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1 // 1 2 // ******************************************* 3 // * License and Disclaimer 4 // * 5 // * The Geant4 software is copyright of th 6 // * the Geant4 Collaboration. It is provided 7 // * conditions of the Geant4 Software License 8 // * LICENSE and available at http://cern.ch/ 9 // * include a list of copyright holders. 10 // * 11 // * Neither the authors of this software syst 12 // * institutes,nor the agencies providing fin 13 // * work make any representation or warran 14 // * regarding this software system or assum 15 // * use. Please see the license in the file 16 // * for the full disclaimer and the limitatio 17 // * 18 // * This code implementation is the result 19 // * technical work of the GEANT4 collaboratio 20 // * By using, copying, modifying or distri 21 // * any work based on the software) you ag 22 // * use in resulting scientific publicati 23 // * acceptance of all terms of the Geant4 Sof 24 // ******************************************* 25 // 26 // 27 // ------------------------------------------- 28 // 29 // GEANT4 Class file 30 // 31 // 32 // File name: G4RDeBremsstrahlungSpectrum 33 // 34 // Author: V.Ivanchenko (Vladimir.Ivanc 35 // 36 // Creation date: 29 September 2001 37 // 38 // Modifications: 39 // 10.10.01 MGP Revision to improve code qua 40 // 15.11.01 VI Update spectrum model Bethe- 41 // 30.05.02 VI Update interpolation between 42 // parametrisation 43 // 21.02.03 V.Ivanchenko Energy bins are d 44 // 28.02.03 V.Ivanchenko Filename is defin 45 // 46 // ------------------------------------------- 47 48 #include "G4RDeBremsstrahlungSpectrum.hh" 49 #include "G4RDBremsstrahlungParameters.hh" 50 #include "Randomize.hh" 51 #include "G4SystemOfUnits.hh" 52 53 54 G4RDeBremsstrahlungSpectrum::G4RDeBremsstrahlu 55 const G4String& name):G4RDVEnergySpectrum(), 56 lowestE(0.1*eV), 57 xp(bins) 58 { 59 length = xp.size(); 60 theBRparam = new G4RDBremsstrahlungParameter 61 62 verbose = 0; 63 } 64 65 66 G4RDeBremsstrahlungSpectrum::~G4RDeBremsstrahl 67 { 68 delete theBRparam; 69 } 70 71 72 G4double G4RDeBremsstrahlungSpectrum::Probabil 73 74 75 76 77 const G 78 { 79 G4double tm = std::min(tmax, e); 80 G4double t0 = std::max(tmin, lowestE); 81 if(t0 >= tm) return 0.0; 82 83 t0 /= e; 84 tm /= e; 85 86 G4double z0 = lowestE/e; 87 G4DataVector p; 88 89 // Access parameters 90 for (size_t i=0; i<=length; i++) { 91 p.push_back(theBRparam->Parameter(i, Z, e) 92 } 93 94 G4double x = IntSpectrum(t0, tm, p); 95 G4double y = IntSpectrum(z0, 1.0, p); 96 97 98 if(1 < verbose) { 99 G4cout << "tcut(MeV)= " << tmin/MeV 100 << "; tMax(MeV)= " << tmax/MeV 101 << "; t0= " << t0 102 << "; tm= " << tm 103 << "; xp[0]= " << xp[0] 104 << "; z= " << z0 105 << "; val= " << x 106 << "; nor= " << y 107 << G4endl; 108 } 109 p.clear(); 110 111 if(y > 0.0) x /= y; 112 else x = 0.0; 113 // if(x < 0.0) x = 0.0; 114 115 return x; 116 } 117 118 119 G4double G4RDeBremsstrahlungSpectrum::AverageE 120 121 122 123 124 const G4ParticleDefinition*) con 125 { 126 G4double tm = std::min(tmax, e); 127 G4double t0 = std::max(tmin, lowestE); 128 if(t0 >= tm) return 0.0; 129 130 t0 /= e; 131 tm /= e; 132 133 G4double z0 = lowestE/e; 134 135 G4DataVector p; 136 137 // Access parameters 138 for (size_t i=0; i<=length; i++) { 139 p.push_back(theBRparam->Parameter(i, Z, 140 } 141 142 G4double x = AverageValue(t0, tm, p); 143 G4double y = IntSpectrum(z0, 