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Geant4/processes/electromagnetic/standard/src/G4BetheHeitlerModel.cc

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Differences between /processes/electromagnetic/standard/src/G4BetheHeitlerModel.cc (Version 11.3.0) and /processes/electromagnetic/standard/src/G4BetheHeitlerModel.cc (Version 10.7.p3)


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 25 //                                                 25 //
 26 //                                                 26 //
 27 // -------------------------------------------     27 // -------------------------------------------------------------------
 28 //                                                 28 //
 29 // GEANT4 Class file                               29 // GEANT4 Class file
 30 //                                                 30 //
 31 //                                                 31 //
 32 // File name:     G4BetheHeitlerModel              32 // File name:     G4BetheHeitlerModel
 33 //                                                 33 //
 34 // Author:        Vladimir Ivanchenko on base      34 // Author:        Vladimir Ivanchenko on base of Michel Maire code
 35 //                                                 35 //
 36 // Creation date: 15.03.2005                       36 // Creation date: 15.03.2005
 37 //                                                 37 //
 38 // Modifications by Vladimir Ivanchenko, Miche     38 // Modifications by Vladimir Ivanchenko, Michel Maire, Mihaly Novak
 39 //                                                 39 //
 40 // Class Description:                              40 // Class Description:
 41 //                                                 41 //
 42 // -------------------------------------------     42 // -------------------------------------------------------------------
 43 //                                                 43 //
 44                                                    44 
 45 #include "G4BetheHeitlerModel.hh"                  45 #include "G4BetheHeitlerModel.hh"
 46 #include "G4PhysicalConstants.hh"                  46 #include "G4PhysicalConstants.hh"
 47 #include "G4SystemOfUnits.hh"                      47 #include "G4SystemOfUnits.hh"
 48 #include "G4Electron.hh"                           48 #include "G4Electron.hh"
 49 #include "G4Positron.hh"                           49 #include "G4Positron.hh"
 50 #include "G4Gamma.hh"                              50 #include "G4Gamma.hh"
 51 #include "Randomize.hh"                            51 #include "Randomize.hh"
 52 #include "G4ParticleChangeForGamma.hh"             52 #include "G4ParticleChangeForGamma.hh"
 53 #include "G4Pow.hh"                                53 #include "G4Pow.hh"
 54 #include "G4Exp.hh"                                54 #include "G4Exp.hh"
 55 #include "G4ModifiedTsai.hh"                       55 #include "G4ModifiedTsai.hh"
 56 #include "G4EmParameters.hh"                   << 
 57 #include "G4EmElementXS.hh"                    << 
 58 #include "G4AutoLock.hh"                       << 
 59                                                    56 
 60 const G4int G4BetheHeitlerModel::gMaxZet = 120     57 const G4int G4BetheHeitlerModel::gMaxZet = 120; 
 61 std::vector<G4BetheHeitlerModel::ElementData*>     58 std::vector<G4BetheHeitlerModel::ElementData*> G4BetheHeitlerModel::gElementData;
 62                                                    59 
 63 namespace                                      << 
 64 {                                              << 
 65   G4Mutex theBetheHMutex = G4MUTEX_INITIALIZER << 
 66 }                                              << 
 67                                                << 
 68 G4BetheHeitlerModel::G4BetheHeitlerModel(const     60 G4BetheHeitlerModel::G4BetheHeitlerModel(const G4ParticleDefinition*, 
 69                                          const     61                                          const G4String& nam)
 70 : G4VEmModel(nam),                                 62 : G4VEmModel(nam), 
 71   fG4Calc(G4Pow::GetInstance()), fTheGamma(G4G     63   fG4Calc(G4Pow::GetInstance()), fTheGamma(G4Gamma::Gamma()),
 72   fTheElectron(G4Electron::Electron()), fThePo     64   fTheElectron(G4Electron::Electron()), fThePositron(G4Positron::Positron()),
 73   fParticleChange(nullptr)                         65   fParticleChange(nullptr) 
 74 {                                                  66 {
 75   SetAngularDistribution(new G4ModifiedTsai())     67   SetAngularDistribution(new G4ModifiedTsai());
 76 }                                                  68 }
 77                                                    69 
 78 G4BetheHeitlerModel::~G4BetheHeitlerModel()        70 G4BetheHeitlerModel::~G4BetheHeitlerModel()
