[819] | 1 | // |
---|
| 2 | // ******************************************************************** |
---|
| 3 | // * License and Disclaimer * |
---|
| 4 | // * * |
---|
| 5 | // * The Geant4 software is copyright of the Copyright Holders of * |
---|
| 6 | // * the Geant4 Collaboration. It is provided under the terms and * |
---|
| 7 | // * conditions of the Geant4 Software License, included in the file * |
---|
| 8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
---|
| 9 | // * include a list of copyright holders. * |
---|
| 10 | // * * |
---|
| 11 | // * Neither the authors of this software system, nor their employing * |
---|
| 12 | // * institutes,nor the agencies providing financial support for this * |
---|
| 13 | // * work make any representation or warranty, express or implied, * |
---|
| 14 | // * regarding this software system or assume any liability for its * |
---|
| 15 | // * use. Please see the license in the file LICENSE and URL above * |
---|
| 16 | // * for the full disclaimer and the limitation of liability. * |
---|
| 17 | // * * |
---|
| 18 | // * This code implementation is the result of the scientific and * |
---|
| 19 | // * technical work of the GEANT4 collaboration. * |
---|
| 20 | // * By using, copying, modifying or distributing the software (or * |
---|
| 21 | // * any work based on the software) you agree to acknowledge its * |
---|
| 22 | // * use in resulting scientific publications, and indicate your * |
---|
| 23 | // * acceptance of all terms of the Geant4 Software license. * |
---|
| 24 | // ******************************************************************** |
---|
| 25 | // |
---|
| 26 | // |
---|
| 27 | |
---|
| 28 | #include "globals.hh" |
---|
| 29 | #include "G4ios.hh" |
---|
| 30 | #include "G4HadronicException.hh" |
---|
| 31 | #include "G4Clebsch.hh" |
---|
| 32 | #include "Randomize.hh" |
---|
| 33 | #include "G4Proton.hh" |
---|
| 34 | #include "G4HadTmpUtil.hh" |
---|
| 35 | |
---|
| 36 | G4Clebsch::G4Clebsch() |
---|
| 37 | { |
---|
| 38 | G4int nLogs = 101; |
---|
| 39 | logs.push_back(0.); |
---|
| 40 | G4int i; |
---|
| 41 | for (i=1; i<nLogs; i++) |
---|
| 42 | { |
---|
| 43 | G4double previousLog = logs.back(); |
---|
| 44 | G4double value = previousLog + std::log((G4double)i); |
---|
| 45 | logs.push_back(value); |
---|
| 46 | } |
---|
| 47 | } |
---|
| 48 | |
---|
| 49 | |
---|
| 50 | G4Clebsch::~G4Clebsch() |
---|
| 51 | { } |
---|
| 52 | |
---|
| 53 | |
---|
| 54 | G4bool G4Clebsch::operator==(const G4Clebsch &right) const |
---|
| 55 | { |
---|
| 56 | return (this == (G4Clebsch *) &right); |
---|
| 57 | } |
---|
| 58 | |
---|
| 59 | |
---|
| 60 | G4bool G4Clebsch::operator!=(const G4Clebsch &right) const |
---|
| 61 | { |
---|
| 62 | return (this != (G4Clebsch *) &right); |
---|
| 63 | } |
---|
| 64 | |
---|
| 65 | |
---|
| 66 | const std::vector<G4double>& G4Clebsch::GetLogs() const |
