[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 | // |
---|
[962] | 27 | // $Id: G4CompetitiveFission.cc,v 1.9 2008/11/20 13:46:27 dennis Exp $ |
---|
| 28 | // GEANT4 tag $Name: geant4-09-02-ref-02 $ |
---|
[819] | 29 | // |
---|
| 30 | // Hadronic Process: Nuclear De-excitations |
---|
| 31 | // by V. Lara (Oct 1998) |
---|
| 32 | |
---|
| 33 | #include "G4CompetitiveFission.hh" |
---|
| 34 | #include "G4PairingCorrection.hh" |
---|
| 35 | |
---|
| 36 | G4CompetitiveFission::G4CompetitiveFission() : G4VEvaporationChannel("fission") |
---|
| 37 | { |
---|
| 38 | theFissionBarrierPtr = new G4FissionBarrier; |
---|
| 39 | MyOwnFissionBarrier = true; |
---|
| 40 | |
---|
| 41 | theFissionProbabilityPtr = new G4FissionProbability; |
---|
| 42 | MyOwnFissionProbability = true; |
---|
| 43 | |
---|
| 44 | theLevelDensityPtr = new G4FissionLevelDensityParameter; |
---|
| 45 | MyOwnLevelDensity = true; |
---|
| 46 | |
---|
| 47 | MaximalKineticEnergy = -1000.0*MeV; |
---|
| 48 | FissionBarrier = 0.0; |
---|
| 49 | FissionProbability = 0.0; |
---|
| 50 | LevelDensityParameter = 0.0; |
---|
| 51 | } |
---|
| 52 | |
---|
| 53 | G4CompetitiveFission::G4CompetitiveFission(const G4CompetitiveFission &) : G4VEvaporationChannel() |
---|
| 54 | { |
---|
| 55 | } |
---|
| 56 | |
---|
| 57 | G4CompetitiveFission::~G4CompetitiveFission() |
---|
| 58 | { |
---|
| 59 | if (MyOwnFissionBarrier) delete theFissionBarrierPtr; |
---|
| 60 | |
---|
| 61 | if (MyOwnFissionProbability) delete theFissionProbabilityPtr; |
---|
| 62 | |
---|
| 63 | if (MyOwnLevelDensity) delete theLevelDensityPtr; |
---|
| 64 | } |
---|
| 65 | |
---|
| 66 | const G4CompetitiveFission & G4CompetitiveFission::operator=(const G4CompetitiveFission &) |
---|
| 67 | { |
---|
| 68 | throw G4HadronicException(__FILE__, __LINE__, "G4CompetitiveFission::operator= meant to not be accessable"); |
---|
| 69 | return *this; |
---|
| 70 | } |
---|
| 71 | |
---|
| 72 | G4bool G4CompetitiveFission::operator==(const G4CompetitiveFission &right) const |
---|
| 73 | { |
---|
| 74 | return (this == (G4CompetitiveFission *) &right); |
---|
| 75 | } |
---|
| 76 | |
---|
| 77 | G4bool G4CompetitiveFission::operator!=(const G4CompetitiveFission &right) const |
---|
| 78 | { |
---|
| 79 | return (this != (G4CompetitiveFission *) &right); |
---|
| 80 | } |
---|
| 81 | |
---|
| 82 | |
---|
| 83 | |
---|
| 84 | |
---|
| 85 | void G4CompetitiveFission::Initialize(const G4Fragment & fragment) |
---|
| 86 | { |
---|
| 87 | G4int anA = static_cast<G4int>(fragment.GetA()); |
---|
| 88 | G4int aZ = static_cast<G4int>(fragment.GetZ()); |
---|
| 89 | G4double ExEnergy = fragment.GetExcitationEnergy() - |
---|
| 90 | G4PairingCorrection::GetInstance()->GetFissionPairingCorrection(anA,aZ); |
---|
| 91 | |
---|
| 92 | |
---|
| 93 | // Saddle point excitation energy ---> A = 65 |
---|
| 94 | // Fission is excluded for A < 65 |
---|
| 95 | if (anA >= 65 && ExEnergy > 0.0) { |
---|
| 96 | FissionBarrier = theFissionBarrierPtr->FissionBarrier(anA,aZ,ExEnergy); |
