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25 // 25 //
>> 26 // $Id$
26 // 27 //
27 // ------------------------------------------- 28 // -------------------------------------------------------------------
28 // 29 //
29 // GEANT4 Class file 30 // GEANT4 Class file
30 // 31 //
31 // 32 //
32 // File name: G4BetheHeitlerModel 33 // File name: G4BetheHeitlerModel
33 // 34 //
34 // Author: Vladimir Ivanchenko on base 35 // Author: Vladimir Ivanchenko on base of Michel Maire code
35 // 36 //
36 // Creation date: 15.03.2005 37 // Creation date: 15.03.2005
37 // 38 //
38 // Modifications by Vladimir Ivanchenko, Miche << 39 // Modifications:
>> 40 // 18-04-05 Use G4ParticleChangeForGamma (V.Ivantchenko)
>> 41 // 24-06-05 Increase number of bins to 200 (V.Ivantchenko)
>> 42 // 16-11-05 replace shootBit() by G4UniformRand() mma
>> 43 // 04-12-05 SetProposedKineticEnergy(0.) for the killed photon (mma)
>> 44 // 20-02-07 SelectRandomElement is called for any initial gamma energy
>> 45 // in order to have selected element for polarized model (VI)
>> 46 // 25-10-10 Removed unused table, added element selector (VI)
39 // 47 //
40 // Class Description: 48 // Class Description:
41 // 49 //
42 // ------------------------------------------- 50 // -------------------------------------------------------------------
43 // 51 //
>> 52 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
>> 53 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
44 54
45 #include "G4BetheHeitlerModel.hh" 55 #include "G4BetheHeitlerModel.hh"
46 #include "G4PhysicalConstants.hh" 56 #include "G4PhysicalConstants.hh"
47 #include "G4SystemOfUnits.hh" 57 #include "G4SystemOfUnits.hh"
48 #include "G4Electron.hh" 58 #include "G4Electron.hh"
49 #include "G4Positron.hh" 59 #include "G4Positron.hh"
50 #include "G4Gamma.hh" 60 #include "G4Gamma.hh"
51 #include "Randomize.hh" 61 #include "Randomize.hh"
52 #include "G4ParticleChangeForGamma.hh" 62 #include "G4ParticleChangeForGamma.hh"
53 #include "G4Pow.hh" 63 #include "G4Pow.hh"
54 #include "G4Exp.hh" <<
55 #include "G4ModifiedTsai.hh" <<
56 #include "G4EmParameters.hh" <<
57 #include "G4EmElementXS.hh" <<
58 #include "G4AutoLock.hh" <<
59 64
60 const G4int G4BetheHeitlerModel::gMaxZet = 120 << 65 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
61 std::vector<G4BetheHeitlerModel::ElementData*> <<
62 66
63 namespace << 67 using namespace std;
64 { << 68
65 G4Mutex theBetheHMutex = G4MUTEX_INITIALIZER << 69 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
66 } <<
67 70
68 G4BetheHeitlerModel::G4BetheHeitlerModel(const << 71 G4BetheHeitlerModel::G4BetheHeitlerModel(const G4ParticleDefinition*,
69 const << 72 const G4String& nam)
70 : G4VEmModel(nam), << 73 : G4VEmModel(nam)
71 fG4Calc(G4Pow::GetInstance()), fTheGamma(G4G <<
72 fTheElectron(G4Electron::Electron()), fThePo <<
73 fParticleChange(nullptr) <<
74 { 74 {
75 SetAngularDistribution(new G4ModifiedTsai()) << 75 fParticleChange = nullptr;
>> 76 theGamma = G4Gamma::Gamma();
>> 77 thePositron = G4Positron::Positron();
>> 78 theElectron = G4Electron::Electron();
>> 79 g4calc = G4Pow::GetInstance();
76 } 80 }
77 81
>> 82 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