---|
| 67 | { |
---|
| 68 | return logs; |
---|
| 69 | } |
---|
| 70 | |
---|
| 71 | |
---|
| 72 | |
---|
| 73 | G4double G4Clebsch::Weight(G4int isoIn1, G4int iso3In1, |
---|
| 74 | G4int isoIn2, G4int iso3In2, |
---|
| 75 | G4int isoOut1, G4int isoOut2) const |
---|
| 76 | { |
---|
| 77 | G4double value = 0.; |
---|
| 78 | |
---|
| 79 | G4int m = iso3In1 + iso3In2; |
---|
| 80 | |
---|
| 81 | G4int jMinIn = std::max(std::abs(isoIn1 - isoIn2), std::abs(m)); |
---|
| 82 | G4int jMaxIn = isoIn1 + isoIn2; |
---|
| 83 | |
---|
| 84 | G4int jMinOut = std::max(std::abs(isoOut1 - isoOut2), std::abs(m)); |
---|
| 85 | G4int jMaxOut = isoOut1 + isoOut2; |
---|
| 86 | |
---|
| 87 | G4int jMin = std::max(jMinIn,jMinOut); |
---|
| 88 | G4int jMax = std::min(jMaxIn,jMaxOut); |
---|
| 89 | |
---|
| 90 | G4int j; |
---|
| 91 | for (j=jMin; j<=jMax; j+=2) |
---|
| 92 | { |
---|
| 93 | value += ClebschGordan(isoIn1,iso3In1, isoIn2,iso3In2, j); |
---|
| 94 | } |
---|
| 95 | |
---|
| 96 | return value; |
---|
| 97 | } |
---|
| 98 | |
---|
| 99 | |
---|
| 100 | G4double G4Clebsch::ClebschGordan(G4int isoIn1, G4int iso3In1, |
---|
| 101 | G4int isoIn2, G4int iso3In2, |
---|
| 102 | G4int jOut) const |
---|
| 103 | { |
---|
| 104 | // Calculates Clebsch-Gordan coefficient |
---|
| 105 | |
---|
| 106 | G4double j1 = isoIn1 / 2.0; |
---|
| 107 | G4double j2 = isoIn2 / 2.0; |
---|
| 108 | G4double j3 = jOut / 2.0; |
---|
| 109 | |
---|
| 110 | G4double m1 = iso3In1 / 2.0; |
---|
| 111 | G4double m2 = iso3In2 / 2.0; |
---|
| 112 | G4double m3 = - (m1 + m2); |
---|
| 113 | |
---|
| 114 | G4int n = G4lrint(m3+j1+j2+.1); |
---|
| 115 | G4double argument = 2. * j3 + 1.; |
---|
| 116 | if (argument < 0.) |
---|
| 117 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::ClebschGordan - sqrt of negative argument"); |
---|
| 118 | G4double coeff = std::sqrt(argument) / (std::pow(-1.,n)); |
---|
| 119 | G4double clebsch = coeff * Wigner3J(j1,j2,j3, m1,m2,m3); |
---|
| 120 | G4double value = clebsch * clebsch; |
---|
| 121 | |
---|
| 122 | // G4cout << "ClebschGordan(" |
---|
| 123 | // << isoIn1 << "," << iso3In1 << "," |
---|
| 124 | // << isoIn2 << "," << iso3In2 << "," << jOut |
---|
| 125 | // << ") = " << value << G4endl; |
---|
| 126 | |
---|
| 127 | return value; |
---|
| 128 | } |
---|
| 129 | |
---|
| 130 | |
---|
| 131 | G4double G4Clebsch::Wigner3J(G4double j1, G4double j2, G4double j3, |
---|
| 132 | G4double m1, G4double m2, G4double m3) const |
---|
| 133 | { |
---|
| 134 | // Calculates Wigner 3-j symbols |
---|
| 135 | |
---|
| 136 | G4double value = 0.; |
---|
| 137 | |
---|
| 138 | G4double sigma = j1 + j2 + j3; |
---|
| 139 | std::vector<G4double> n; |
---|
| 140 | n.push_back(-j1 + j2 + j3); // n0 |
---|
| 141 | n.push_back(j1 - m1); // n1 |
---|
| 142 | n.push_back(j1 + m1); // n2 |
---|
| 143 | n.push_back(j1 - j2 + j3); // n3 |