---|
| 97 | MaximalKineticEnergy = ExEnergy - FissionBarrier; |
---|
| 98 | LevelDensityParameter = theLevelDensityPtr->LevelDensityParameter(anA,aZ,ExEnergy); |
---|
| 99 | FissionProbability = theFissionProbabilityPtr->EmissionProbability(fragment,MaximalKineticEnergy); |
---|
| 100 | } |
---|
| 101 | else { |
---|
| 102 | MaximalKineticEnergy = -1000.0*MeV; |
---|
| 103 | LevelDensityParameter = 0.0; |
---|
| 104 | FissionProbability = 0.0; |
---|
| 105 | } |
---|
| 106 | |
---|
| 107 | return; |
---|
| 108 | } |
---|
| 109 | |
---|
| 110 | |
---|
| 111 | |
---|
| 112 | G4FragmentVector * G4CompetitiveFission::BreakUp(const G4Fragment & theNucleus) |
---|
| 113 | { |
---|
| 114 | // Nucleus data |
---|
| 115 | // Atomic number of nucleus |
---|
| 116 | G4int A = static_cast<G4int>(theNucleus.GetA()); |
---|
| 117 | // Charge of nucleus |
---|
| 118 | G4int Z = static_cast<G4int>(theNucleus.GetZ()); |
---|
| 119 | // Excitation energy (in MeV) |
---|
| 120 | G4double U = theNucleus.GetExcitationEnergy() - |
---|
| 121 | G4PairingCorrection::GetInstance()->GetFissionPairingCorrection(A,Z); |
---|
| 122 | // Check that U > 0 |
---|
| 123 | if (U <= 0.0) { |
---|
| 124 | G4FragmentVector * theResult = new G4FragmentVector; |
---|
| 125 | theResult->push_back(new G4Fragment(theNucleus)); |
---|
| 126 | return theResult; |
---|
| 127 | } |
---|
| 128 | |
---|
| 129 | // Atomic Mass of Nucleus (in MeV) |
---|
| 130 | G4double M = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIonMass(Z,A)/MeV; |
---|
| 131 | // Nucleus Momentum |
---|
| 132 | G4LorentzVector theNucleusMomentum = theNucleus.GetMomentum(); |
---|
| 133 | |
---|
| 134 | // Calculate fission parameters |
---|
| 135 | G4FissionParameters theParameters(A,Z,U,FissionBarrier); |
---|
| 136 | |
---|
| 137 | // First fragment |
---|
| 138 | G4int A1 = 0; |
---|
| 139 | G4int Z1 = 0; |
---|
| 140 | G4double M1 = 0.0; |
---|
| 141 | |
---|
| 142 | // Second fragment |
---|
| 143 | G4int A2 = 0; |
---|
| 144 | G4int Z2 = 0; |
---|
| 145 | G4double M2 = 0.0; |
---|
| 146 | |
---|
| 147 | G4double FragmentsExcitationEnergy = 0.0; |
---|
| 148 | G4double FragmentsKineticEnergy = 0.0; |
---|
| 149 | |
---|
| 150 | G4int Trials = 0; |
---|
| 151 | do { |
---|
| 152 | |
---|
| 153 | // First fragment |
---|
| 154 | A1 = FissionAtomicNumber(A,theParameters); |
---|
| 155 | Z1 = FissionCharge(A,Z,A1); |
---|
| 156 | M1 = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIonMass(Z1,A1); |
---|
| 157 | |
---|
| 158 | |
---|
| 159 | // Second Fragment |
---|
| 160 | A2 = A - A1; |
---|
| 161 | Z2 = Z - Z1; |
---|
| 162 | if (A2 < 1 || Z2 < 0) |
---|
| 163 | throw G4HadronicException(__FILE__, __LINE__, "G4CompetitiveFission::BreakUp: Can't define second fragment! "); |
---|
| 164 | M2 = G4ParticleTable::GetParticleTable()->GetIonTable()->GetIonMass(Z2,A2)/MeV; |
---|
| 165 | |
---|
| 166 | // Check that fragment masses are less or equal than total energy |
---|
| 167 | // if (M1 + M2 > theNucleusMomentum.mag()/MeV) |