 79 {                                                  71 {
 80   if (isFirstInstance) {                       <<  72   if (IsMaster()) {
 81     for (auto const & ptr : gElementData) { de <<  73     // clear ElementData container
                                                   >>  74     for (size_t iz = 0; iz < gElementData.size(); ++iz) {
                                                   >>  75       if (gElementData[iz]) delete gElementData[iz];
                                                   >>  76     }
 82     gElementData.clear();                          77     gElementData.clear(); 
 83   }                                                78   }
 84   delete fXSection;                            << 
 85 }                                                  79 }
 86                                                    80 
 87 void G4BetheHeitlerModel::Initialise(const G4P     81 void G4BetheHeitlerModel::Initialise(const G4ParticleDefinition* p, 
 88                                      const G4D     82                                      const G4DataVector& cuts)
 89 {                                                  83 {
 90   if (!fParticleChange) { fParticleChange = Ge <<  84   if (IsMaster()) {
 91                                                << 
 92   if (isFirstInstance || gElementData.empty()) << 
 93     G4AutoLock l(&theBetheHMutex);             << 
 94     if (gElementData.empty()) {                << 
 95       isFirstInstance = true;                  << 
 96       gElementData.resize(gMaxZet+1, nullptr); << 
 97                                                << 
 98       // EPICS2017 flag should be checked only << 
 99       useEPICS2017 = G4EmParameters::Instance( << 
100       if (useEPICS2017) {                      << 
101   fXSection = new G4EmElementXS(1, 100, "convE << 
102       }                                        << 
103     }                                          << 
104     // static data should be initialised only  << 
105     InitialiseElementData();                       85     InitialiseElementData();
106     l.unlock();                                << 
107   }                                                86   }
108   // element selectors should be initialised i <<  87   if (!fParticleChange) { fParticleChange = GetParticleChangeForGamma(); }
109   if(IsMaster()) {                             <<  88   if (IsMaster()) { 
110     InitialiseElementSelectors(p, cuts);           89     InitialiseElementSelectors(p, cuts); 
111   }                                                90   }
112 }                                                  91 }
113                                                    92 
114 void G4BetheHeitlerModel::InitialiseLocal(cons     93 void G4BetheHeitlerModel::InitialiseLocal(const G4ParticleDefinition*, 
115                                           G4VE     94                                           G4VEmModel* masterModel)
116 {                                                  95 {
117   SetElementSelectors(masterModel->GetElementS     96   SetElementSelectors(masterModel->GetElementSelectors());
118 }                                                  97 }
119                                                    98 
120 // Calculates the microscopic cross section in     99 // Calculates the microscopic cross section in GEANT4 internal units.
121 // A parametrized formula from L. Urban is use    100 // A parametrized formula from L. Urban is used to estimate
122 // the total cross section.                       101 // the total cross section.
123 // It gives a good description of the data fro    102 // It gives a good description of the data from 1.5 MeV to 100 GeV.
124 // below 1.5 MeV: sigma=sigma(1.5MeV)*(GammaEn    103 // below 1.5 MeV: sigma=sigma(1.5MeV)*(GammaEnergy-2electronmass)
125 //                                   *(GammaEn    104 //                                   *(GammaEnergy-2electronmass) 
126 G4double                                          105 G4double 
127 G4BetheHeitlerModel::ComputeCrossSectionPerAto    106 G4BetheHeitlerModel::ComputeCrossSectionPerAtom(const G4ParticleDefinition*, 
128                                                   107                                                 G4double gammaEnergy, G4double Z, 
129                                                   108                                                 G4double, G4double, G4double)
130 {                                                 109 {
131   G4double xSection = 0.0 ;                       110   G4double xSection = 0.0 ;
132   // short versions                               111   // short versions
133   static const G4double kMC2  = CLHEP::electro    112   static const G4double kMC2  = CLHEP::electron_mass_c2;
