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25 // 25 //
>> 26 // $Id: G4BetheHeitlerModel.cc,v 1.9 2006/06/29 19:52:40 gunter Exp $
>> 27 // GEANT4 tag $Name: geant4-08-01-patch-01 $
26 // 28 //
27 // ------------------------------------------- 29 // -------------------------------------------------------------------
28 // 30 //
29 // GEANT4 Class file 31 // GEANT4 Class file
30 // 32 //
31 // 33 //
32 // File name: G4BetheHeitlerModel 34 // File name: G4BetheHeitlerModel
33 // 35 //
34 // Author: Vladimir Ivanchenko on base 36 // Author: Vladimir Ivanchenko on base of Michel Maire code
35 // 37 //
36 // Creation date: 15.03.2005 38 // Creation date: 15.03.2005
37 // 39 //
38 // Modifications by Vladimir Ivanchenko, Miche << 40 // Modifications:
>> 41 // 18-04-05 Use G4ParticleChangeForGamma (V.Ivantchenko)
>> 42 // 24-06-05 Increase number of bins to 200 (V.Ivantchenko)
>> 43 // 16-11-05 replace shootBit() by G4UniformRand() mma
>> 44 // 04-12-05 SetProposedKineticEnergy(0.) for the killed photon (mma)
39 // 45 //
40 // Class Description: 46 // Class Description:
41 // 47 //
42 // ------------------------------------------- 48 // -------------------------------------------------------------------
43 // 49 //
>> 50 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
>> 51 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
44 52
45 #include "G4BetheHeitlerModel.hh" 53 #include "G4BetheHeitlerModel.hh"
46 #include "G4PhysicalConstants.hh" <<
47 #include "G4SystemOfUnits.hh" <<
48 #include "G4Electron.hh" 54 #include "G4Electron.hh"
49 #include "G4Positron.hh" 55 #include "G4Positron.hh"
50 #include "G4Gamma.hh" 56 #include "G4Gamma.hh"
51 #include "Randomize.hh" 57 #include "Randomize.hh"
>> 58 #include "G4DataVector.hh"
>> 59 #include "G4PhysicsLogVector.hh"
52 #include "G4ParticleChangeForGamma.hh" 60 #include "G4ParticleChangeForGamma.hh"
53 #include "G4Pow.hh" <<
54 #include "G4Exp.hh" <<
55 #include "G4ModifiedTsai.hh" <<
56 #include "G4EmParameters.hh" <<
57 #include "G4EmElementXS.hh" <<
58 #include "G4AutoLock.hh" <<
59 61
60 const G4int G4BetheHeitlerModel::gMaxZet = 120 << 62 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
61 std::vector<G4BetheHeitlerModel::ElementData*> <<
62 63
63 namespace << 64 using namespace std;
64 { <<
65 G4Mutex theBetheHMutex = G4MUTEX_INITIALIZER <<
66 } <<
67 65
68 G4BetheHeitlerModel::G4BetheHeitlerModel(const << 66 G4BetheHeitlerModel::G4BetheHeitlerModel(const G4ParticleDefinition*,
69 const << 67 const G4String& nam)
70 : G4VEmModel(nam), << 68 : G4VEmModel(nam),
71 fG4Calc(G4Pow::GetInstance()), fTheGamma(G4G << 69 theCrossSectionTable(0),
72 fTheElectron(G4Electron::Electron()), fThePo << 70 nbins(200)
73 fParticleChange(nullptr) <<
74 { 71 {
75 SetAngularDistribution(new G4ModifiedTsai()) << 72 theGamma = G4Gamma::Gamma();
>> 73 thePositron = G4Positron::Positron();
>> 74 theElectron = G4Electron::Electron();
76 } 75 }
77 76
>> 77 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
>> 78