1.0, p); 144 145 // Add integrant over lowest energies 146 G4double zmin = tmin/e; 147 if(zmin < t0) { 148 G4double c = std::sqrt(theBRparam->Parame 149 x += p[0]*(t0 - zmin - c*(std::atan(t0/c) 150 } 151 x *= e; 152 153 if(1 < verbose) { 154 G4cout << "tcut(MeV)= " << tmin/MeV 155 << "; tMax(MeV)= " << tmax/MeV 156 << "; e(MeV)= " << e/MeV 157 << "; t0= " << t0 158 << "; tm= " << tm 159 << "; y= " << y 160 << "; x= " << x 161 << G4endl; 162 } 163 p.clear(); 164 165 if(y > 0.0) x /= y; 166 else x = 0.0; 167 // if(x < 0.0) x = 0.0; 168 169 return x; 170 } 171 172 173 G4double G4RDeBremsstrahlungSpectrum::SampleEn 174 175 176 177 178 const G4ParticleDefinition*) cons 179 { 180 G4double tm = std::min(tmax, e); 181 G4double t0 = std::max(tmin, lowestE); 182 if(t0 >= tm) return 0.0; 183 184 t0 /= e; 185 tm /= e; 186 187 G4DataVector p; 188 189 for (size_t i=0; i<=length; i++) { 190 p.push_back(theBRparam->Parameter(i, Z, e) 191 } 192 G4double amaj = std::max(p[length], 1. - (p[ 193 194 G4double amax = std::log(tm); 195 G4double amin = std::log(t0); 196 G4double tgam, q, fun; 197 198 do { 199 G4double x = amin + G4UniformRand()*(amax 200 tgam = std::exp(x); 201 fun = Function(tgam, p); 202 203 if(fun > amaj) { 204 G4cout << "WARNING in G4RDeBremsstra 205 << " Majoranta " << amaj 206 << " < " << fun 207 << G4endl; 208 } 209 210 q = amaj * G4UniformRand(); 211 } while (q > fun); 212 213 tgam *= e; 214 215 p.clear(); 216 217 return tgam; 218 } 219 220 G4double G4RDeBremsstrahlungSpectrum::IntSpect 221 222 const G4DataVector& p) const 223 { 224 G4double x1 = std::min(xMin, xp[0]); 225 G4double x2 = std::min(xMax, xp[0]); 226 G4double sum = 0.0; 227 228 if(x1 < x2) { 229 G4double k = (p[1] - p[0])/(xp[1] - xp[0]) 230 sum += (1. - k*xp[0])*std::log(x2/x1) + k* 231 } 232 233 for (size_t i=0; i<length-1; i++) { 234 x1 = std::max(xMin, xp[i]); 235 x2 = std::min(xMax, xp[i+1]); 236 if(x1 < x2) { 237 G4double z1 = p[i]; 238 G4double z2 = p[i+1]; 239 sum += z2 - z1 + std::log(x2/x1)*(z1*x2 240 } 241 } 242 if(sum < 0.0) sum = 0.0; 243 return sum; 244 } 245 246 G4double G4RDeBremsstrahlungSpectrum::AverageV 247 248 const G4DataVector& p) const 249 { 250 G4double x1 = std::min(xMin, xp[0]); 251 G4double x2 = std::min(xMax, xp[0]); 252 G4double z1 = x1; 253 G4double z2 = x2; 254 G4double sum = 0.0; 255 256 if(x1 < x2) { 257 G4double k = (p[1] - p[0])/(xp[1] - xp[0]) 258 sum += (z2 - z1)*(1. - k*xp[0]); 259 z1 *= x1; 260 z2 *= x2; 261 sum += 0.5*k*(z2 - z1); 262 } 263 264 for (size_t i=0; i<length-1; i++) { 265 x1 = std::max(xMin, xp[i]); 266 x2 = std::min(xMax, xp[i+1]); 267 if(x1 < x2) { 268 z1 = p[i]; 269 z2 = p[i+1]; 270 sum += 0.5*(z2 - z1)*(x2 + x1) + z1*x2 - 271 } 272 } 273 if(sum < 0.0) sum = 0.0; 274 return sum; 275 } 276 277 G4double G4RDeBremsstrahlungSpectrum::Function 278 const G4DataVector& p) const 279 { 280 G4double f = 0.0; 281 282 if(x <= xp[0]) { 283 f = p[0] + (p[1] - p[0])*(x - xp[0])/(xp[1 284 285 } else { 286 287 for (size_t i=0; i<length-1; i++) { 288 289 if(x <= xp[i+1]) { 290 f = p[i] + (p[i+1] - p[i])*(x - xp[i]) 291 break; 292 } 293 } 294 } 295 return f; 296 } 297 298 void G4RDeBremsstrahlungSpectrum::PrintData() 299 { theBRparam->PrintData(); } 300 301 G4double G4RDeBremsstrahlungSpectrum::Excitati 302 { 303 return 0.0; 304 } 305 306 G4double G4RDeBremsstrahlungSpectrum::MaxEnerg 307 G4int, // Z, 308 const G4ParticleDefinition*) 309 { 310 return kineticEnergy; 311 } 312