134   // zero cross section below the kinematical     113   // zero cross section below the kinematical limit: Eg<2mc^2
135   if (Z < 0.9 || gammaEnergy <= 2.0*kMC2) { re    114   if (Z < 0.9 || gammaEnergy <= 2.0*kMC2) { return xSection; }
136                                                << 
137   G4int iZ = G4lrint(Z);                       << 
138   if (useEPICS2017 && iZ < 101) {              << 
139     return fXSection->GetXS(iZ, gammaEnergy);  << 
140   }                                            << 
141                                                << 
142   //                                              115   //
143   static const G4double gammaEnergyLimit = 1.5    116   static const G4double gammaEnergyLimit = 1.5*CLHEP::MeV;
144   // set coefficients a, b c                      117   // set coefficients a, b c
145   static const G4double a0 =  8.7842e+2*CLHEP:    118   static const G4double a0 =  8.7842e+2*CLHEP::microbarn;
146   static const G4double a1 = -1.9625e+3*CLHEP:    119   static const G4double a1 = -1.9625e+3*CLHEP::microbarn; 
147   static const G4double a2 =  1.2949e+3*CLHEP:    120   static const G4double a2 =  1.2949e+3*CLHEP::microbarn;
148   static const G4double a3 = -2.0028e+2*CLHEP:    121   static const G4double a3 = -2.0028e+2*CLHEP::microbarn; 
149   static const G4double a4 =  1.2575e+1*CLHEP:    122   static const G4double a4 =  1.2575e+1*CLHEP::microbarn; 
150   static const G4double a5 = -2.8333e-1*CLHEP:    123   static const G4double a5 = -2.8333e-1*CLHEP::microbarn;
151                                                   124   
152   static const G4double b0 = -1.0342e+1*CLHEP:    125   static const G4double b0 = -1.0342e+1*CLHEP::microbarn;
153   static const G4double b1 =  1.7692e+1*CLHEP:    126   static const G4double b1 =  1.7692e+1*CLHEP::microbarn;
154   static const G4double b2 = -8.2381   *CLHEP:    127   static const G4double b2 = -8.2381   *CLHEP::microbarn;
155   static const G4double b3 =  1.3063   *CLHEP:    128   static const G4double b3 =  1.3063   *CLHEP::microbarn;
156   static const G4double b4 = -9.0815e-2*CLHEP:    129   static const G4double b4 = -9.0815e-2*CLHEP::microbarn;
157   static const G4double b5 =  2.3586e-3*CLHEP:    130   static const G4double b5 =  2.3586e-3*CLHEP::microbarn;
158                                                   131   
159   static const G4double c0 = -4.5263e+2*CLHEP:    132   static const G4double c0 = -4.5263e+2*CLHEP::microbarn;
160   static const G4double c1 =  1.1161e+3*CLHEP:    133   static const G4double c1 =  1.1161e+3*CLHEP::microbarn; 
161   static const G4double c2 = -8.6749e+2*CLHEP:    134   static const G4double c2 = -8.6749e+2*CLHEP::microbarn;
162   static const G4double c3 =  2.1773e+2*CLHEP:    135   static const G4double c3 =  2.1773e+2*CLHEP::microbarn; 
163   static const G4double c4 = -2.0467e+1*CLHEP:    136   static const G4double c4 = -2.0467e+1*CLHEP::microbarn;
164   static const G4double c5 =  6.5372e-1*CLHEP:    137   static const G4double c5 =  6.5372e-1*CLHEP::microbarn;
165   // check low energy limit of the approximati    138   // check low energy limit of the approximation (1.5 MeV)
166   G4double gammaEnergyOrg = gammaEnergy;          139   G4double gammaEnergyOrg = gammaEnergy;
167   if (gammaEnergy < gammaEnergyLimit) { gammaE    140   if (gammaEnergy < gammaEnergyLimit) { gammaEnergy = gammaEnergyLimit; }
168   // compute gamma energy variables               141   // compute gamma energy variables
169   const G4double x  = G4Log(gammaEnergy/kMC2);    142   const G4double x  = G4Log(gammaEnergy/kMC2);
170   const G4double x2 = x *x;                       143   const G4double x2 = x *x; 
171   const G4double x3 = x2*x;                       144   const G4double x3 = x2*x;
172   const G4double x4 = x3*x;                       145   const G4double x4 = x3*x;
173   const G4double x5 = x4*x;                       146   const G4double x5 = x4*x;
174   //                                              147   //
175   const G4double F1 = a0 + a1*x + a2*x2 + a3*x    148   const G4double F1 = a0 + a1*x + a2*x2 + a3*x3 + a4*x4 + a5*x5;
176   const G4double F2 = b0 + b1*x + b2*x2 + b3*x    149   const G4double F2 = b0 + b1*x + b2*x2 + b3*x3 + b4*x4 + b5*x5;
177   const G4double F3 = c0 + c1*x + c2*x2 + c3*x    150   const G4double F3 = c0 + c1*x + c2*x2 + c3*x3 + c4*x4 + c5*x5;     
178   // compute the approximated cross section       151   // compute the approximated cross section 
179   xSection = (Z + 1.)*(F1*Z + F2*Z*Z + F3);       152   xSection = (Z + 1.)*(F1*Z + F2*Z*Z + F3);
180   // check if we are below the limit of the ap    153   // check if we are below the limit of the approximation and apply correction