>> 83
78 G4BetheHeitlerModel::~G4BetheHeitlerModel() 84 G4BetheHeitlerModel::~G4BetheHeitlerModel()
79 { << 85 {}
80 if (isFirstInstance) { <<
81 for (auto const & ptr : gElementData) { de <<
82 gElementData.clear(); <<
83 } <<
84 delete fXSection; <<
85 } <<
86 86
87 void G4BetheHeitlerModel::Initialise(const G4P << 87 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
88 const G4D <<
89 { <<
90 if (!fParticleChange) { fParticleChange = Ge <<
91 88
92 if (isFirstInstance || gElementData.empty()) << 89 void G4BetheHeitlerModel::Initialise(const G4ParticleDefinition* p,
93 G4AutoLock l(&theBetheHMutex); << 90 const G4DataVector& cuts)
94 if (gElementData.empty()) { << 91 {
95 isFirstInstance = true; << 92 if(!fParticleChange) { fParticleChange = GetParticleChangeForGamma(); }
96 gElementData.resize(gMaxZet+1, nullptr); << 93 if(IsMaster()) { InitialiseElementSelectors(p, cuts); }
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(); <<
106 l.unlock(); <<
107 } <<
108 // element selectors should be initialised i <<
109 if(IsMaster()) { <<
110 InitialiseElementSelectors(p, cuts); <<
111 } <<
112 } 94 }
113 95
114 void G4BetheHeitlerModel::InitialiseLocal(cons << 96 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
115 G4VE << 97
>> 98 void G4BetheHeitlerModel::InitialiseLocal(const G4ParticleDefinition*,
>> 99 G4VEmModel* masterModel)
116 { 100 {
117 SetElementSelectors(masterModel->GetElementS 101 SetElementSelectors(masterModel->GetElementSelectors());
118 } 102 }
119 103
>> 104 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
>> 105
>> 106 G4double
>> 107 G4BetheHeitlerModel::ComputeCrossSectionPerAtom(const G4ParticleDefinition*,
>> 108 G4double GammaEnergy, G4double Z,
>> 109 G4double, G4double, G4double)
120 // Calculates the microscopic cross section in 110 // Calculates the microscopic cross section in GEANT4 internal units.
121 // A parametrized formula from L. Urban is use 111 // A parametrized formula from L. Urban is used to estimate
122 // the total cross section. 112 // the total cross section.
123 // It gives a good description of the data fro 113 // 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 114 // below 1.5 MeV: sigma=sigma(1.5MeV)*(GammaEnergy-2electronmass)
125 // *(GammaEn 115 // *(GammaEnergy-2electronmass)
126 G4double <<
127 G4BetheHeitlerModel::ComputeCrossSectionPerAto <<
128 <<
129 <<
130 { 116 {
131 G4double xSection = 0.0 ; 117 G4double xSection = 0.0 ;
132 // short versions << 118 if ( Z < 0.9 || GammaEnergy <= 2.0*electron_mass_c2 ) { return xSection; }
133 static const G4double kMC2 = CLHEP::electro << 119
134 // zero cross section below the kinematical << 120 static const G4double GammaEnergyLimit = 1.5*MeV;
135 if (Z < 0.9 || gammaEnergy <= 2.0*kMC2) { re << 121 static const G4double
136 << 122 a0= 8.7842e+2*microbarn, a1=-1.9625e+3*microbarn, a2= 1.2949e+3*microbarn,
137 G4int iZ = G4lrint(Z); << 123 a3=-2.0028e+2*microbarn, a4= 1.2575e+1*microbarn, a5=-2.8333e-1*microbarn;
138 if (useEPICS2017 && iZ < 101) { << 124
139 return fXSection->GetXS(iZ, gammaEnergy); << 125 static const G4double
140 } << 126 b0=-1.0342e+1*microbarn, b1= 1.7692e+1*microbarn, b2=-8.2381 *microbarn,