---|
| 168 | if (M1 + M2 > theNucleusMomentum.e()/MeV) |
---|
| 169 | throw G4HadronicException(__FILE__, __LINE__, "G4CompetitiveFission::BreakUp: Fragments Mass > Total Energy"); |
---|
| 170 | |
---|
| 171 | // Maximal Kinetic Energy (available energy for fragments) |
---|
| 172 | // G4double Tmax = theNucleusMomentum.mag()/MeV - M1 - M2; |
---|
| 173 | G4double Tmax = M + U - M1 - M2; |
---|
| 174 | |
---|
| 175 | FragmentsKineticEnergy = FissionKineticEnergy( A , Z, |
---|
| 176 | A1, Z1, |
---|
| 177 | A2, Z2, |
---|
| 178 | U , Tmax, |
---|
| 179 | theParameters); |
---|
| 180 | |
---|
| 181 | // Excitation Energy |
---|
| 182 | FragmentsExcitationEnergy = Tmax - FragmentsKineticEnergy; |
---|
| 183 | |
---|
| 184 | } while (FragmentsExcitationEnergy < 0.0 && Trials++ < 100); |
---|
| 185 | |
---|
| 186 | |
---|
| 187 | |
---|
| 188 | if (FragmentsExcitationEnergy <= 0.0) |
---|
| 189 | throw G4HadronicException(__FILE__, __LINE__, "G4CompetitiveFission::BreakItUp: Excitation energy for fragments < 0.0!"); |
---|
| 190 | |
---|
| 191 | |
---|
| 192 | // while (FragmentsExcitationEnergy < 0 && Trials < 100); |
---|
| 193 | |
---|
| 194 | // Fragment 1 |
---|
| 195 | G4double U1 = FragmentsExcitationEnergy * (static_cast<G4double>(A1)/static_cast<G4double>(A)); |
---|
| 196 | // Fragment 2 |
---|
| 197 | G4double U2 = FragmentsExcitationEnergy * (static_cast<G4double>(A2)/static_cast<G4double>(A)); |
---|
| 198 | |
---|
| 199 | |
---|
| 200 | G4double Pmax = std::sqrt( 2 * ( ( (M1+U1)*(M2+U2) ) / |
---|
| 201 | ( (M1+U1)+(M2+U2) ) ) * FragmentsKineticEnergy); |
---|
| 202 | |
---|
| 203 | G4ParticleMomentum momentum1 = IsotropicVector( Pmax ); |
---|
| 204 | G4ParticleMomentum momentum2( -momentum1 ); |
---|
| 205 | |
---|
| 206 | // Perform a Galileo boost for fragments |
---|
| 207 | momentum1 += (theNucleusMomentum.boostVector() * (M1+U1)); |
---|
| 208 | momentum2 += (theNucleusMomentum.boostVector() * (M2+U2)); |
---|
| 209 | |
---|
| 210 | |
---|
| 211 | // Create 4-momentum for first fragment |
---|
| 212 | // Warning!! Energy conservation is broken |
---|
| 213 | G4LorentzVector FourMomentum1( momentum1 , std::sqrt(momentum1.mag2() + (M1+U1)*(M1+U1))); |
---|
| 214 | |
---|
| 215 | // Create 4-momentum for second fragment |
---|
| 216 | // Warning!! Energy conservation is broken |
---|
| 217 | G4LorentzVector FourMomentum2( momentum2 , std::sqrt(momentum2.mag2() + (M2+U2)*(M2+U2))); |
---|
| 218 | |
---|
| 219 | // Create Fragments |
---|
| 220 | G4Fragment * Fragment1 = new G4Fragment( A1, Z1, FourMomentum1); |
---|
| 221 | if (!Fragment1) throw G4HadronicException(__FILE__, __LINE__, "G4CompetitiveFission::BreakItUp: Can't create Fragment1! "); |
---|
| 222 | G4Fragment * Fragment2 = new G4Fragment( A2, Z2, FourMomentum2); |
---|
| 223 | if (!Fragment2) throw G4HadronicException(__FILE__, __LINE__, "G4CompetitiveFission::BreakItUp: Can't create Fragment2! "); |
---|
| 224 | |
---|
| 225 | #ifdef PRECOMPOUND_TEST |
---|