181   if (gammaEnergyOrg < gammaEnergyLimit) {        154   if (gammaEnergyOrg < gammaEnergyLimit) {
182     const G4double dum = (gammaEnergyOrg-2.*kM    155     const G4double dum = (gammaEnergyOrg-2.*kMC2)/(gammaEnergyLimit-2.*kMC2);
183     xSection *= dum*dum;                          156     xSection *= dum*dum;
184   }                                               157   }
185   // make sure that the cross section is never    158   // make sure that the cross section is never negative
186   xSection = std::max(xSection, 0.);              159   xSection = std::max(xSection, 0.); 
187   return xSection;                                160   return xSection;
188 }                                                 161 }
189                                                   162 
190 // The secondaries e+e- energies are sampled u    163 // The secondaries e+e- energies are sampled using the Bethe - Heitler
191 // cross sections with Coulomb correction.        164 // cross sections with Coulomb correction.
192 // A modified version of the random number tec    165 // A modified version of the random number techniques of Butcher & Messel
193 // is used (Nuc Phys 20(1960),15).                166 // is used (Nuc Phys 20(1960),15).
194 //                                                167 //
195 // GEANT4 internal units.                         168 // GEANT4 internal units.
196 //                                                169 //
197 // Note 1 : Effects due to the breakdown of th    170 // Note 1 : Effects due to the breakdown of the Born approximation at
198 //          low energy are ignored.               171 //          low energy are ignored.
199 // Note 2 : The differential cross section imp    172 // Note 2 : The differential cross section implicitly takes account of 
200 //          pair creation in both nuclear and     173 //          pair creation in both nuclear and atomic electron fields.
201 //          However triplet prodution is not g    174 //          However triplet prodution is not generated.
202 void G4BetheHeitlerModel::SampleSecondaries(st    175 void G4BetheHeitlerModel::SampleSecondaries(std::vector<G4DynamicParticle*>* fvect,
203                                             co    176                                             const G4MaterialCutsCouple* couple,
204                                             co    177                                             const G4DynamicParticle* aDynamicGamma,
205                                             G4    178                                             G4double, G4double)
206 {                                                 179 {
207   // set some constant values                     180   // set some constant values
208   const G4double    gammaEnergy = aDynamicGamm    181   const G4double    gammaEnergy = aDynamicGamma->GetKineticEnergy();
209   const G4double    eps0        = CLHEP::elect    182   const G4double    eps0        = CLHEP::electron_mass_c2/gammaEnergy;
210   //                                              183   //
211   // check kinematical limit: gamma energy(Eg)    184   // check kinematical limit: gamma energy(Eg) must be at least 2 e- rest mass
212   if (eps0 > 0.5) { return; }                     185   if (eps0 > 0.5) { return; }
213   //                                              186   //
214   // select target element of the material (pr    187   // select target element of the material (probs. are based on partial x-secs)
215   const G4Element* anElement = SelectTargetAto    188   const G4Element* anElement = SelectTargetAtom(couple, fTheGamma, gammaEnergy,
216                                           aDyn    189                                           aDynamicGamma->GetLogKineticEnergy());
217                                                   190 
218   //                                              191   // 
219   // get the random engine                        192   // get the random engine
220   CLHEP::HepRandomEngine* rndmEngine = G4Rando    193   CLHEP::HepRandomEngine* rndmEngine = G4Random::getTheEngine();
221   //                                              194   //
222   // 'eps' is the total energy transferred to     195   // 'eps' is the total energy transferred to one of the e-/e+ pair in initial
223   // gamma energy units Eg. Since the correspo    196   // gamma energy units Eg. Since the corresponding DCS is symmetric on eps=0.5,
224   // the kinematical limits for eps0=mc^2/Eg <    197   // the kinematical limits for eps0=mc^2/Eg <= eps <= 0.5 
225   // 1. 'eps' is sampled uniformly on the [eps    198   // 1. 'eps' is sampled uniformly on the [eps0, 0.5] inteval if Eg<Egsmall 
226   // 2. otherwise, on the [eps_min, 0.5] inter    199   // 2. otherwise, on the [eps_min, 0.5] interval according to the DCS (case 2.) 