---|
| 144 | n.push_back(j2 - m2); // n4 |
---|
| 145 | n.push_back(j2 + m2); // n5 |
---|
| 146 | n.push_back(j1 + j2 - j3); // n6 |
---|
| 147 | n.push_back(j3 - m3); // n7 |
---|
| 148 | n.push_back(j3 + m3); // n8 |
---|
| 149 | |
---|
| 150 | // Some preliminary checks |
---|
| 151 | |
---|
| 152 | G4bool ok = true; |
---|
| 153 | size_t i; |
---|
| 154 | for(i=1; i<=3; i++) |
---|
| 155 | { |
---|
| 156 | G4double sum1 = n[i-1] + n[i+2] + n[i+5]; |
---|
| 157 | G4double sum2 = n[3*i-1] + n[3*i-2] + n[3*i-3]; |
---|
| 158 | if (sum1 != sigma || sum2 != sigma) ok = false; |
---|
| 159 | G4int j; |
---|
| 160 | for(j=1; j<=3; j++) |
---|
| 161 | { |
---|
| 162 | if (n[i+3*j-4] < 0.) ok = false; |
---|
| 163 | } |
---|
| 164 | } |
---|
| 165 | |
---|
| 166 | if (ok) |
---|
| 167 | { |
---|
| 168 | G4int iMin = 1; |
---|
| 169 | G4int jMin = 1; |
---|
| 170 | G4double smallest = n[0]; |
---|
| 171 | |
---|
| 172 | // Find the smallest n |
---|
| 173 | for (i=1; i<=3; i++) |
---|
| 174 | { |
---|
| 175 | G4int j; |
---|
| 176 | for (j=1; j<=3; j++) |
---|
| 177 | { |
---|
| 178 | if (n[i+3*j-4] < smallest) |
---|
| 179 | { |
---|
| 180 | smallest = n[i+3*j-4]; |
---|
| 181 | iMin = i; |
---|
| 182 | jMin = j; |
---|
| 183 | } |
---|
| 184 | } |
---|
| 185 | } |
---|
| 186 | |
---|
| 187 | G4int sign = 1; |
---|
| 188 | |
---|
| 189 | if(iMin > 1) |
---|
| 190 | { |
---|
| 191 | for(G4int j=1; j<=3; ++j) |
---|
| 192 | { |
---|
| 193 | G4double tmp = n[j*3-3]; |
---|
| 194 | n[j*3-3] = n[iMin+j*3-4]; |
---|
| 195 | n[iMin+j*3-4] = tmp; |
---|
| 196 | } |
---|
| 197 | sign = (G4int) std::pow(-1.,sigma); |
---|
| 198 | } |
---|
| 199 | |
---|
| 200 | if (jMin > 1) |
---|
| 201 | { |
---|
| 202 | for(i=1; i<=3; i++) |
---|
| 203 | { |
---|
| 204 | G4double tmp = n[i-1]; |
---|
| 205 | n[i-1] = n[i+jMin*3-4]; |
---|
| 206 | n[i+jMin*3-4] = tmp; |
---|
| 207 | } |
---|
| 208 | sign *= (G4int) std::pow(-1.,sigma); |
---|
| 209 | } |
---|
| 210 | |
---|
| 211 | const std::vector<G4double> logVector = GetLogs(); |
---|
| 212 | size_t n1 = G4lrint(n[0]); |
---|
| 213 | |
---|
| 214 | // Some boundary checks |
---|
| 215 | G4int logEntries = logVector.size() - 1; |
---|
| 216 | for (i=0; i<n.size(); i++) |
---|
| 217 | { |
---|
| 218 | if (n[i] < 0. || n[i] > logEntries) |
---|
| 219 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::Wigner3J - Outside logVector boundaries, n"); |
---|
| 220 | } |
---|
| 221 | |
---|
| 222 | G4double r1 = n[0]; |
---|
| 223 | G4double r2 = n[3]; |
---|
| 224 | G4double r3 = n[6]; |
---|
| 225 | G4double r4 = n[1]; |
---|
| 226 | G4double r5 = n[4]; |
---|
| 227 | G4double r6 = n[7]; |
---|
| 228 | G4double r7 = n[2]; |
---|
| 229 | G4double r8 = n[5]; |
---|
| 230 | G4double r9 = n[8]; |
---|
| 231 | |
---|
| 232 | G4double l1 = logVector[(G4int)r1]; |
---|
| 233 | G4double l2 = logVector[(G4int)r2]; |
---|