78 G4BetheHeitlerModel::~G4BetheHeitlerModel() 79 G4BetheHeitlerModel::~G4BetheHeitlerModel()
79 { 80 {
80 if (isFirstInstance) { << 81 if(theCrossSectionTable) {
81 for (auto const & ptr : gElementData) { de << 82 theCrossSectionTable->clearAndDestroy();
82 gElementData.clear(); << 83 delete theCrossSectionTable;
83 } 84 }
84 delete fXSection; <<
85 } 85 }
86 86
87 void G4BetheHeitlerModel::Initialise(const G4P << 87 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
88 const G4D << 88
>> 89 void G4BetheHeitlerModel::Initialise(const G4ParticleDefinition*,
>> 90 const G4DataVector&)
89 { 91 {
90 if (!fParticleChange) { fParticleChange = Ge << 92 if(pParticleChange)
>> 93 fParticleChange = reinterpret_cast<G4ParticleChangeForGamma*>(pParticleChange);
>> 94 else
>> 95 fParticleChange = new G4ParticleChangeForGamma();
>> 96
>> 97 if(theCrossSectionTable) {
>> 98 theCrossSectionTable->clearAndDestroy();
>> 99 delete theCrossSectionTable;
>> 100 }
91 101
92 if (isFirstInstance || gElementData.empty()) << 102 const G4ElementTable* theElementTable = G4Element::GetElementTable();
93 G4AutoLock l(&theBetheHMutex); << 103 size_t nvect = G4Element::GetNumberOfElements();
94 if (gElementData.empty()) { << 104 theCrossSectionTable = new G4PhysicsTable(nvect);
95 isFirstInstance = true; << 105 G4PhysicsLogVector* ptrVector;
96 gElementData.resize(gMaxZet+1, nullptr); << 106 G4double emin = LowEnergyLimit();
97 << 107 G4double emax = HighEnergyLimit();
98 // EPICS2017 flag should be checked only << 108 G4double e, value;
99 useEPICS2017 = G4EmParameters::Instance( << 109
100 if (useEPICS2017) { << 110 for(size_t j=0; j<nvect ; j++) {
101 fXSection = new G4EmElementXS(1, 100, "convE << 111
102 } << 112 ptrVector = new G4PhysicsLogVector(emin, emax, nbins);
>> 113 G4double Z = (*theElementTable)[j]->GetZ();
>> 114 G4int iz = G4int(Z);
>> 115 indexZ[iz] = j;
>> 116
>> 117 for(G4int i=0; i<nbins; i++) {
>> 118 e = ptrVector->GetLowEdgeEnergy( i ) ;
>> 119 value = ComputeCrossSectionPerAtom(theGamma, e, Z);
>> 120 ptrVector->PutValue( i, value );
103 } 121 }
104 // static data should be initialised only << 122
105 InitialiseElementData(); << 123 theCrossSectionTable->insert(ptrVector);
106 l.unlock(); <<
107 } <<
108 // element selectors should be initialised i <<
109 if(IsMaster()) { <<
110 InitialiseElementSelectors(p, cuts); <<
111 } 124 }
112 } 125 }
113 126
114 void G4BetheHeitlerModel::InitialiseLocal(cons << 127 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
115 G4VE <<
116 { <<
117 SetElementSelectors(masterModel->GetElementS <<
118 } <<
119 128
>> 129 G4double G4BetheHeitlerModel::ComputeCrossSectionPerAtom(
>> 130 const G4ParticleDefinition*,
>> 131 G4double GammaEnergy, G4double Z,
>> 132 G4double, G4double, G4double)
120 // Calculates the microscopic cross section in 133 // Calculates the microscopic cross section in GEANT4 internal units.
121 // A parametrized formula from L. Urban is use 134 // A parametrized formula from L. Urban is used to estimate
122 // the total cross section. 135 // the total cross section.