227   G4double eps;                                   200   G4double eps;
228   // case 1.                                      201   // case 1.
229   static const G4double Egsmall = 2.*CLHEP::Me    202   static const G4double Egsmall = 2.*CLHEP::MeV;
230   if (gammaEnergy < Egsmall) {                    203   if (gammaEnergy < Egsmall) {
231     eps = eps0 + (0.5-eps0)*rndmEngine->flat()    204     eps = eps0 + (0.5-eps0)*rndmEngine->flat();
232   } else {                                        205   } else {
233   // case 2.                                      206   // case 2.
234     // get the Coulomb factor for the target e    207     // get the Coulomb factor for the target element (Z) and gamma energy (Eg)
235     // F(Z) = 8*ln(Z)/3           if Eg <= 50     208     // F(Z) = 8*ln(Z)/3           if Eg <= 50 [MeV] => no Coulomb correction
236     // F(Z) = 8*ln(Z)/3 + 8*fc(Z) if Eg  > 50     209     // F(Z) = 8*ln(Z)/3 + 8*fc(Z) if Eg  > 50 [MeV] => fc(Z) is the Coulomb cor.
237     //                                            210     //
238     // The screening variable 'delta(eps)' = 1    211     // The screening variable 'delta(eps)' = 136*Z^{-1/3}*eps0/[eps(1-eps)]
239     // Due to the Coulomb correction, the DCS     212     // Due to the Coulomb correction, the DCS can go below zero even at 
240     // kinematicaly allowed eps > eps0 values.    213     // kinematicaly allowed eps > eps0 values. In order to exclude this eps 
241     // range with negative DCS, the minimum ep    214     // range with negative DCS, the minimum eps value will be set to eps_min = 
242     // max[eps0, epsp] with epsp is the soluti    215     // max[eps0, epsp] with epsp is the solution of SF(delta(epsp)) - F(Z)/2 = 0 
243     // with SF being the screening function (S    216     // with SF being the screening function (SF1=SF2 at high value of delta). 
244     // The solution is epsp = 0.5 - 0.5*sqrt[     217     // The solution is epsp = 0.5 - 0.5*sqrt[ 1 - 4*136*Z^{-1/3}eps0/deltap] 
245     // with deltap = Exp[(42.038-F(Z))/8.29]-0    218     // with deltap = Exp[(42.038-F(Z))/8.29]-0.958. So the limits are:
246     // - when eps=eps_max = 0.5            =>     219     // - when eps=eps_max = 0.5            => delta_min = 136*Z^{-1/3}*eps0/4
247     // - epsp = 0.5 - 0.5*sqrt[ 1 - delta_min/    220     // - epsp = 0.5 - 0.5*sqrt[ 1 - delta_min/deltap]
248     // - and eps_min = max[eps0, epsp]            221     // - and eps_min = max[eps0, epsp]  
249     static const G4double midEnergy = 50.*CLHE    222     static const G4double midEnergy = 50.*CLHEP::MeV;
250     const  G4int           iZet = std::min(gMa    223     const  G4int           iZet = std::min(gMaxZet, anElement->GetZasInt());   
251     const  G4double deltaFactor = 136.*eps0/an    224     const  G4double deltaFactor = 136.*eps0/anElement->GetIonisation()->GetZ3();
252     G4double           deltaMax = gElementData    225     G4double           deltaMax = gElementData[iZet]->fDeltaMaxLow;
253     G4double                 FZ = 8.*anElement    226     G4double                 FZ = 8.*anElement->GetIonisation()->GetlogZ3();
254     if (gammaEnergy > midEnergy) {                227     if (gammaEnergy > midEnergy) { 
255       FZ      += 8.*(anElement->GetfCoulomb())    228       FZ      += 8.*(anElement->GetfCoulomb()); 
256       deltaMax = gElementData[iZet]->fDeltaMax    229       deltaMax = gElementData[iZet]->fDeltaMaxHigh;
257     }                                             230     }
258     const G4double deltaMin = 4.*deltaFactor;     231     const G4double deltaMin = 4.*deltaFactor; 
259     //                                            232     // 
260     // compute the limits of eps                  233     // compute the limits of eps
261     const G4double epsp     = 0.5 - 0.5*std::s    234     const G4double epsp     = 0.5 - 0.5*std::sqrt(1. - deltaMin/deltaMax) ;
262     const G4double epsMin   = std::max(eps0,ep    235     const G4double epsMin   = std::max(eps0,epsp);
263     const G4double epsRange = 0.5 - epsMin;       236     const G4double epsRange = 0.5 - epsMin;
264     //                                            237     //