>> 127 b3= 1.3063 *microbarn, b4=-9.0815e-2*microbarn, b5= 2.3586e-3*microbarn;
>> 128
>> 129 static const G4double
>> 130 c0=-4.5263e+2*microbarn, c1= 1.1161e+3*microbarn, c2=-8.6749e+2*microbarn,
>> 131 c3= 2.1773e+2*microbarn, c4=-2.0467e+1*microbarn, c5= 6.5372e-1*microbarn;
>> 132
>> 133 G4double GammaEnergySave = GammaEnergy;
>> 134 if (GammaEnergy < GammaEnergyLimit) { GammaEnergy = GammaEnergyLimit; }
>> 135
>> 136 G4double X=G4Log(GammaEnergy/electron_mass_c2), X2=X*X, X3=X2*X, X4=X3*X, X5=X4*X;
>> 137
>> 138 G4double F1 = a0 + a1*X + a2*X2 + a3*X3 + a4*X4 + a5*X5,
>> 139 F2 = b0 + b1*X + b2*X2 + b3*X3 + b4*X4 + b5*X5,
>> 140 F3 = c0 + c1*X + c2*X2 + c3*X3 + c4*X4 + c5*X5;
141 141
142 // <<
143 static const G4double gammaEnergyLimit = 1.5 <<
144 // set coefficients a, b c <<
145 static const G4double a0 = 8.7842e+2*CLHEP: <<
146 static const G4double a1 = -1.9625e+3*CLHEP: <<
147 static const G4double a2 = 1.2949e+3*CLHEP: <<
148 static const G4double a3 = -2.0028e+2*CLHEP: <<
149 static const G4double a4 = 1.2575e+1*CLHEP: <<
150 static const G4double a5 = -2.8333e-1*CLHEP: <<
151 <<
152 static const G4double b0 = -1.0342e+1*CLHEP: <<
153 static const G4double b1 = 1.7692e+1*CLHEP: <<
154 static const G4double b2 = -8.2381 *CLHEP: <<
155 static const G4double b3 = 1.3063 *CLHEP: <<
156 static const G4double b4 = -9.0815e-2*CLHEP: <<
157 static const G4double b5 = 2.3586e-3*CLHEP: <<
158 <<
159 static const G4double c0 = -4.5263e+2*CLHEP: <<
160 static const G4double c1 = 1.1161e+3*CLHEP: <<
161 static const G4double c2 = -8.6749e+2*CLHEP: <<
162 static const G4double c3 = 2.1773e+2*CLHEP: <<
163 static const G4double c4 = -2.0467e+1*CLHEP: <<
164 static const G4double c5 = 6.5372e-1*CLHEP: <<
165 // check low energy limit of the approximati <<
166 G4double gammaEnergyOrg = gammaEnergy; <<
167 if (gammaEnergy < gammaEnergyLimit) { gammaE <<
168 // compute gamma energy variables <<
169 const G4double x = G4Log(gammaEnergy/kMC2); <<
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); 142 xSection = (Z + 1.)*(F1*Z + F2*Z*Z + F3);
180 // check if we are below the limit of the ap << 143
181 if (gammaEnergyOrg < gammaEnergyLimit) { << 144 if (GammaEnergySave < GammaEnergyLimit) {
182 const G4double dum = (gammaEnergyOrg-2.*kM << 145
183 xSection *= dum*dum; << 146 X = (GammaEnergySave - 2.*electron_mass_c2)
>> 147 / (GammaEnergyLimit - 2.*electron_mass_c2);
>> 148 xSection *= X*X;
184 } 149 }
185 // make sure that the cross section is never << 150
186 xSection = std::max(xSection, 0.); 151 xSection = std::max(xSection, 0.);
187 return xSection; 152 return xSection;
188 } 153 }
189 154
>> 155 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
>> 156
>> 157 void G4BetheHeitlerModel::SampleSecondaries(std::vector<G4DynamicParticle*>* fvect,
>> 158 const G4MaterialCutsCouple* couple,
>> 159 const G4DynamicParticle* aDynamicGamma,
>> 160 G4double,
>> 161 G4double)
190 // The secondaries e+e- energies are sampled u 162 // The secondaries e+e- energies are sampled using the Bethe - Heitler
191 // cross sections with Coulomb correction. 163 // cross sections with Coulomb correction.