| 226 | Fragment1->SetCreatorModel(G4String("G4CompetitiveFission")); |
---|
| 227 | Fragment2->SetCreatorModel(G4String("G4CompetitiveFission")); |
---|
| 228 | #endif |
---|
| 229 | // Create Fragment Vector |
---|
| 230 | G4FragmentVector * theResult = new G4FragmentVector; |
---|
| 231 | |
---|
| 232 | theResult->push_back(Fragment1); |
---|
| 233 | theResult->push_back(Fragment2); |
---|
| 234 | |
---|
| 235 | #ifdef debug |
---|
| 236 | CheckConservation(theNucleus,theResult); |
---|
| 237 | #endif |
---|
| 238 | |
---|
| 239 | return theResult; |
---|
| 240 | } |
---|
| 241 | |
---|
| 242 | |
---|
| 243 | |
---|
| 244 | G4int G4CompetitiveFission::FissionAtomicNumber(const G4int A, const G4FissionParameters & theParam) |
---|
| 245 | // Calculates the atomic number of a fission product |
---|
| 246 | { |
---|
| 247 | |
---|
| 248 | // For Simplicity reading code |
---|
| 249 | const G4double A1 = theParam.GetA1(); |
---|
| 250 | const G4double A2 = theParam.GetA2(); |
---|
| 251 | const G4double As = theParam.GetAs(); |
---|
| 252 | // const G4double Sigma1 = theParam.GetSigma1(); |
---|
| 253 | const G4double Sigma2 = theParam.GetSigma2(); |
---|
| 254 | const G4double SigmaS = theParam.GetSigmaS(); |
---|
| 255 | const G4double w = theParam.GetW(); |
---|
| 256 | |
---|
| 257 | |
---|
| 258 | // G4double FasymAsym = 2.0*std::exp(-((A2-As)*(A2-As))/(2.0*Sigma2*Sigma2)) + |
---|
| 259 | // std::exp(-((A1-As)*(A1-As))/(2.0*Sigma1*Sigma1)); |
---|
| 260 | |
---|
| 261 | // G4double FsymA1A2 = std::exp(-((As-(A1+A2))*(As-(A1+A2)))/(2.0*SigmaS*SigmaS)); |
---|
| 262 | |
---|
| 263 | |
---|
| 264 | G4double C2A = A2 + 3.72*Sigma2; |
---|
| 265 | G4double C2S = As + 3.72*SigmaS; |
---|
| 266 | |
---|
| 267 | G4double C2 = 0.0; |
---|
| 268 | if (w > 1000.0 ) C2 = C2S; |
---|
| 269 | else if (w < 0.001) C2 = C2A; |
---|
| 270 | else C2 = std::max(C2A,C2S); |
---|
| 271 | |
---|
| 272 | G4double C1 = A-C2; |
---|
| 273 | if (C1 < 30.0) { |
---|
| 274 | C2 = A-30.0; |
---|
| 275 | C1 = 30.0; |
---|
| 276 | } |
---|
| 277 | |
---|
| 278 | G4double Am1 = (As + A1)/2.0; |
---|
| 279 | G4double Am2 = (A1 + A2)/2.0; |
---|
| 280 | |
---|
| 281 | // Get Mass distributions as sum of symmetric and asymmetric Gasussians |
---|
| 282 | G4double Mass1 = MassDistribution(As,A,theParam); |
---|
| 283 | G4double Mass2 = MassDistribution(Am1,A,theParam); |
---|
| 284 | G4double Mass3 = MassDistribution(A1,A,theParam); |
---|
| 285 | G4double Mass4 = MassDistribution(Am2,A,theParam); |
---|
| 286 | G4double Mass5 = MassDistribution(A2,A,theParam); |
---|
| 287 | // get maximal value among Mass1,...,Mass5 |
---|
| 288 | G4double MassMax = Mass1; |
---|
| 289 | if (Mass2 > MassMax) MassMax = Mass2; |
---|
| 290 | if (Mass3 > MassMax) MassMax = Mass3; |
---|
| 291 | if (Mass4 > MassMax) MassMax = Mass4; |
---|
| 292 | if (Mass5 > MassMax) MassMax = Mass5; |
---|
| 293 | |
---|
| 294 | // Sample a fragment mass number, which lies between C1 and C2 |
---|
| 295 | G4double m; |
---|
