProbability::CalcAlphaParam(const G4Fragment & fragment) |
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71 | { return 1.0 + CCoeficient(static_cast<G4double>(fragment.GetZ()-GetZ()));} |
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72 | |
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73 | G4double G4AlphaEvaporationProbability::CalcBetaParam(const G4Fragment &) |
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74 | { return 0.0; } |
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75 | |
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76 | G4double G4AlphaEvaporationProbability::CCoeficient(const G4double aZ) |
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77 | { |
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78 | // Data comes from |
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79 | // Dostrovsky, Fraenkel and Friedlander |
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80 | // Physical Review, vol 116, num. 3 1959 |
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81 | // |
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82 | // const G4int size = 5; |
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83 | // G4double Zlist[5] = { 10.0, 20.0, 30.0, 50.0, 70.0}; |
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84 | // G4double Calpha[5] = { 0.10, 0.10, 0.10, 0.08, 0.06}; |
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85 | G4double C = 0.0; |
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86 | |
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87 | |
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88 | if (aZ <= 30) { |
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89 | C = 0.10; |
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90 | } else if (aZ <= 50) { |
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91 | C = 0.1 + -((aZ-50.)/20.)*0.02; |
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92 | } else if (aZ < 70) { |
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93 | C = 0.08 + -((aZ-70.)/20.)*0.02; |
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94 | } else { |
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95 | C = 0.06; |
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96 | } |
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97 | return C; |
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98 | } |
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99 | |
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100 | /////////////////////////////////////////////////////////////////////////////////// |
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101 | //J. M. Quesada (Dec 2007-June 2008): New inverse reaction cross sections |
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102 | //OPT=0 Dostrovski's parameterization |
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103 | //OPT=1,2 Chatterjee's paramaterization |
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104 | //OPT=3,4 Kalbach's parameterization |
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105 | // |
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106 | G4double G4AlphaEvaporationProbability::CrossSection(const G4Fragment & fragment, |
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107 | const G4double K) |
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108 | { |
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109 | theA=GetA(); |
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110 | theZ=GetZ(); |
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111 | ResidualA=fragment.GetA()-theA; |
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112 | ResidualZ=fragment.GetZ()-theZ; |
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113 | |
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114 | ResidualAthrd=std::pow(ResidualA,0.33333); |
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115 | FragmentA=fragment.GetA(); |
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116 | FragmentAthrd=std::pow(FragmentA,0.33333); |
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117 | |
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118 | |
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119 | if (OPTxs==0) {std::ostringstream errOs; |
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120 | errOs << "We should'n be here (OPT =0) at evaporation cross section calculation (Alpha's)!!" |
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121 | <<G4endl; |
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122 | throw G4HadronicException(__FILE__, __LINE__, errOs.str()); |
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123 | return 0.;} |
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124 | |
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125 | if( OPTxs==1 || OPTxs==2) return G4AlphaEvaporationProbability::GetOpt12( K); |
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126 | else if (OPTxs==3 || OPTxs==4) return G4AlphaEvaporationProbability::GetOpt34( K); |
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127 | else{ |
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128 | std::ostringstream errOs; |
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129 | errOs << "BAD Alpha CROSS SECTION OPTION AT EVAPORATION!!" <<G4endl; |
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130 | throw G4HadronicException(__FILE__, __LINE__, errOs.str()); |
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131 | return 0.; |
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132 | } |
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133 | } |
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134 | |
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135 | |
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136 | // |
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137 | //********************* OPT=1,2 : Chatterjee's cross section ************************ |
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138 | //(fitting to cross section from Bechetti & Greenles OM potential) |
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139 | |
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140 | G4double G4AlphaEvaporationProbability::GetOpt12(const G4double K) |
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141 | { |
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142 | // c ** alpha from huizenga and igo |
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143 | G4double Kc=K; |
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144 | |
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145 | // JMQ xsec is set constat above limit of validity |
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146 | if (K>50) Kc=50; |
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147 | |
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148 | G4double landa ,mu ,nu ,p , Ec,q,r,ji,xs; |
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149 | |
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150 | G4double p0 = 10.95; |
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151 | G4double p1 = -85.2; |
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152 | G4double p2 = 1146.; |
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153 | G4double landa0 = 0.0643; |
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154 | G4double landa1 = -13.96; |
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155 | G4double mu0 = 781.2; |
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156 | G4double mu1 = 0.29; |
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157 | G4double nu0 = -304.7; |
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158 | G4double nu1 = -470.0; |