| 234 | G4double l3 = logVector[(G4int)r3]; |
---|
| 235 | G4double l4 = logVector[(G4int)r4]; |
---|
| 236 | G4double l5 = logVector[(G4int)r5]; |
---|
| 237 | G4double l6 = logVector[(G4int)r6]; |
---|
| 238 | G4double l7 = logVector[(G4int)r7]; |
---|
| 239 | G4double l8 = logVector[(G4int)r8]; |
---|
| 240 | G4double l9 = logVector[(G4int)r9]; |
---|
| 241 | |
---|
| 242 | G4double sigma1 = sigma + 1.; |
---|
| 243 | if (sigma1 < 0. || sigma1 > logEntries) |
---|
| 244 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::Wigner3J - Outside logVector boundaries, sigma"); |
---|
| 245 | |
---|
| 246 | G4double ls = logVector[static_cast<G4int>(sigma1+.00001)]; |
---|
| 247 | G4double hlp1 = (l2 + l3 + l4 +l7 -ls -l1 -l5 -l9 -l6 -l8) / 2.; |
---|
| 248 | G4int expon = static_cast<G4int>(r6 + r8+.00001); |
---|
| 249 | G4double sgn = std::pow(-1., expon); |
---|
| 250 | G4double coeff = std::exp(hlp1) * sgn; |
---|
| 251 | |
---|
| 252 | G4int n61 = static_cast<G4int>(r6 - r1+.00001); |
---|
| 253 | if (n61 < 0. || n61 > logEntries) |
---|
| 254 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::Wigner3J - Outside logVector boundaries, n61"); |
---|
| 255 | G4int n81 = static_cast<G4int>(r8 - r1+.00001); |
---|
| 256 | if (n81 < 0. || n81 > logEntries) |
---|
| 257 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::Wigner3J - Outside logVector boundaries, n81"); |
---|
| 258 | |
---|
| 259 | G4double hlp2 = l6 - logVector[n61] + l8 - logVector[n81]; |
---|
| 260 | G4double sum = std::exp(hlp2); |
---|
| 261 | std::vector<G4double> s; |
---|
| 262 | s.push_back(sum); |
---|
| 263 | n1 = (size_t)r1; |
---|
| 264 | for (i=1; i<=n1; i++) |
---|
| 265 | { |
---|
| 266 | G4double last = s.back(); |
---|
| 267 | G4double den = i * (r6 - r1 + i) * (r8 - r1 + i); |
---|
| 268 | if (den == 0) |
---|
| 269 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::Wigner3J - divide by zero"); |
---|
| 270 | G4double data = -last * (r1 + 1.0 - i) * (r5 + 1.0 - i) * (r9 + 1. - i) / den; |
---|
| 271 | s.push_back(data); |
---|
| 272 | sum += data; |
---|
| 273 | } |
---|
| 274 | value = coeff * sum * sign; |
---|
| 275 | } // endif ok |
---|
| 276 | else |
---|
| 277 | { |
---|
| 278 | } |
---|
| 279 | |
---|
| 280 | |
---|
| 281 | // G4cout << "Wigner3j(" |
---|
| 282 | // << j1 << "," << j2 << "," << j3 << "," |
---|
| 283 | // << m1 << "," << m2 << "," << m3 << ") = " |
---|
| 284 | // << value |
---|
| 285 | // << G4endl; |
---|
| 286 | |
---|
| 287 | return value; |
---|
| 288 | } |
---|
| 289 | |
---|
| 290 | |
---|
| 291 | |
---|
| 292 | std::vector<G4double> G4Clebsch::GenerateIso3(G4int isoIn1, G4int iso3In1, |
---|
| 293 | G4int isoIn2, G4int iso3In2, |
---|
| 294 | G4int isoA, G4int isoB) const |
---|
| 295 | { |
---|
| 296 | std::vector<G4double> temp; |
---|
| 297 | |
---|
| 298 | // ---- Special cases first ---- |
---|
| 299 | |