| 296 | G4double Pm; |
---|
| 297 | do { |
---|
| 298 | m = C1+G4UniformRand()*(C2-C1); |
---|
| 299 | Pm = MassDistribution(m,A,theParam); |
---|
| 300 | } while (G4UniformRand() > Pm/MassMax); |
---|
| 301 | |
---|
| 302 | return static_cast<G4int>(m+0.5); |
---|
| 303 | } |
---|
| 304 | |
---|
| 305 | |
---|
| 306 | |
---|
| 307 | |
---|
| 308 | |
---|
| 309 | |
---|
| 310 | G4double G4CompetitiveFission::MassDistribution(const G4double x, const G4double A, |
---|
| 311 | const G4FissionParameters & theParam) |
---|
| 312 | // This method gives mass distribution F(x) = F_{asym}(x)+w*F_{sym}(x) |
---|
| 313 | // which consist of symmetric and asymmetric sum of gaussians components. |
---|
| 314 | { |
---|
| 315 | G4double Xsym = std::exp(-0.5*(x-theParam.GetAs())*(x-theParam.GetAs())/ |
---|
| 316 | (theParam.GetSigmaS()*theParam.GetSigmaS())); |
---|
| 317 | |
---|
| 318 | G4double Xasym = std::exp(-0.5*(x-theParam.GetA2())*(x-theParam.GetA2())/ |
---|
| 319 | (theParam.GetSigma2()*theParam.GetSigma2())) + |
---|
| 320 | std::exp(-0.5*(x-(A-theParam.GetA2()))*(x-(A-theParam.GetA2()))/ |
---|
| 321 | (theParam.GetSigma2()*theParam.GetSigma2())) + |
---|
| 322 | 0.5*std::exp(-0.5*(x-theParam.GetA1())*(x-theParam.GetA1())/ |
---|
| 323 | (theParam.GetSigma1()*theParam.GetSigma1())) + |
---|
| 324 | 0.5*std::exp(-0.5*(x-(A-theParam.GetA1()))*(x-(A-theParam.GetA1()))/ |
---|
| 325 | (theParam.GetSigma1()*theParam.GetSigma1())); |
---|
| 326 | |
---|
| 327 | if (theParam.GetW() > 1000) return Xsym; |
---|
| 328 | else if (theParam.GetW() < 0.001) return Xasym; |
---|
| 329 | else return theParam.GetW()*Xsym+Xasym; |
---|
| 330 | } |
---|
| 331 | |
---|
| 332 | |
---|
| 333 | |
---|
| 334 | |
---|
| 335 | G4int G4CompetitiveFission::FissionCharge(const G4double A, |
---|
| 336 | const G4double Z, |
---|
| 337 | const G4double Af) |
---|
| 338 | // Calculates the charge of a fission product for a given atomic number Af |
---|
| 339 | { |
---|
| 340 | const G4double sigma = 0.6; |
---|
| 341 | G4double DeltaZ = 0.0; |
---|
| 342 | if (Af >= 134.0) DeltaZ = -0.45; // 134 <= Af |
---|
[962] | 343 | else if (Af <= (A-134.0)) DeltaZ = 0.45; // Af <= (A-134) |
---|
[819] | 344 | else DeltaZ = -0.45*(Af-(A/2.0))/(134.0-(A/2.0)); // (A-134) < Af < 134 |
---|
| 345 | |
---|
| 346 | G4double Zmean = (Af/A)*Z + DeltaZ; |
---|
| 347 | |
---|
| 348 | G4double theZ; |
---|
| 349 | do { |
---|
| 350 | theZ = G4RandGauss::shoot(Zmean,sigma); |
---|
| 351 | } while (theZ < 1.0 || theZ > (Z-1.0) || theZ > Af); |
---|
| 352 | // return static_cast<G4int>(theZ+0.5); |
---|
| 353 | return static_cast<G4int>(theZ+0.5); |
---|
| 354 | } |
---|
| 355 | |
---|
| 356 | |
---|
| 357 | |
---|
| 358 | |
---|
| 359 | G4double G4CompetitiveFission::FissionKineticEnergy(const G4double A, const G4double Z, |
---|
| 360 | const G4double Af1, const G4double /*Zf1*/, |
---|
| 361 | const G4double Af2, const G4double /*Zf2*/, |
---|
| 362 | const G4double /*U*/, const G4double Tmax, |
---|