123 // It gives a good description of the data fro 136 // 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 137 // below 1.5 MeV: sigma=sigma(1.5MeV)*(GammaEnergy-2electronmass)
125 // *(GammaEn 138 // *(GammaEnergy-2electronmass)
126 G4double <<
127 G4BetheHeitlerModel::ComputeCrossSectionPerAto <<
128 <<
129 <<
130 { 139 {
131 G4double xSection = 0.0 ; << 140 static const G4double GammaEnergyLimit = 1.5*MeV;
132 // short versions << 141 G4double CrossSection = 0.0 ;
133 static const G4double kMC2 = CLHEP::electro << 142 if ( Z < 1. ) return CrossSection;
134 // zero cross section below the kinematical << 143 if ( GammaEnergy <= 2.0*electron_mass_c2 ) return CrossSection;
135 if (Z < 0.9 || gammaEnergy <= 2.0*kMC2) { re <<
136 <<
137 G4int iZ = G4lrint(Z); <<
138 if (useEPICS2017 && iZ < 101) { <<
139 return fXSection->GetXS(iZ, gammaEnergy); <<
140 } <<
141 144
142 // << 145 static const G4double
143 static const G4double gammaEnergyLimit = 1.5 << 146 a0= 8.7842e+2*microbarn, a1=-1.9625e+3*microbarn, a2= 1.2949e+3*microbarn,
144 // set coefficients a, b c << 147 a3=-2.0028e+2*microbarn, a4= 1.2575e+1*microbarn, a5=-2.8333e-1*microbarn;
145 static const G4double a0 = 8.7842e+2*CLHEP: << 148
146 static const G4double a1 = -1.9625e+3*CLHEP: << 149 static const G4double
147 static const G4double a2 = 1.2949e+3*CLHEP: << 150 b0=-1.0342e+1*microbarn, b1= 1.7692e+1*microbarn, b2=-8.2381 *microbarn,
148 static const G4double a3 = -2.0028e+2*CLHEP: << 151 b3= 1.3063 *microbarn, b4=-9.0815e-2*microbarn, b5= 2.3586e-3*microbarn;
149 static const G4double a4 = 1.2575e+1*CLHEP: << 152
150 static const G4double a5 = -2.8333e-1*CLHEP: << 153 static const G4double
151 << 154 c0=-4.5263e+2*microbarn, c1= 1.1161e+3*microbarn, c2=-8.6749e+2*microbarn,
152 static const G4double b0 = -1.0342e+1*CLHEP: << 155 c3= 2.1773e+2*microbarn, c4=-2.0467e+1*microbarn, c5= 6.5372e-1*microbarn;
153 static const G4double b1 = 1.7692e+1*CLHEP: << 156
154 static const G4double b2 = -8.2381 *CLHEP: << 157 G4double GammaEnergySave = GammaEnergy;
155 static const G4double b3 = 1.3063 *CLHEP: << 158 if (GammaEnergy < GammaEnergyLimit) GammaEnergy = GammaEnergyLimit ;
156 static const G4double b4 = -9.0815e-2*CLHEP: << 159
157 static const G4double b5 = 2.3586e-3*CLHEP: << 160 G4double X=log(GammaEnergy/electron_mass_c2), X2=X*X, X3=X2*X, X4=X3*X, X5=X4*X;
158 << 161
159 static const G4double c0 = -4.5263e+2*CLHEP: << 162 G4double F1 = a0 + a1*X + a2*X2 + a3*X3 + a4*X4 + a5*X5,
160 static const G4double c1 = 1.1161e+3*CLHEP: << 163 F2 = b0 + b1*X + b2*X2 + b3*X3 + b4*X4 + b5*X5,
161 static const G4double c2 = -8.6749e+2*CLHEP: << 164 F3 = c0 + c1*X + c2*X2 + c3*X3 + c4*X4 + c5*X5;