---|
| 300 | // Special case, both Jin are zero |
---|
| 301 | if (isoIn1 == 0 && isoIn2 == 0) |
---|
| 302 | { |
---|
| 303 | G4cout << "WARNING: G4Clebsch::GenerateIso3 - both isoIn are zero" << G4endl; |
---|
| 304 | temp.push_back(0.); |
---|
| 305 | temp.push_back(0.); |
---|
| 306 | return temp; |
---|
| 307 | } |
---|
| 308 | |
---|
| 309 | G4int iso3 = iso3In1 + iso3In2; |
---|
| 310 | |
---|
| 311 | // Special case, either Jout is zero |
---|
| 312 | if (isoA == 0) |
---|
| 313 | { |
---|
| 314 | temp.push_back(0.); |
---|
| 315 | temp.push_back(iso3); |
---|
| 316 | return temp; |
---|
| 317 | } |
---|
| 318 | if (isoB == 0) |
---|
| 319 | { |
---|
| 320 | temp.push_back(iso3); |
---|
| 321 | temp.push_back(0.); |
---|
| 322 | return temp; |
---|
| 323 | } |
---|
| 324 | |
---|
| 325 | // Number of possible states, in |
---|
| 326 | G4int jMinIn = std::max(std::abs(isoIn1 - isoIn2), std::abs(iso3)); |
---|
| 327 | G4int jMaxIn = isoIn1 + isoIn2; |
---|
| 328 | |
---|
| 329 | // Number of possible states, out |
---|
| 330 | |
---|
| 331 | G4int jMinOut = 9999; |
---|
| 332 | G4int jTmp, i, j; |
---|
| 333 | |
---|
| 334 | for(i=-1; i<=1; i+=2) |
---|
| 335 | { |
---|
| 336 | for(j=-1; j<=1; j+=2) |
---|
| 337 | { |
---|
| 338 | jTmp= std::abs(i*isoA + j*isoB); |
---|
| 339 | if(jTmp < jMinOut) jMinOut = jTmp; |
---|
| 340 | } |
---|
| 341 | } |
---|
| 342 | jMinOut = std::max(jMinOut, std::abs(iso3)); |
---|
| 343 | G4int jMaxOut = isoA + isoB; |
---|
| 344 | |
---|
| 345 | // Possible in and out common states |
---|
| 346 | G4int jMin = std::max(jMinIn, jMinOut); |
---|
| 347 | G4int jMax = std::min(jMaxIn, jMaxOut); |
---|
| 348 | if (jMin > jMax) |
---|
| 349 | { |
---|
| 350 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::GenerateIso3 - jMin > JMax"); |
---|
| 351 | } |
---|
| 352 | |
---|
| 353 | // Number of possible isospins |
---|
| 354 | G4int nJ = (jMax - jMin) / 2 + 1; |
---|
| 355 | |
---|
| 356 | // A few consistency checks |
---|
| 357 | |
---|
| 358 | if ( (isoIn1 == 0 || isoIn2 == 0) && jMin != jMax ) |
---|
| 359 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::GenerateIso3 - J1 or J2 = 0, but jMin != JMax"); |
---|
| 360 | |
---|
| 361 | // MGP ---- Shall it be a warning or an exception? |
---|
| 362 | if (nJ == 0) |
---|
| 363 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::GenerateIso3 - nJ is zero, no overlap between in and out"); |
---|
| 364 | |
---|
| 365 | // Loop over all possible combinations of isoIn1, isoIn2, iso3In11, iso3In2, jTot |
---|
| 366 | // to get the probability of each of the in-channel couplings |
---|
| 367 | |
---|
| 368 | std::vector<G4double> clebsch; |
---|
| 369 | |
---|
| 370 | for(j=jMin; j<=jMax; j+=2) |
---|
| 371 | { |
---|
| 372 | G4double cg = ClebschGordan(isoIn1, iso3In1, isoIn2, iso3In2, j); |
---|
| 373 | clebsch.push_back(cg); |
---|
| 374 | } |