| 363 | const G4FissionParameters & theParam) |
---|
| 364 | // Gives the kinetic energy of fission products |
---|
| 365 | { |
---|
| 366 | // Find maximal value of A for fragments |
---|
| 367 | G4double AfMax = std::max(Af1,Af2); |
---|
| 368 | if (AfMax < (A/2.0)) AfMax = A - AfMax; |
---|
| 369 | |
---|
| 370 | // Weights for symmetric and asymmetric components |
---|
| 371 | G4double Pas; |
---|
| 372 | if (theParam.GetW() > 1000) Pas = 0.0; |
---|
| 373 | else { |
---|
| 374 | G4double P1 = 0.5*std::exp(-0.5*(AfMax-theParam.GetA1())*(AfMax-theParam.GetA1())/ |
---|
| 375 | (theParam.GetSigma1()*theParam.GetSigma1())); |
---|
| 376 | |
---|
| 377 | G4double P2 = std::exp(-0.5*(AfMax-theParam.GetA2())*(AfMax-theParam.GetA2())/ |
---|
| 378 | (theParam.GetSigma2()*theParam.GetSigma2())); |
---|
| 379 | |
---|
| 380 | Pas = P1+P2; |
---|
| 381 | } |
---|
| 382 | |
---|
| 383 | |
---|
| 384 | G4double Ps; |
---|
| 385 | if (theParam.GetW() < 0.001) Ps = 0.0; |
---|
| 386 | else |
---|
| 387 | Ps = theParam.GetW()*std::exp(-0.5*(AfMax-theParam.GetAs())*(AfMax-theParam.GetAs())/ |
---|
| 388 | (theParam.GetSigmaS()*theParam.GetSigmaS())); |
---|
| 389 | |
---|
| 390 | |
---|
| 391 | |
---|
| 392 | G4double Psy = Ps/(Pas+Ps); |
---|
| 393 | |
---|
| 394 | |
---|
| 395 | // Fission fractions Xsy and Xas formed in symmetric and asymmetric modes |
---|
| 396 | G4double PPas = theParam.GetSigma1() + 2.0 * theParam.GetSigma2(); |
---|
| 397 | G4double PPsy = theParam.GetW() * theParam.GetSigmaS(); |
---|
| 398 | G4double Xas = PPas / (PPas+PPsy); |
---|
| 399 | G4double Xsy = PPsy / (PPas+PPsy); |
---|
| 400 | |
---|
| 401 | |
---|
| 402 | // Average kinetic energy for symmetric and asymmetric components |
---|
| 403 | G4double Eaverage = 0.1071*MeV*(Z*Z)/std::pow(A,1.0/3.0) + 22.2*MeV; |
---|
| 404 | |
---|
| 405 | |
---|
| 406 | // Compute maximal average kinetic energy of fragments and Energy Dispersion (sqrt) |
---|
| 407 | G4double TaverageAfMax; |
---|
| 408 | G4double ESigma; |
---|
| 409 | // Select randomly fission mode (symmetric or asymmetric) |
---|
| 410 | if (G4UniformRand() > Psy) { // Asymmetric Mode |
---|
| 411 | G4double A11 = theParam.GetA1()-0.7979*theParam.GetSigma1(); |
---|
| 412 | G4double A12 = theParam.GetA1()+0.7979*theParam.GetSigma1(); |
---|
| 413 | G4double A21 = theParam.GetA2()-0.7979*theParam.GetSigma2(); |
---|
| 414 | G4double A22 = theParam.GetA2()+0.7979*theParam.GetSigma2(); |
---|
| 415 | // scale factor |
---|
| 416 | G4double ScaleFactor = 0.5*theParam.GetSigma1()*(AsymmetricRatio(A,A11)+AsymmetricRatio(A,A12))+ |
---|
| 417 | theParam.GetSigma2()*(AsymmetricRatio(A,A21)+AsymmetricRatio(A,A22)); |
---|
| 418 | // Compute average kinetic energy for fragment with AfMax |
---|
| 419 | TaverageAfMax = (Eaverage + 12.5 * Xsy) * (PPas/ScaleFactor) * AsymmetricRatio(A,AfMax); |
---|
| 420 | ESigma = 10.0*MeV; // MeV |
---|
| 421 | |
---|
| 422 | } else { // Symmetric Mode |
---|
| 423 | G4double As0 = theParam.GetAs() + 0.7979*theParam.GetSigmaS(); |