162 static const G4double c3 = 2.1773e+2*CLHEP: << 165
163 static const G4double c4 = -2.0467e+1*CLHEP: << 166 CrossSection = (Z + 1.)*(F1*Z + F2*Z*Z + F3);
164 static const G4double c5 = 6.5372e-1*CLHEP: << 167
165 // check low energy limit of the approximati << 168 if (GammaEnergySave < GammaEnergyLimit) {
166 G4double gammaEnergyOrg = gammaEnergy; << 169
167 if (gammaEnergy < gammaEnergyLimit) { gammaE << 170 X = (GammaEnergySave - 2.*electron_mass_c2)
168 // compute gamma energy variables << 171 / (GammaEnergyLimit - 2.*electron_mass_c2);
169 const G4double x = G4Log(gammaEnergy/kMC2); << 172 CrossSection *= X*X;
170 const G4double x2 = x *x; <<
171 const G4double x3 = x2*x; <<
172 const G4double x4 = x3*x; <<
173 const G4double x5 = x4*x; <<
174 // <<
175 const G4double F1 = a0 + a1*x + a2*x2 + a3*x <<
176 const G4double F2 = b0 + b1*x + b2*x2 + b3*x <<
177 const G4double F3 = c0 + c1*x + c2*x2 + c3*x <<
178 // compute the approximated cross section <<
179 xSection = (Z + 1.)*(F1*Z + F2*Z*Z + F3); <<
180 // check if we are below the limit of the ap <<
181 if (gammaEnergyOrg < gammaEnergyLimit) { <<
182 const G4double dum = (gammaEnergyOrg-2.*kM <<
183 xSection *= dum*dum; <<
184 } 173 }
185 // make sure that the cross section is never << 174
186 xSection = std::max(xSection, 0.); << 175 if (CrossSection < 0.) CrossSection = 0.;
187 return xSection; << 176 return CrossSection;
188 } 177 }
189 178
>> 179 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
>> 180
>> 181 std::vector<G4DynamicParticle*>* G4BetheHeitlerModel::SampleSecondaries(
>> 182 const G4MaterialCutsCouple* couple,
>> 183 const G4DynamicParticle* aDynamicGamma,
>> 184 G4double,
>> 185 G4double)
190 // The secondaries e+e- energies are sampled u 186 // The secondaries e+e- energies are sampled using the Bethe - Heitler
191 // cross sections with Coulomb correction. 187 // cross sections with Coulomb correction.
192 // A modified version of the random number tec 188 // A modified version of the random number techniques of Butcher & Messel
193 // is used (Nuc Phys 20(1960),15). 189 // is used (Nuc Phys 20(1960),15).
194 // 190 //
195 // GEANT4 internal units. 191 // GEANT4 internal units.
196 // 192 //
197 // Note 1 : Effects due to the breakdown of th 193 // Note 1 : Effects due to the breakdown of the Born approximation at
198 // low energy are ignored. 194 // low energy are ignored.
199 // Note 2 : The differential cross section imp 195 // Note 2 : The differential cross section implicitly takes account of
200 // pair creation in both nuclear and 196 // pair creation in both nuclear and atomic electron fields.
201 // However triplet prodution is not g 197 // However triplet prodution is not generated.