192 // A modified version of the random number tec 164 // A modified version of the random number techniques of Butcher & Messel
193 // is used (Nuc Phys 20(1960),15). 165 // is used (Nuc Phys 20(1960),15).
194 // 166 //
195 // GEANT4 internal units. 167 // GEANT4 internal units.
196 // 168 //
197 // Note 1 : Effects due to the breakdown of th 169 // Note 1 : Effects due to the breakdown of the Born approximation at
198 // low energy are ignored. 170 // low energy are ignored.
199 // Note 2 : The differential cross section imp 171 // Note 2 : The differential cross section implicitly takes account of
200 // pair creation in both nuclear and 172 // pair creation in both nuclear and atomic electron fields.
201 // However triplet prodution is not g 173 // However triplet prodution is not generated.
202 void G4BetheHeitlerModel::SampleSecondaries(st <<
203 co <<
204 co <<
205 G4 <<
206 { 174 {
207 // set some constant values << 175 const G4Material* aMaterial = couple->GetMaterial();
208 const G4double gammaEnergy = aDynamicGamm << 176
209 const G4double eps0 = CLHEP::elect << 177 G4double GammaEnergy = aDynamicGamma->GetKineticEnergy();
210 // << 178 G4ParticleMomentum GammaDirection = aDynamicGamma->GetMomentumDirection();
211 // check kinematical limit: gamma energy(Eg) << 179
212 if (eps0 > 0.5) { return; } << 180 G4double epsil ;
213 // << 181 G4double epsil0 = electron_mass_c2/GammaEnergy;
214 // select target element of the material (pr << 182 if(epsil0 > 1.0) { return; }
215 const G4Element* anElement = SelectTargetAto << 183
216 aDyn << 184 // do it fast if GammaEnergy < Egsmall
>> 185 // select randomly one element constituing the material
>> 186 const G4Element* anElement =
>> 187 SelectRandomAtom(aMaterial, theGamma, GammaEnergy);
217 188
218 // <<
219 // get the random engine <<
220 CLHEP::HepRandomEngine* rndmEngine = G4Rando 189 CLHEP::HepRandomEngine* rndmEngine = G4Random::getTheEngine();
221 // << 190
222 // 'eps' is the total energy transferred to << 191 static const G4double Egsmall=2.*CLHEP::MeV;
223 // gamma energy units Eg. Since the correspo << 192 if (GammaEnergy < Egsmall) {
224 // the kinematical limits for eps0=mc^2/Eg < << 193
225 // 1. 'eps' is sampled uniformly on the [eps << 194 epsil = epsil0 + (0.5-epsil0)*rndmEngine->flat();
226 // 2. otherwise, on the [eps_min, 0.5] inter << 195
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 { 196 } else {
233 // case 2. << 197 // now comes the case with GammaEnergy >= 2. MeV
234 // get the Coulomb factor for the target e << 198
235 // F(Z) = 8*ln(Z)/3 if Eg <= 50 << 199 // Extract Coulomb factor for this Element
236 // F(Z) = 8*ln(Z)/3 + 8*fc(Z) if Eg > 50 << 200 G4double FZ = 8.*(anElement->GetIonisation()->GetlogZ3());
237 // <<
238 // The screening variable 'delta(eps)' = 1 <<
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 201 static const G4double midEnergy = 50.*CLHEP::MeV;
250 const G4int iZet = std::min(gMa << 202 if (GammaEnergy > midEnergy) { FZ += 8.*(anElement->GetfCoulomb()); }
251 const G4double deltaFactor = 136.*eps0/an << 203
252 G4double deltaMax = gElementData << 204 // limits of the screening variable