265     // sample the energy rate (eps) of the cre    238     // sample the energy rate (eps) of the created electron (or positron)
266     G4double F10, F20;                            239     G4double F10, F20;
267     ScreenFunction12(deltaMin, F10, F20);         240     ScreenFunction12(deltaMin, F10, F20); 
268     F10 -= FZ;                                    241     F10 -= FZ;
269     F20 -= FZ;                                    242     F20 -= FZ; 
270     const G4double NormF1   = std::max(F10 * e    243     const G4double NormF1   = std::max(F10 * epsRange * epsRange, 0.); 
271     const G4double NormF2   = std::max(1.5 * F    244     const G4double NormF2   = std::max(1.5 * F20                , 0.);
272     const G4double NormCond = NormF1/(NormF1 +    245     const G4double NormCond = NormF1/(NormF1 + NormF2); 
273     // we will need 3 uniform random number fo    246     // we will need 3 uniform random number for each trial of sampling 
274     G4double rndmv[3];                            247     G4double rndmv[3];
275     G4double greject = 0.;                        248     G4double greject = 0.;
276     do {                                          249     do {
277       rndmEngine->flatArray(3, rndmv);            250       rndmEngine->flatArray(3, rndmv);
278       if (NormCond > rndmv[0]) {                  251       if (NormCond > rndmv[0]) {
279         eps = 0.5 - epsRange * fG4Calc->A13(rn    252         eps = 0.5 - epsRange * fG4Calc->A13(rndmv[1]);
280         const G4double delta = deltaFactor/(ep    253         const G4double delta = deltaFactor/(eps*(1.-eps));
281         greject = (ScreenFunction1(delta)-FZ)/    254         greject = (ScreenFunction1(delta)-FZ)/F10;
282       } else {                                    255       } else { 
283         eps = epsMin + epsRange*rndmv[1];         256         eps = epsMin + epsRange*rndmv[1];
284         const G4double delta = deltaFactor/(ep    257         const G4double delta = deltaFactor/(eps*(1.-eps));
285         greject = (ScreenFunction2(delta)-FZ)/    258         greject = (ScreenFunction2(delta)-FZ)/F20;
286       }                                           259       }
287       // Loop checking, 03-Aug-2015, Vladimir     260       // Loop checking, 03-Aug-2015, Vladimir Ivanchenko
288     } while (greject < rndmv[2]);                 261     } while (greject < rndmv[2]);
289   } //  end of eps sampling                       262   } //  end of eps sampling
290   //                                              263   //
291   // select charges randomly                      264   // select charges randomly
292   G4double eTotEnergy, pTotEnergy;                265   G4double eTotEnergy, pTotEnergy;
293   if (rndmEngine->flat() > 0.5) {                 266   if (rndmEngine->flat() > 0.5) {
294     eTotEnergy = (1.-eps)*gammaEnergy;            267     eTotEnergy = (1.-eps)*gammaEnergy;
295     pTotEnergy = eps*gammaEnergy;                 268     pTotEnergy = eps*gammaEnergy; 
296   } else {                                        269   } else {
297     pTotEnergy = (1.-eps)*gammaEnergy;            270     pTotEnergy = (1.-eps)*gammaEnergy;
298     eTotEnergy = eps*gammaEnergy;                 271     eTotEnergy = eps*gammaEnergy;
299   }                                               272   }
300   //                                              273   //
301   // sample pair kinematics                       274   // sample pair kinematics
302   const G4double eKinEnergy = std::max(0.,eTot    275   const G4double eKinEnergy = std::max(0.,eTotEnergy - CLHEP::electron_mass_c2);
303   const G4double pKinEnergy = std::max(0.,pTot    276   const G4double pKinEnergy = std::max(0.,pTotEnergy - CLHEP::electron_mass_c2);
304   //                                              277   //
305   G4ThreeVector eDirection, pDirection;           278   G4ThreeVector eDirection, pDirection;
306   //                                              279   //
307   GetAngularDistribution()->SamplePairDirectio    280   GetAngularDistribution()->SamplePairDirections(aDynamicGamma, 
308                                                   281                                                  eKinEnergy, pKinEnergy,