202 void G4BetheHeitlerModel::SampleSecondaries(st <<
203 co <<
204 co <<
205 G4 <<
206 { 198 {
207 // set some constant values << 199 const G4Material* aMaterial = couple->GetMaterial();
208 const G4double gammaEnergy = aDynamicGamm << 200
209 const G4double eps0 = CLHEP::elect << 201 G4double GammaEnergy = aDynamicGamma->GetKineticEnergy();
210 // << 202 G4ParticleMomentum GammaDirection = aDynamicGamma->GetMomentumDirection();
211 // check kinematical limit: gamma energy(Eg) << 203
212 if (eps0 > 0.5) { return; } << 204 G4double epsil ;
213 // << 205 G4double epsil0 = electron_mass_c2/GammaEnergy ;
214 // select target element of the material (pr << 206 if(epsil0 > 1.0) return 0;
215 const G4Element* anElement = SelectTargetAto << 207
216 aDyn << 208 // do it fast if GammaEnergy < 2. MeV
217 << 209 static const G4double Egsmall=2.*MeV;
218 // << 210
219 // get the random engine << 211 if (GammaEnergy < Egsmall) {
220 CLHEP::HepRandomEngine* rndmEngine = G4Rando << 212
221 // << 213 epsil = epsil0 + (0.5-epsil0)*G4UniformRand();
222 // 'eps' is the total energy transferred to << 214
223 // gamma energy units Eg. Since the correspo <<
224 // the kinematical limits for eps0=mc^2/Eg < <<
225 // 1. 'eps' is sampled uniformly on the [eps <<
226 // 2. otherwise, on the [eps_min, 0.5] inter <<
227 G4double eps; <<
228 // case 1. <<
229 static const G4double Egsmall = 2.*CLHEP::Me <<
230 if (gammaEnergy < Egsmall) { <<
231 eps = eps0 + (0.5-eps0)*rndmEngine->flat() <<
232 } else { 215 } else {
233 // case 2. << 216 // now comes the case with GammaEnergy >= 2. MeV
234 // get the Coulomb factor for the target e << 217 // select randomly one element constituing the material
235 // F(Z) = 8*ln(Z)/3 if Eg <= 50 << 218 const G4Element* anElement = SelectRandomAtom(aMaterial, theGamma, GammaEnergy);
236 // F(Z) = 8*ln(Z)/3 + 8*fc(Z) if Eg > 50 << 219
>> 220 // Extract Coulomb factor for this Element
>> 221 G4double FZ = 8.*(anElement->GetIonisation()->GetlogZ3());
>> 222 if (GammaEnergy > 50.*MeV) FZ += 8.*(anElement->GetfCoulomb());
>> 223
>> 224 // limits of the screening variable
>> 225 G4double screenfac = 136.*epsil0/(anElement->GetIonisation()->GetZ3());
>> 226 G4double screenmax = exp ((42.24 - FZ)/8.368) - 0.952 ;
>> 227 G4double screenmin = min(4.*screenfac,screenmax);
>> 228
>> 229 // limits of the energy sampling
>> 230 G4double epsil1 = 0.5 - 0.5*sqrt(1. - screenmin/screenmax) ;
>> 231 G4double epsilmin = max(epsil0,epsil1) , epsilrange = 0.5 - epsilmin;
>> 232
237 // 233 //
238 // The screening variable 'delta(eps)' = 1 << 234 // sample the energy rate of the created electron (or positron)
239 // Due to the Coulomb correction, the DCS <<
240 // kinematicaly allowed eps > eps0 values. <<
241 // range with negative DCS, the minimum ep <<
242 // max[eps0, epsp] with epsp is the soluti <<
243 // with SF being the screening function (S <<
244 // The solution is epsp = 0.5 - 0.5*sqrt[ <<
245 // with deltap = Exp[(42.038-F(Z))/8.29]-0 <<
246 // - when eps=eps_max = 0.5 => <<
247 // - epsp = 0.5 - 0.5*sqrt[ 1 - delta_min/ <<
248 // - and eps_min = max[eps0, epsp] <<
249 static const G4double midEnergy = 50.*CLHE <<
250 const G4int iZet = std::min(gMa <<
251 const G4double deltaFactor = 136.*eps0/an <<
252 G4double deltaMax = gElementData <<
253 G4double FZ = 8.*anElement <<
254 if (gammaEnergy > midEnergy) { <<
255 FZ += 8.*(anElement->GetfCoulomb()) <<
256 deltaMax = gElementData[iZet]->fDeltaMax <<
257 } <<
258 const G4double deltaMin = 4.*deltaFactor; <<
259 // <<
260 // compute the limits of eps <<
261 const G4double epsp = 0.5 - 0.5*std::s <<
262 const G4double epsMin = std::max(eps0,ep <<