253 G4double FZ = 8.*anElement << 205 G4double screenfac = 136.*epsil0/(anElement->GetIonisation()->GetZ3());
254 if (gammaEnergy > midEnergy) { << 206 G4double screenmax = G4Exp ((42.24 - FZ)/8.368) + 0.952 ;
255 FZ += 8.*(anElement->GetfCoulomb()) << 207 G4double screenmin = std::min(4.*screenfac, screenmax);
256 deltaMax = gElementData[iZet]->fDeltaMax << 208
257 } << 209 // limits of the energy sampling
258 const G4double deltaMin = 4.*deltaFactor; << 210 G4double epsil1 = 0.5 - 0.5*sqrt(1. - screenmin/screenmax) ;
259 // << 211 G4double epsilmin = std::max(epsil0,epsil1);
260 // compute the limits of eps << 212 G4double epsilrange = 0.5 - epsilmin;
261 const G4double epsp = 0.5 - 0.5*std::s << 213
262 const G4double epsMin = std::max(eps0,ep <<
263 const G4double epsRange = 0.5 - epsMin; <<
264 // 214 //
265 // sample the energy rate (eps) of the cre << 215 // sample the energy rate of the created electron (or positron)
266 G4double F10, F20; << 216 //
267 ScreenFunction12(deltaMin, F10, F20); << 217 //G4double epsil, screenvar, greject ;
268 F10 -= FZ; << 218 G4double screenvar, greject ;
269 F20 -= FZ; << 219
270 const G4double NormF1 = std::max(F10 * e << 220 G4double F10 = ScreenFunction1(screenmin) - FZ;
271 const G4double NormF2 = std::max(1.5 * F << 221 G4double F20 = ScreenFunction2(screenmin) - FZ;
272 const G4double NormCond = NormF1/(NormF1 + << 222 G4double NormF1 = std::max(F10*epsilrange*epsilrange, 0.);
273 // we will need 3 uniform random number fo << 223 G4double NormF2 = std::max(1.5*F20, 0.);
274 G4double rndmv[3]; << 224
275 G4double greject = 0.; <<
276 do { 225 do {
277 rndmEngine->flatArray(3, rndmv); << 226 if ( NormF1/(NormF1+NormF2) > rndmEngine->flat()) {
278 if (NormCond > rndmv[0]) { << 227 epsil = 0.5 - epsilrange*g4calc->A13(rndmEngine->flat());
279 eps = 0.5 - epsRange * fG4Calc->A13(rn << 228 screenvar = screenfac/(epsil*(1-epsil));
280 const G4double delta = deltaFactor/(ep << 229 greject = (ScreenFunction1(screenvar) - FZ)/F10;
281 greject = (ScreenFunction1(delta)-FZ)/ << 230
282 } else { 231 } else {
283 eps = epsMin + epsRange*rndmv[1]; << 232 epsil = epsilmin + epsilrange*rndmEngine->flat();
284 const G4double delta = deltaFactor/(ep << 233 screenvar = screenfac/(epsil*(1-epsil));
285 greject = (ScreenFunction2(delta)-FZ)/ << 234 greject = (ScreenFunction2(screenvar) - FZ)/F20;
286 } 235 }
>> 236
287 // Loop checking, 03-Aug-2015, Vladimir 237 // Loop checking, 03-Aug-2015, Vladimir Ivanchenko
288 } while (greject < rndmv[2]); << 238 } while( greject < rndmEngine->flat());
289 } // end of eps sampling << 239
>> 240 } // end of epsil sampling
>> 241
>> 242 //
>> 243 // fixe charges randomly
290 // 244 //
291 // select charges randomly << 245
292 G4double eTotEnergy, pTotEnergy; << 246 G4double ElectTotEnergy, PositTotEnergy;
293 if (rndmEngine->flat() > 0.5) { 247 if (rndmEngine->flat() > 0.5) {
294 eTotEnergy = (1.-eps)*gammaEnergy; << 248
295 pTotEnergy = eps*gammaEnergy; << 249 ElectTotEnergy = (1.-epsil)*GammaEnergy;
>> 250 PositTotEnergy = epsil*GammaEnergy;
>> 251
296 } else { 252 } else {
297 pTotEnergy = (1.-eps)*gammaEnergy; << 253
298 eTotEnergy = eps*gammaEnergy; << 254 PositTotEnergy = (1.-epsil)*GammaEnergy;
>> 255 ElectTotEnergy = epsil*GammaEnergy;