309                                                   282                                                  eDirection, pDirection);
310   // create G4DynamicParticle object for the p    283   // create G4DynamicParticle object for the particle1
311   auto aParticle1= new G4DynamicParticle(fTheE << 284   G4DynamicParticle* aParticle1= new G4DynamicParticle(
                                                   >> 285                      fTheElectron,eDirection,eKinEnergy);
312   // create G4DynamicParticle object for the p    286   // create G4DynamicParticle object for the particle2
313   auto aParticle2= new G4DynamicParticle(fTheP << 287   G4DynamicParticle* aParticle2= new G4DynamicParticle(
                                                   >> 288                      fThePositron,pDirection,pKinEnergy);
314   // Fill output vector                           289   // Fill output vector
315   fvect->push_back(aParticle1);                   290   fvect->push_back(aParticle1);
316   fvect->push_back(aParticle2);                   291   fvect->push_back(aParticle2);
317   // kill incident photon                         292   // kill incident photon
318   fParticleChange->SetProposedKineticEnergy(0.    293   fParticleChange->SetProposedKineticEnergy(0.);
319   fParticleChange->ProposeTrackStatus(fStopAnd    294   fParticleChange->ProposeTrackStatus(fStopAndKill);   
320 }                                                 295 }
321                                                   296 
322 // should be called only by the master and at     297 // should be called only by the master and at initialisation
323 void G4BetheHeitlerModel::InitialiseElementDat    298 void G4BetheHeitlerModel::InitialiseElementData() 
324 {                                                 299 {
                                                   >> 300   G4int size = gElementData.size();
                                                   >> 301   if (size < gMaxZet+1) {
                                                   >> 302     gElementData.resize(gMaxZet+1, nullptr);
                                                   >> 303   }
325   // create for all elements that are in the d    304   // create for all elements that are in the detector
326   auto elemTable = G4Element::GetElementTable( << 305   const G4ElementTable* elemTable = G4Element::GetElementTable();
327   for (auto const & elem : *elemTable) {       << 306   size_t numElems = (*elemTable).size();
328     const G4int Z = elem->GetZasInt();         << 307   for (size_t ie = 0; ie < numElems; ++ie) {
329     const G4int iz = std::min(gMaxZet, Z);     << 308     const G4Element* elem = (*elemTable)[ie];
330     if (nullptr == gElementData[iz]) { // crea << 309     const G4int        iz = std::min(gMaxZet, elem->GetZasInt());
                                                   >> 310     if (!gElementData[iz]) { // create it if doesn't exist yet
331       G4double FZLow     = 8.*elem->GetIonisat    311       G4double FZLow     = 8.*elem->GetIonisation()->GetlogZ3();
332       G4double FZHigh    = FZLow + 8.*elem->Ge    312       G4double FZHigh    = FZLow + 8.*elem->GetfCoulomb();
333       auto elD           = new ElementData();  << 313       ElementData* elD   = new ElementData(); 
334       elD->fDeltaMaxLow  = G4Exp((42.038 - FZL    314       elD->fDeltaMaxLow  = G4Exp((42.038 - FZLow )/8.29) - 0.958;
335       elD->fDeltaMaxHigh = G4Exp((42.038 - FZH    315       elD->fDeltaMaxHigh = G4Exp((42.038 - FZHigh)/8.29) - 0.958;
336       gElementData[iz]   = elD;                   316       gElementData[iz]   = elD;
337     }                                             317     }
338     if (useEPICS2017 && Z < 101) {             << 
339       fXSection->Retrieve(Z);                  << 
340     }                                          << 
341   }                                               318   }
342                                                << 
343 }                                                 319 }
344                                                   320 
345                                                   321