263 const G4double epsRange = 0.5 - epsMin; <<
264 // 235 //
265 // sample the energy rate (eps) of the cre << 236 //G4double epsil, screenvar, greject ;
266 G4double F10, F20; << 237 G4double screenvar, greject ;
267 ScreenFunction12(deltaMin, F10, F20); << 238
268 F10 -= FZ; << 239 G4double F10 = ScreenFunction1(screenmin) - FZ;
269 F20 -= FZ; << 240 G4double F20 = ScreenFunction2(screenmin) - FZ;
270 const G4double NormF1 = std::max(F10 * e << 241 G4double NormF1 = max(F10*epsilrange*epsilrange,0.);
271 const G4double NormF2 = std::max(1.5 * F << 242 G4double NormF2 = max(1.5*F20,0.);
272 const G4double NormCond = NormF1/(NormF1 + << 243
273 // we will need 3 uniform random number fo <<
274 G4double rndmv[3]; <<
275 G4double greject = 0.; <<
276 do { 244 do {
277 rndmEngine->flatArray(3, rndmv); << 245 if ( NormF1/(NormF1+NormF2) > G4UniformRand() ) {
278 if (NormCond > rndmv[0]) { << 246 epsil = 0.5 - epsilrange*pow(G4UniformRand(), 0.333333);
279 eps = 0.5 - epsRange * fG4Calc->A13(rn << 247 screenvar = screenfac/(epsil*(1-epsil));
280 const G4double delta = deltaFactor/(ep << 248 greject = (ScreenFunction1(screenvar) - FZ)/F10;
281 greject = (ScreenFunction1(delta)-FZ)/ << 249
282 } else { 250 } else {
283 eps = epsMin + epsRange*rndmv[1]; << 251 epsil = epsilmin + epsilrange*G4UniformRand();
284 const G4double delta = deltaFactor/(ep << 252 screenvar = screenfac/(epsil*(1-epsil));
285 greject = (ScreenFunction2(delta)-FZ)/ << 253 greject = (ScreenFunction2(screenvar) - FZ)/F20;
286 } 254 }
287 // Loop checking, 03-Aug-2015, Vladimir << 255
288 } while (greject < rndmv[2]); << 256 } while( greject < G4UniformRand() );
289 } // end of eps sampling << 257
>> 258 } // end of epsil sampling
>> 259
>> 260 //
>> 261 // fixe charges randomly
290 // 262 //
291 // select charges randomly << 263
292 G4double eTotEnergy, pTotEnergy; << 264 G4double ElectTotEnergy, PositTotEnergy;
293 if (rndmEngine->flat() > 0.5) { << 265 if (G4UniformRand() > 0.5) {
294 eTotEnergy = (1.-eps)*gammaEnergy; << 266
295 pTotEnergy = eps*gammaEnergy; << 267 ElectTotEnergy = (1.-epsil)*GammaEnergy;
>> 268 PositTotEnergy = epsil*GammaEnergy;
>> 269
296 } else { 270 } else {
297 pTotEnergy = (1.-eps)*gammaEnergy; << 271
298 eTotEnergy = eps*gammaEnergy; << 272 PositTotEnergy = (1.-epsil)*GammaEnergy;
>> 273 ElectTotEnergy = epsil*GammaEnergy;
299 } 274 }
>> 275
>> 276 //
>> 277 // scattered electron (positron) angles. ( Z - axis along the parent photon)
300 // 278 //
301 // sample pair kinematics << 279 // universal distribution suggested by L. Urban
302 const G4double eKinEnergy = std::max(0.,eTot << 280 // (Geant3 manual (1993) Phys211),
303 const G4double pKinEnergy = std::max(0.,pTot << 281 // derived from Tsai distribution (Rev Mod Phys 49,421(1977))
>> 282
>> 283 G4double u;
>> 284 const G4double a1 = 0.625 , a2 = 3.*a1 , d = 27. ;
>> 285
>> 286 if (9./(9.+d) >G4UniformRand()) u= - log(G4UniformRand()*G4UniformRand())/a1;
>> 287 else u= - log(G4UniformRand()*G4UniformRand())/a2;
>> 288
>> 289 G4double TetEl = u*electron_mass_c2/ElectTotEnergy;
>> 290 G4double TetPo = u*electron_mass_c2/PositTotEnergy;
>> 291 G4double Phi = twopi * G4UniformRand();
>> 292 G4double dxEl= sin(TetEl)*cos(Phi),dyEl= sin(TetEl)*sin(Phi),dzEl=cos(TetEl);
>> 293 G4double dxPo=-sin(TetPo)*cos(Phi),dyPo=-sin(TetPo)*sin(Phi),dzPo=cos(TetPo);
>> 294
304 // 295 //
305 G4ThreeVector eDirection, pDirection; << 296 // kinematic of the created pair
306 // 297 //
307 GetAngularDistribution()->SamplePairDirectio << 298 // the electron and positron are assumed to have a symetric
308 << 299 // angular distribution with respect to the Z axis along the parent photon.