299 } 256 }
>> 257
>> 258 //
>> 259 // scattered electron (positron) angles. ( Z - axis along the parent photon)
300 // 260 //
301 // sample pair kinematics << 261 // universal distribution suggested by L. Urban
302 const G4double eKinEnergy = std::max(0.,eTot << 262 // (Geant3 manual (1993) Phys211),
303 const G4double pKinEnergy = std::max(0.,pTot << 263 // derived from Tsai distribution (Rev Mod Phys 49,421(1977))
>> 264
>> 265 static const G4double a1 = 1.6;
>> 266 static const G4double a2 = a1/3.;
>> 267 G4double uu = -G4Log(rndmEngine->flat()*rndmEngine->flat());
>> 268 G4double u = (0.25 > rndmEngine->flat()) ? uu*a1 : uu*a2;
>> 269
>> 270 G4double thetaEle = u*electron_mass_c2/ElectTotEnergy;
>> 271 G4double sinte = std::sin(thetaEle);
>> 272 G4double coste = std::cos(thetaEle);
>> 273
>> 274 G4double thetaPos = u*electron_mass_c2/PositTotEnergy;
>> 275 G4double sintp = std::sin(thetaPos);
>> 276 G4double costp = std::cos(thetaPos);
>> 277
>> 278 G4double phi = twopi * rndmEngine->flat();
>> 279 G4double sinp = std::sin(phi);
>> 280 G4double cosp = std::cos(phi);
>> 281
304 // 282 //
305 G4ThreeVector eDirection, pDirection; << 283 // kinematic of the created pair
306 // 284 //
307 GetAngularDistribution()->SamplePairDirectio << 285 // the electron and positron are assumed to have a symetric
308 << 286 // angular distribution with respect to the Z axis along the parent photon.
309 << 287
310 // create G4DynamicParticle object for the p << 288 G4double ElectKineEnergy = std::max(0.,ElectTotEnergy - electron_mass_c2);
311 auto aParticle1= new G4DynamicParticle(fTheE << 289
312 // create G4DynamicParticle object for the p << 290 G4ThreeVector ElectDirection (sinte*cosp, sinte*sinp, coste);
313 auto aParticle2= new G4DynamicParticle(fTheP << 291 ElectDirection.rotateUz(GammaDirection);
>> 292
>> 293 // create G4DynamicParticle object for the particle1
>> 294 G4DynamicParticle* aParticle1= new G4DynamicParticle(
>> 295 theElectron,ElectDirection,ElectKineEnergy);
>> 296
>> 297 // the e+ is always created (even with Ekine=0) for further annihilation.
>> 298
>> 299 G4double PositKineEnergy = std::max(0.,PositTotEnergy - electron_mass_c2);
>> 300 G4ThreeVector PositDirection (-sintp*cosp, -sintp*sinp, costp);
>> 301 PositDirection.rotateUz(GammaDirection);
>> 302
>> 303 // create G4DynamicParticle object for the particle2
>> 304 G4DynamicParticle* aParticle2= new G4DynamicParticle(
>> 305 thePositron,PositDirection,PositKineEnergy);
>> 306
314 // Fill output vector 307 // Fill output vector
315 fvect->push_back(aParticle1); 308 fvect->push_back(aParticle1);
316 fvect->push_back(aParticle2); 309 fvect->push_back(aParticle2);
>> 310
317 // kill incident photon 311 // kill incident photon
318 fParticleChange->SetProposedKineticEnergy(0. 312 fParticleChange->SetProposedKineticEnergy(0.);
319 fParticleChange->ProposeTrackStatus(fStopAnd 313 fParticleChange->ProposeTrackStatus(fStopAndKill);
320 } 314 }
321 315
322 // should be called only by the master and at << 316 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
323 void G4BetheHeitlerModel::InitialiseElementDat <<
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 <<
345 317