// // ******************************************************************** // * License and Disclaimer * // * * // * The Geant4 software is copyright of the Copyright Holders of * // * the Geant4 Collaboration. It is provided under the terms and * // * conditions of the Geant4 Software License, included in the file * // * LICENSE and available at http://cern.ch/geant4/license . These * // * include a list of copyright holders. * // * * // * Neither the authors of this software system, nor their employing * // * institutes,nor the agencies providing financial support for this * // * work make any representation or warranty, express or implied, * // * regarding this software system or assume any liability for its * // * use. Please see the license in the file LICENSE and URL above * // * for the full disclaimer and the limitation of liability. * // * * // * This code implementation is the result of the scientific and * // * technical work of the GEANT4 collaboration. * // * By using, copying, modifying or distributing the software (or * // * any work based on the software) you agree to acknowledge its * // * use in resulting scientific publications, and indicate your * // * acceptance of all terms of the Geant4 Software license. * // ******************************************************************** // // // // Hadronic Process: Nuclear De-excitations // by V. Lara (Sept 2001) // // J. M. Quesada : several fixes in total GEM width // J. M. Quesada 14/07/2009 bug fixed in total emission width (hbarc) // J. M. Quesada (September 2009) several fixes: // -level density parameter of residual calculated at its right excitation energy. // -InitialLeveldensity calculated according to the right conditions of the // initial excited nucleus. #include "G4GEMProbability.hh" #include "G4PairingCorrection.hh" G4GEMProbability::G4GEMProbability(const G4GEMProbability &) : G4VEmissionProbability() { throw G4HadronicException(__FILE__, __LINE__, "G4GEMProbability::copy_constructor meant to not be accessable"); } const G4GEMProbability & G4GEMProbability:: operator=(const G4GEMProbability &) { throw G4HadronicException(__FILE__, __LINE__, "G4GEMProbability::operator= meant to not be accessable"); return *this; } G4bool G4GEMProbability::operator==(const G4GEMProbability &) const { return false; } G4bool G4GEMProbability::operator!=(const G4GEMProbability &) const { return true; } G4double G4GEMProbability::EmissionProbability(const G4Fragment & fragment, const G4double MaximalKineticEnergy) { G4double EmissionProbability = 0.0; if (MaximalKineticEnergy > 0.0 && fragment.GetExcitationEnergy() > 0.0) { G4double CoulombBarrier = GetCoulombBarrier(fragment); EmissionProbability = CalcProbability(fragment,MaximalKineticEnergy,CoulombBarrier); Normalization = EmissionProbability; // Next there is a loop over excited states for this channel summing probabilities if (ExcitationEnergies && ExcitationSpins && ExcitationLifetimes) { G4double SavedSpin = Spin; for (unsigned int i = 0; i < ExcitationEnergies->size(); i++) { Spin = ExcitationSpins->operator[](i); // substract excitation energies G4double Tmax = MaximalKineticEnergy - ExcitationEnergies->operator[](i); if (Tmax > 0.0) { G4double width = CalcProbability(fragment,Tmax,CoulombBarrier); // update probability if (hbar_Planck*std::log(2.0)/width < ExcitationLifetimes->operator[](i)) { EmissionProbability += width; } } } // Restore Spin Spin = SavedSpin; } } return EmissionProbability; } G4double G4GEMProbability::CalcProbability(const G4Fragment & fragment, const G4double MaximalKineticEnergy, const G4double V) // Calculate integrated probability (width) for evaporation channel { G4double ResidualA = static_cast(fragment.GetA() - theA); G4double ResidualZ = static_cast(fragment.GetZ() - theZ); G4double U = fragment.GetExcitationEnergy(); G4double NuclearMass = G4ParticleTable::GetParticleTable()-> GetIonTable()->GetNucleusMass(theZ,theA); G4double Alpha = CalcAlphaParam(fragment); G4double Beta = CalcBetaParam(fragment); // ***RESIDUAL*** //JMQ (September 2009) the following quantities refer to the RESIDUAL: G4double delta0 = G4PairingCorrection::GetInstance()->GetPairingCorrection( static_cast( ResidualA ) , static_cast( ResidualZ ) ); G4double a = theEvapLDPptr->LevelDensityParameter(static_cast(ResidualA), static_cast(ResidualZ),MaximalKineticEnergy+V-delta0); G4double