309 << 300
310 // create G4DynamicParticle object for the p << 301 G4double ElectKineEnergy = max(0.,ElectTotEnergy - electron_mass_c2);
311 auto aParticle1= new G4DynamicParticle(fTheE << 302
312 // create G4DynamicParticle object for the p << 303 G4ThreeVector ElectDirection (dxEl, dyEl, dzEl);
313 auto aParticle2= new G4DynamicParticle(fTheP << 304 ElectDirection.rotateUz(GammaDirection);
>> 305
>> 306 // create G4DynamicParticle object for the particle1
>> 307 G4DynamicParticle* aParticle1= new G4DynamicParticle(
>> 308 theElectron,ElectDirection,ElectKineEnergy);
>> 309
>> 310 // the e+ is always created (even with Ekine=0) for further annihilation.
>> 311
>> 312 G4double PositKineEnergy = max(0.,PositTotEnergy - electron_mass_c2);
>> 313
>> 314 G4ThreeVector PositDirection (dxPo, dyPo, dzPo);
>> 315 PositDirection.rotateUz(GammaDirection);
>> 316
>> 317 // create G4DynamicParticle object for the particle2
>> 318 G4DynamicParticle* aParticle2= new G4DynamicParticle(
>> 319 thePositron,PositDirection,PositKineEnergy);
>> 320
314 // Fill output vector 321 // Fill output vector
>> 322 std::vector<G4DynamicParticle*>* fvect = new std::vector<G4DynamicParticle*>;
315 fvect->push_back(aParticle1); 323 fvect->push_back(aParticle1);
316 fvect->push_back(aParticle2); 324 fvect->push_back(aParticle2);
>> 325
317 // kill incident photon 326 // kill incident photon
318 fParticleChange->SetProposedKineticEnergy(0. 327 fParticleChange->SetProposedKineticEnergy(0.);
319 fParticleChange->ProposeTrackStatus(fStopAnd 328 fParticleChange->ProposeTrackStatus(fStopAndKill);
>> 329
>> 330 return fvect;
320 } 331 }
321 332
322 // should be called only by the master and at << 333 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
323 void G4BetheHeitlerModel::InitialiseElementDat << 334
324 { <<
325 // create for all elements that are in the d <<
326 auto elemTable = G4Element::GetElementTable( <<
327 for (auto const & elem : *elemTable) { <<
328 const G4int Z = elem->GetZasInt(); <<
329 const G4int iz = std::min(gMaxZet, Z); <<
330 if (nullptr == gElementData[iz]) { // crea <<
331 G4double FZLow = 8.*elem->GetIonisat <<
332 G4double FZHigh = FZLow + 8.*elem->Ge <<
333 auto elD = new ElementData(); <<
334 elD->fDeltaMaxLow = G4Exp((42.038 - FZL <<
335 elD->fDeltaMaxHigh = G4Exp((42.038 - FZH <<
336 gElementData[iz] = elD; <<
337 } <<
338 if (useEPICS2017 && Z < 101) { <<
339 fXSection->Retrieve(Z); <<
340 } <<
341 } <<
342 <<
343 } <<
344 335
345 336