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159 | G4double nu2 = -8.580; |
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160 | G4double delta=1.2; |
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161 | |
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162 | |
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163 | Ec = 1.44*theZ*ResidualZ/(1.5*ResidualAthrd+delta); |
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164 | p = p0 + p1/Ec + p2/(Ec*Ec); |
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165 | landa = landa0*ResidualA + landa1; |
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166 | mu = mu0*std::pow(ResidualA,mu1); |
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167 | nu = std::pow(ResidualA,mu1)*(nu0 + nu1*Ec + nu2*(Ec*Ec)); |
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168 | q = landa - nu/(Ec*Ec) - 2*p*Ec; |
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169 | r = mu + 2*nu/Ec + p*(Ec*Ec); |
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170 | |
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171 | ji=std::max(Kc,Ec); |
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172 | if(Kc < Ec) { xs = p*Kc*Kc + q*Kc + r;} |
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173 | else {xs = p*(Kc - ji)*(Kc - ji) + landa*Kc + mu + nu*(2 - Kc/ji)/ji ;} |
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174 | |
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175 | if (xs <0.0) {xs=0.0;} |
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176 | |
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177 | return xs; |
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178 | |
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179 | } |
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180 | |
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181 | // *********** OPT=3,4 : Kalbach's cross sections (from PRECO code)************* |
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182 | G4double G4AlphaEvaporationProbability::GetOpt34(const G4double K) |
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183 | // c ** alpha from huizenga and igo |
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184 | { |
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185 | |
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186 | G4double landa, mu, nu, p , signor(1.),sig; |
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187 | G4double ec,ecsq,xnulam,etest(0.),a; |
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188 | G4double b,ecut,cut,ecut2,geom,elab; |
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189 | |
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190 | |
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191 | G4double flow = 1.e-18; |
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192 | G4double spill= 1.e+18; |
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193 | |
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194 | G4double p0 = 10.95; |
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195 | G4double p1 = -85.2; |
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196 | G4double p2 = 1146.; |
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197 | G4double landa0 = 0.0643; |
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198 | G4double landa1 = -13.96; |
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199 | G4double mu0 = 781.2; |
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200 | G4double mu1 = 0.29; |
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201 | G4double nu0 = -304.7; |
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202 | G4double nu1 = -470.0; |
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203 | G4double nu2 = -8.580; |
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204 | |
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205 | G4double ra=1.20; |
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206 | |
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207 | //JMQ 13/02/09 increase of reduced radius to lower the barrier |
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208 | // ec = 1.44 * theZ * ResidualZ / (1.5*ResidualAthrd+ra); |
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209 | ec = 1.44 * theZ * ResidualZ / (1.7*ResidualAthrd+ra); |
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210 | ecsq = ec * ec; |
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211 | p = p0 + p1/ec + p2/ecsq; |
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212 | landa = landa0*ResidualA + landa1; |
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213 | a = std::pow(ResidualA,mu1); |
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214 | mu = mu0 * a; |
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215 | nu = a* (nu0+nu1*ec+nu2*ecsq); |
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216 | xnulam = nu / landa; |
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217 | if (xnulam > spill) xnulam=0.; |
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218 | if (xnulam >= flow) etest = 1.2 *std::sqrt(xnulam); |
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219 | |
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220 | a = -2.*p*ec + landa - nu/ecsq; |
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221 | b = p*ecsq + mu + 2.*nu/ec; |
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222 | ecut = 0.; |
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223 | cut = a*a - 4.*p*b; |
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224 | if (cut > 0.) ecut = std::sqrt(cut); |
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225 | ecut = (ecut-a) / (p+p); |
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226 | ecut2 = ecut; |
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227 | if (cut < 0.) ecut2 = ecut - 2.; |
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228 | elab = K * FragmentA / ResidualA; |
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229 | sig = 0.; |
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230 | |
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231 | if (elab <= ec) { //start for E<Ec |
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232 | if (elab > ecut2) sig = (p*elab*elab+a*elab+b) * signor; |
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233 | } //end for E<Ec |
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234 | else { //start for E>Ec |
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235 | sig = (landa*elab+mu+nu/elab) * signor; |
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236 | geom = 0.; |
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237 | if (xnulam < flow || elab < etest) return sig; |
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238 | geom = std::sqrt(theA*K); |
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239 | geom = 1.23*ResidualAthrd + ra + 4.573/geom; |
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240 | geom = 31.416 * geom * geom; |
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241 | sig = std::max(geom,sig); |
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242 | } //end for E>Ec |
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243 | return sig; |
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244 | |
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245 | } |
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246 | |
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247 | // ************************** end of cross sections ******************************* |
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