Ux = (2.5 + 150.0/ResidualA)*MeV; G4double Ex = Ux + delta0; G4double T = 1.0/(std::sqrt(a/Ux) - 1.5/Ux); //JMQ fixed bug in units G4double E0 = Ex - T*(std::log(T/MeV) - std::log(a*MeV)/4.0 - 1.25*std::log(Ux/MeV) + 2.0*std::sqrt(a*Ux)); // ***end RESIDUAL *** // ***PARENT*** //JMQ (September 2009) the following quantities refer to the PARENT: G4double deltaCN=G4PairingCorrection::GetInstance()-> GetPairingCorrection(static_cast(fragment.GetA()),static_cast(fragment.GetZ())); G4double aCN = theEvapLDPptr->LevelDensityParameter(static_cast(fragment.GetA()), static_cast(fragment.GetZ()),U-deltaCN); G4double UxCN = (2.5 + 150.0/fragment.GetA())*MeV; G4double ExCN = UxCN + deltaCN; G4double TCN = 1.0/(std::sqrt(aCN/UxCN) - 1.5/UxCN); //JMQ fixed bug in units G4double E0CN = ExCN - TCN*(std::log(TCN/MeV) - std::log(aCN*MeV)/4.0 - 1.25*std::log(UxCN/MeV) + 2.0*std::sqrt(aCN*UxCN)); // ***end PARENT*** G4double Width; G4double InitialLevelDensity; G4double t = MaximalKineticEnergy/T; if ( MaximalKineticEnergy < Ex ) { //JMQ 190709 bug in I1 fixed (T was missing) Width = (I1(t,t)*T + (Beta+V)*I0(t))/std::exp(E0/T); //JMQ 160909 fix: InitialLevelDensity has been taken away (different conditions for initial CN..) } else { G4double tx = Ex/T; G4double s = 2.0*std::sqrt(a*(MaximalKineticEnergy-delta0)); G4double sx = 2.0*std::sqrt(a*(Ex-delta0)); Width = I1(t,tx)*T/std::exp(E0/T) + I3(s,sx)*std::exp(s)/(std::sqrt(2.0)*a); // For charged particles (Beta+V) = 0 beacuse Beta = -V if (theZ == 0) { Width += (Beta+V)*(I0(tx)/std::exp(E0/T) + 2.0*std::sqrt(2.0)*I2(s,sx)*std::exp(s)); } } //JMQ 14/07/2009 BIG BUG : NuclearMass is in MeV => hbarc instead of hbar_planck must be used // G4double g = (2.0*Spin+1.0)*NuclearMass/(pi2* hbar_Planck*hbar_Planck); G4double g = (2.0*Spin+1.0)*NuclearMass/(pi2* hbarc*hbarc); //JMQ 190709 fix on Rb and geometrical cross sections according to Furihata's paper // (JAERI-Data/Code 2001-105, p6) // G4double RN = 0.0; G4double Rb = 0.0; if (theA > 4) { // G4double R1 = std::pow(ResidualA,1.0/3.0); // G4double R2 = std::pow(G4double(theA),1.0/3.0); G4double Ad = std::pow(ResidualA,1.0/3.0); G4double Aj = std::pow(G4double(theA),1.0/3.0); // RN = 1.12*(R1 + R2) - 0.86*((R1+R2)/(R1*R2)); Rb = 1.12*(Aj + Ad) - 0.86*((Aj+Ad)/(Aj*Ad))+2.85; Rb *= fermi; } else if (theA>1) { G4double Ad = std::pow(ResidualA,1.0/3.0); G4double Aj = std::pow(G4double(theA),1.0/3.0); Rb=1.5*(Aj+Ad)*fermi; } else { G4double Ad = std::pow(ResidualA,1.0/3.0); Rb = 1.5*Ad*fermi; } // G4double GeometricalXS = pi*RN*RN*std::pow(ResidualA,2./3.); G4double GeometricalXS = pi*Rb*Rb; //end of JMQ fix on Rb by 190709 //JMQ 160909 fix: initial level density must be calculated according to the // conditions at the initial compound nucleus // (it has been removed from previous "if" for the residual) if ( U < ExCN ) { InitialLevelDensity = (pi/12.0)*std::exp((U-E0CN)/TCN)/TCN; } else { InitialLevelDensity = (pi/12.0)*std::exp(2*std::sqrt(aCN*(U-deltaCN)))/std::pow(aCN*std::pow(U-deltaCN,5.0),1.0/4.0); } // //JMQ 190709 BUG : pi instead of sqrt(pi) must be here according to Furihata's report: // Width *= std::sqrt(pi)*g*GeometricalXS*Alpha/(12.0*InitialLevelDensity); Width *= pi*g*GeometricalXS*Alpha/(12.0*InitialLevelDensity); return Width; } G4double G4GEMProbability::I0(const G4double t) { G4double result = (std::exp(t) - 1.0); return result; } G4double G4GEMProbability::I1(const G4double t, const G4double tx) { G4double result = t - tx + 1.0; result *= std::exp(tx); result -= (t + 1.0); return result; } G4double G4GEMProbability::I2(const G4double s, const G4double sx) { G4double S = 1.0/std::sqrt(s); G4double Sx = 1.0/std::sqrt(sx); G4double p1 = S*S*S*( 1.0 + S*S*( 1.5 + 3.75*S*S) ); G4double p2 = Sx*Sx*Sx*( 1.0 + Sx*Sx*( 1.5 + 3.75*Sx*Sx) )*std::exp(sx-s); return p1-p2; } G4double G4GEMProbability::I3(const G4double s, const G4double sx) { G4double s2 = s*s; G4double sx2 = sx*sx; G4double S = 1.0/std::sqrt(s); G4double S2 = S*S; G4double Sx = 1.0/std::sqrt(sx); G4double Sx2 = Sx*Sx; G4double p1 = S *(2.0 + S2 *( 4.0 + S2 *( 13.5 + S2 *( 60.0 + S2 * 325.125 )))); G4double p2 = Sx*Sx2 *( (s2-sx2) + Sx2 *( (1.5*s2+0.5*sx2) + Sx2 *( (3.75*s2+0.25*sx2) + Sx2 *( (12.875*s2+0.625*sx2) + Sx2 *( (59.0625*s2+0.9375*sx2) + Sx2 *(324.8*s2+3.28*sx2)))))); p2 *= std::exp(sx-s); return p1-p2; }