---|
| 424 | // scale factor |
---|
| 425 | G4double ScaleFactor = theParam.GetW()*theParam.GetSigmaS()*SymmetricRatio(A,As0); |
---|
| 426 | // Compute average kinetic energy for fragment with AfMax |
---|
| 427 | TaverageAfMax = (Eaverage - 12.5*MeV*Xas) * (PPsy/ScaleFactor) * SymmetricRatio(A,AfMax); |
---|
| 428 | ESigma = 8.0*MeV; |
---|
| 429 | } |
---|
| 430 | |
---|
| 431 | |
---|
| 432 | // Select randomly, in accordance with Gaussian distribution, fragment kinetic energy |
---|
| 433 | G4double KineticEnergy; |
---|
| 434 | G4int i = 0; |
---|
| 435 | do { |
---|
| 436 | KineticEnergy = G4RandGauss::shoot(TaverageAfMax,ESigma); |
---|
| 437 | if (i++ > 100) return Eaverage; |
---|
| 438 | } while (KineticEnergy < Eaverage-3.72*ESigma || |
---|
| 439 | KineticEnergy > Eaverage+3.72*ESigma || |
---|
| 440 | KineticEnergy > Tmax); |
---|
| 441 | |
---|
| 442 | return KineticEnergy; |
---|
| 443 | } |
---|
| 444 | |
---|
| 445 | |
---|
| 446 | |
---|
| 447 | |
---|
| 448 | |
---|
| 449 | G4double G4CompetitiveFission::AsymmetricRatio(const G4double A,const G4double A11) |
---|
| 450 | { |
---|
| 451 | const G4double B1 = 23.5; |
---|
| 452 | const G4double A00 = 134.0; |
---|
| 453 | return Ratio(A,A11,B1,A00); |
---|
| 454 | } |
---|
| 455 | |
---|
| 456 | G4double G4CompetitiveFission::SymmetricRatio(const G4double A,const G4double A11) |
---|
| 457 | { |
---|
| 458 | const G4double B1 = 5.32; |
---|
| 459 | const G4double A00 = A/2.0; |
---|
| 460 | return Ratio(A,A11,B1,A00); |
---|
| 461 | } |
---|
| 462 | |
---|
| 463 | G4double G4CompetitiveFission::Ratio(const G4double A,const G4double A11, |
---|
| 464 | const G4double B1,const G4double A00) |
---|
| 465 | { |
---|
| 466 | if (A == 0) throw G4HadronicException(__FILE__, __LINE__, "G4CompetitiveFission::Ratio: A == 0!"); |
---|
| 467 | if (A11 >= A/2.0 && A11 <= (A00+10.0)) return 1.0-B1*((A11-A00)/A)*((A11-A00)/A); |
---|
| 468 | else return 1.0-B1*(10.0/A)*(10.0/A)-2.0*(10.0/A)*B1*((A11-A00-10.0)/A); |
---|
| 469 | } |
---|
| 470 | |
---|
| 471 | |
---|
| 472 | |
---|
| 473 | |
---|
| 474 | |
---|
| 475 | G4ThreeVector G4CompetitiveFission::IsotropicVector(const G4double Magnitude) |
---|
| 476 | // Samples a isotropic random vectorwith a magnitud given by Magnitude. |
---|
| 477 | // By default Magnitude = 1.0 |
---|
| 478 | { |
---|
| 479 | G4double CosTheta = 1.0 - 2.0*G4UniformRand(); |
---|
| 480 | G4double SinTheta = std::sqrt(1.0 - CosTheta*CosTheta); |
---|
| 481 | G4double Phi = twopi*G4UniformRand(); |
---|
| 482 | G4ThreeVector Vector(Magnitude*std::cos(Phi)*SinTheta, |
---|
| 483 | Magnitude*std::sin(Phi)*SinTheta, |
---|
| 484 | Magnitude*CosTheta); |
---|
| 485 | return Vector; |
---|
| 486 | } |
---|
| 487 | |
---|
| 488 | |
---|
| 489 | #ifdef debug |
---|
| 490 | void G4CompetitiveFission::CheckConservation(const G4Fragment & theInitialState, |
---|
| 491 | G4FragmentVector * Result) const |
---|
| 492 | { |
---|
| 493 | G4double ProductsEnergy =0; |
---|