---|
| 375 | |
---|
| 376 | // Consistency check |
---|
| 377 | if (static_cast<G4int>(clebsch.size()) != nJ) |
---|
| 378 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::GenerateIso3 - nJ inconsistency"); |
---|
| 379 | |
---|
| 380 | G4double sum = clebsch[0]; |
---|
| 381 | |
---|
| 382 | for (j=1; j<nJ; j++) |
---|
| 383 | { |
---|
| 384 | sum += clebsch[j]; |
---|
| 385 | } |
---|
| 386 | // Consistency check |
---|
| 387 | if (sum <= 0.) |
---|
| 388 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::GenerateIso3 - Sum of Clebsch-Gordan probabilities <=0"); |
---|
| 389 | |
---|
| 390 | // Generate a normalized pdf |
---|
| 391 | |
---|
| 392 | std::vector<G4double> clebschPdf; |
---|
| 393 | G4double previous = clebsch[0]; |
---|
| 394 | clebschPdf.push_back(previous/sum); |
---|
| 395 | for (j=1; j<nJ; j++) |
---|
| 396 | { |
---|
| 397 | previous += clebsch[j]; |
---|
| 398 | G4double prob = previous / sum; |
---|
| 399 | clebschPdf.push_back(prob); |
---|
| 400 | } |
---|
| 401 | |
---|
| 402 | // Generate a random jTot according to the Clebsch-Gordan pdf |
---|
| 403 | G4double rand = G4UniformRand(); |
---|
| 404 | G4int jTot = 0; |
---|
| 405 | for (j=0; j<nJ; j++) |
---|
| 406 | { |
---|
| 407 | G4bool found = false; |
---|
| 408 | if (rand < clebschPdf[j]) |
---|
| 409 | { |
---|
| 410 | found = true; |
---|
| 411 | jTot = jMin + 2*j; |
---|
| 412 | } |
---|
| 413 | if (found) break; |
---|
| 414 | } |
---|
| 415 | |
---|
| 416 | // Generate iso3Out |
---|
| 417 | |
---|
| 418 | std::vector<G4double> mMin; |
---|
| 419 | mMin.push_back(-isoA); |
---|
| 420 | mMin.push_back(-isoB); |
---|
| 421 | |
---|
| 422 | std::vector<G4double> mMax; |
---|
| 423 | mMax.push_back(isoA); |
---|
| 424 | mMax.push_back(isoB); |
---|
| 425 | |
---|
| 426 | // Calculate the possible |J_i M_i> combinations and their probability |
---|
| 427 | |
---|
| 428 | std::vector<G4double> m1Out; |
---|
| 429 | std::vector<G4double> m2Out; |
---|
| 430 | |
---|
| 431 | const G4int size = 20; |
---|
| 432 | G4double prbout[size][size]; |
---|
| 433 | |
---|
| 434 | G4int m1pos(0), m2pos(0); |
---|
| 435 | G4int j12; |
---|
| 436 | G4int m1pr(0), m2pr(0); |
---|
| 437 | |
---|
| 438 | sum = 0.; |
---|
| 439 | for(j12 = std::abs(isoA-isoB); j12<=(isoA+isoB); j12+=2) |
---|
| 440 | { |
---|
| 441 | m1pos = -1; |
---|
| 442 | for (m1pr = static_cast<G4int>(mMin[0]+.00001); m1pr <= mMax[0]; m1pr+=2) |
---|
| 443 | { |
---|
| 444 | m1pos++; |
---|
| 445 | if (m1pos >= size) |
---|
| 446 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::GenerateIso3 - m1pos > size"); |
---|
| 447 | m1Out.push_back(m1pr); |
---|
| 448 | m2pos = -1; |
---|
| 449 | for (m2pr = static_cast<G4int>(mMin[1]+.00001); m2pr <= mMax[1]; m2pr+=2) |
---|
| 450 | { |
---|
| 451 | m2pos++; |
---|
| 452 | if (m2pos >= size) |
---|
| 453 | { |
---|
| 454 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::GenerateIso3 - m2pos > size"); |
---|
| 455 | } |
---|
| 456 | m2Out.push_back(m2pr); |
---|
| 457 | |
---|
| 458 | if(m1pr + m2pr == iso3) |
---|
| 459 | { |
---|
| 460 | G4int m12 = m1pr + m2pr; |
---|
| 461 | G4double c12 = ClebschGordan(isoA, m1pr, isoB,m2pr, j12); |
---|
| 462 | G4double c34 = ClebschGordan(0,0,0,0,0); |
---|
| 463 | G4double ctot = ClebschGordan(j12, m12, 0, 0, jTot); |
---|
| 464 | G4double cleb = c12*c34*ctot; |
---|
| 465 | prbout[m1pos][m2pos] = cleb; |
---|
| 466 | sum += cleb; |
---|
| 467 | } |
---|
| 468 | else |
---|
| 469 | { |
---|
| 470 | prbout[m1pos][m2pos] = 0.; |
---|
| 471 | } |
---|
| 472 | } |
---|
| 473 | } |
---|
| 474 | } |
---|
| 475 | |
---|
| 476 | if (sum <= 0.) |
---|
| 477 | throw G4HadronicException(__FILE__, __LINE__, "G4Clebsch::GenerateIso3 - sum (out) <=0"); |
---|
| 478 | |
---|
| 479 | for (i=0; i<size; i++) |
---|
| 480 | { |
---|
| 481 | for (j=0; j<size; j++) |
---|
| 482 | { |
---|
| 483 | prbout[i][j] /= sum; |
---|
| 484 | } |
---|
| 485 | } |
---|
| 486 | |
---|
| 487 | rand = G4UniformRand(); |
---|
| 488 | |
---|
| 489 | G4int m1p, m2p; |
---|
| 490 | |
---|
| 491 | for (m1p=0; m1p<m1pos; m1p++) |
---|
| 492 | { |
---|
| 493 | for (m2p=0; m2p<m2pos; m2p++) |
---|
| 494 | { |
---|
| 495 | if (rand < prbout[m1p][m2p]) |
---|
| 496 | { |
---|
| 497 | temp.push_back(m1Out[m1p]); |
---|
| 498 | temp.push_back(m2Out[m2p]); |
---|
| 499 | return temp; |
---|
| 500 | } |
---|
| 501 | else |
---|
| 502 | { |
---|
| 503 | rand -= prbout[m1p][m2p]; |
---|
| 504 | } |
---|
| 505 | } |
---|
| 506 | } |
---|
| 507 | |
---|
| 508 | throw G4HadronicException(__FILE__, __LINE__, "Should never get here "); |
---|
| 509 | return temp; |
---|
| 510 | } |
---|
| 511 | |
---|
| 512 | |
---|
| 513 | G4double G4Clebsch::NormalizedClebschGordan(G4int J, G4int m, |
---|
| 514 | G4int J1, G4int J2, |
---|
| 515 | G4int m1, G4int m2) const |
---|
| 516 | { |
---|
| 517 | // Calculate the normalized Clebsch-Gordan coefficient, that is the prob |
---|
| 518 | // of isospin decomposition of (J,m) into J1, J2, m1, m2 |
---|
| 519 | |
---|
| 520 | G4double cleb = 0.; |
---|
| 521 | |
---|
| 522 | if(J1 == 0 || J2 == 0) return cleb; |
---|
| 523 | |
---|
| 524 | G4double sum = 0.0; |
---|
| 525 | |
---|
| 526 | // Loop over all J1,J2,Jtot,m1,m2 combinations |
---|
| 527 | |
---|
| 528 | for(G4int m1Current=-J1; m1Current<=J1; m1Current+=2) |
---|
| 529 | { |
---|
| 530 | G4int m2Current = m - m1Current; |
---|
| 531 | |
---|
| 532 | G4double prob = ClebschGordan(J1, m1Current, J2, m2Current, J); |
---|
| 533 | sum += prob; |
---|
| 534 | if (m2Current == m2 && m1Current == m1) cleb += prob; |
---|
| 535 | } |
---|
| 536 | |
---|
| 537 | // Normalize probs to 1 |
---|
| 538 | if (sum > 0.) cleb /= sum; |
---|
| 539 | |
---|
| 540 | return cleb; |
---|
| 541 | } |
---|