| 494 | G4ThreeVector ProductsMomentum; |
---|
| 495 | G4int ProductsA = 0; |
---|
| 496 | G4int ProductsZ = 0; |
---|
| 497 | G4FragmentVector::iterator h; |
---|
| 498 | for (h = Result->begin(); h != Result->end(); h++) { |
---|
| 499 | G4LorentzVector tmp = (*h)->GetMomentum(); |
---|
| 500 | ProductsEnergy += tmp.e(); |
---|
| 501 | ProductsMomentum += tmp.vect(); |
---|
| 502 | ProductsA += static_cast<G4int>((*h)->GetA()); |
---|
| 503 | ProductsZ += static_cast<G4int>((*h)->GetZ()); |
---|
| 504 | } |
---|
| 505 | |
---|
| 506 | if (ProductsA != theInitialState.GetA()) { |
---|
| 507 | G4cout << "!!!!!!!!!! Baryonic Number Conservation Violation !!!!!!!!!!" << G4endl; |
---|
| 508 | G4cout << "G4CompetitiveFission.cc: Barionic Number Conservation test for fission fragments" |
---|
| 509 | << G4endl; |
---|
| 510 | G4cout << "Initial A = " << theInitialState.GetA() |
---|
| 511 | << " Fragments A = " << ProductsA << " Diference --> " |
---|
| 512 | << theInitialState.GetA() - ProductsA << G4endl; |
---|
| 513 | } |
---|
| 514 | if (ProductsZ != theInitialState.GetZ()) { |
---|
| 515 | G4cout << "!!!!!!!!!! Charge Conservation Violation !!!!!!!!!!" << G4endl; |
---|
| 516 | G4cout << "G4CompetitiveFission.cc: Charge Conservation test for fission fragments" |
---|
| 517 | << G4endl; |
---|
| 518 | G4cout << "Initial Z = " << theInitialState.GetZ() |
---|
| 519 | << " Fragments Z = " << ProductsZ << " Diference --> " |
---|
| 520 | << theInitialState.GetZ() - ProductsZ << G4endl; |
---|
| 521 | } |
---|
| 522 | if (std::abs(ProductsEnergy-theInitialState.GetMomentum().e()) > 1.0*keV) { |
---|
| 523 | G4cout << "!!!!!!!!!! Energy Conservation Violation !!!!!!!!!!" << G4endl; |
---|
| 524 | G4cout << "G4CompetitiveFission.cc: Energy Conservation test for fission fragments" |
---|
| 525 | << G4endl; |
---|
| 526 | G4cout << "Initial E = " << theInitialState.GetMomentum().e()/MeV << " MeV" |
---|
| 527 | << " Fragments E = " << ProductsEnergy/MeV << " MeV Diference --> " |
---|
| 528 | << (theInitialState.GetMomentum().e() - ProductsEnergy)/MeV << " MeV" << G4endl; |
---|
| 529 | } |
---|
| 530 | if (std::abs(ProductsMomentum.x()-theInitialState.GetMomentum().x()) > 1.0*keV || |
---|
| 531 | std::abs(ProductsMomentum.y()-theInitialState.GetMomentum().y()) > 1.0*keV || |
---|
| 532 | std::abs(ProductsMomentum.z()-theInitialState.GetMomentum().z()) > 1.0*keV) { |
---|
| 533 | G4cout << "!!!!!!!!!! Momentum Conservation Violation !!!!!!!!!!" << G4endl; |
---|
| 534 | G4cout << "G4CompetitiveFission.cc: Momentum Conservation test for fission fragments" |
---|
| 535 | << G4endl; |
---|
| 536 | G4cout << "Initial P = " << theInitialState.GetMomentum().vect() << " MeV" |
---|
| 537 | << " Fragments P = " << ProductsMomentum << " MeV Diference --> " |
---|
| 538 | << theInitialState.GetMomentum().vect() - ProductsMomentum << " MeV" << G4endl; |
---|
| 539 | } |
---|
| 540 | return; |
---|
| 541 | } |
---|
| 542 | #endif |
---|
| 543 | |
---|
| 544 | |
---|
| 545 | |
---|
| 546 | |
---|