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25 // 25 //
>> 26 // $Id: G4PenelopeGammaConversionModel.cc,v 1.2 2008/12/04 14:09:36 pandola Exp $
>> 27 // GEANT4 tag $Name: geant4-09-02-patch-01 $
26 // 28 //
27 // Author: Luciano Pandola 29 // Author: Luciano Pandola
28 // 30 //
29 // History: 31 // History:
30 // -------- 32 // --------
31 // 13 Jan 2010 L Pandola First implementa << 33 // 06 Oct 2008 L Pandola Migration from process to model
32 // 24 May 2011 L Pandola Renamed (make v2 <<
33 // 18 Sep 2013 L Pandola Migration to MT <<
34 // data and create <<
35 // 34 //
36 35
37 #include "G4PenelopeGammaConversionModel.hh" 36 #include "G4PenelopeGammaConversionModel.hh"
38 #include "G4PhysicalConstants.hh" <<
39 #include "G4SystemOfUnits.hh" <<
40 #include "G4ParticleDefinition.hh" 37 #include "G4ParticleDefinition.hh"
41 #include "G4MaterialCutsCouple.hh" 38 #include "G4MaterialCutsCouple.hh"
42 #include "G4ProductionCutsTable.hh" 39 #include "G4ProductionCutsTable.hh"
43 #include "G4DynamicParticle.hh" 40 #include "G4DynamicParticle.hh"
44 #include "G4Element.hh" 41 #include "G4Element.hh"
45 #include "G4Gamma.hh" 42 #include "G4Gamma.hh"
46 #include "G4Electron.hh" 43 #include "G4Electron.hh"
47 #include "G4Positron.hh" 44 #include "G4Positron.hh"
48 #include "G4PhysicsFreeVector.hh" << 45 #include "G4CrossSectionHandler.hh"
49 #include "G4MaterialCutsCouple.hh" <<
50 #include "G4AutoLock.hh" <<
51 #include "G4Exp.hh" <<
52 46
53 //....oooOO0OOooo........oooOO0OOooo........oo 47 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
54 const G4int G4PenelopeGammaConversionModel::fM <<
55 G4PhysicsFreeVector* G4PenelopeGammaConversion <<
56 G4double G4PenelopeGammaConversionModel::fAtom <<
57 1.2281e+02,7.3167e+01,6.9 <<
58 6.4696e+01,6.1228e+01,5.7 <<
59 5.0787e+01,4.7851e+01,4.6 <<
60 4.4503e+01,4.3815e+01,4.3 <<
61 4.1586e+01,4.0953e+01,4.0 <<
62 3.9756e+01,3.9144e+01,3.8 <<
63 3.7174e+01,3.6663e+01,3.5 <<
64 3.4688e+01,3.4197e+01,3.3 <<
65 3.3068e+01,3.2740e+01,3.2 <<
66 3.1884e+01,3.1622e+01,3.1 <<
67 3.0950e+01,3.0758e+01,3.0 <<
68 3.0097e+01,2.9832e+01,2.9 <<
69 2.9247e+01,2.9085e+01,2.8 <<
70 2.8580e+01,2.8442e+01,2.8 <<
71 2.7973e+01,2.7819e+01,2.7 <<
72 2.7285e+01,2.7093e+01,2.6 <<
73 2.6516e+01,2.6304e+01,2.6 <<
74 2.5730e+01,2.5577e+01,2.5 <<
75 2.5100e+01,2.4941e+01,2.4 <<
76 2.4506e+01,2.4391e+01,2.4 <<
77 2.4039e+01,2.3922e+01,2.3 <<
78 2.3621e+01,2.3523e+01,2.3 <<
79 2.3238e+01,2.3139e+01,2.3 <<
80 2.2833e+01,2.2694e+01,2.2 <<
81 2.2446e+01,2.2358e+01,2.2 <<
82 48
83 //....oooOO0OOooo........oooOO0OOooo........oo <<
84 49
85 G4PenelopeGammaConversionModel::G4PenelopeGamm << 50 G4PenelopeGammaConversionModel::G4PenelopeGammaConversionModel(const G4ParticleDefinition*,
86 const G4String& nam) << 51 const G4String& nam)
87 :G4VEmModel(nam),fParticleChange(nullptr),fP << 52 :G4VEmModel(nam),fTheScreeningRadii(0),crossSectionHandler(0),isInitialised(false)
88 fEffectiveCharge(nullptr),fMaterialInvScree <<
89 fScreeningFunction(nullptr),fIsInitialised( <<
90 { 53 {
91 fIntrinsicLowEnergyLimit = 2.0*electron_mass 54 fIntrinsicLowEnergyLimit = 2.0*electron_mass_c2;
92 fIntrinsicHighEnergyLimit = 100.0*GeV; 55 fIntrinsicHighEnergyLimit = 100.0*GeV;
93 fSmallEnergy = 1.1*MeV; 56 fSmallEnergy = 1.1*MeV;
94 57
95 if (part) << 58 SetLowEnergyLimit(fIntrinsicLowEnergyLimit);
96 SetParticle(part); <<
97 <<
98 // SetLowEnergyLimit(fIntrinsicLowEnergyLim <<
99 SetHighEnergyLimit(fIntrinsicHighEnergyLimit 59 SetHighEnergyLimit(fIntrinsicHighEnergyLimit);
100 // 60 //
101 fVerboseLevel= 0; << 61 verboseLevel= 0;
102 // Verbosity scale: 62 // Verbosity scale:
103 // 0 = nothing << 63 // 0 = nothing
104 // 1 = warning for energy non-conservation << 64 // 1 = warning for energy non-conservation
105 // 2 = details of energy budget 65 // 2 = details of energy budget
106 // 3 = calculation of cross sections, file o 66 // 3 = calculation of cross sections, file openings, sampling of atoms
107 // 4 = entering in methods 67 // 4 = entering in methods
108 } 68 }
109 69
110 //....oooOO0OOooo........oooOO0OOooo........oo 70 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
111 71
112 G4PenelopeGammaConversionModel::~G4PenelopeGam 72 G4PenelopeGammaConversionModel::~G4PenelopeGammaConversionModel()
113 { << 73 {
114 //Delete shared tables, they exist only in t << 74 if (crossSectionHandler) delete crossSectionHandler;
115 if (IsMaster() || fLocalTable) << 75 if (fTheScreeningRadii) delete fTheScreeningRadii;
116 { <<
117 for(G4int i=0; i<=fMaxZ; ++i) <<
118 { <<
119 if(fLogAtomicCrossSection[i]) { <<
120 delete fLogAtomicCrossSection[i]; <<
121 fLogAtomicCrossSection[i] = nullptr; <<
122 } <<
123 } <<
124 if (fEffectiveCharge) <<
125 delete fEffectiveCharge; <<
126 if (fMaterialInvScreeningRadius) <<
127 delete fMaterialInvScreeningRadius; <<
128 if (fScreeningFunction) <<
129 delete fScreeningFunction; <<
130 } <<
131 } 76 }
132 77
133 //....oooOO0OOooo........oooOO0OOooo........oo 78 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
134 79
135 void G4PenelopeGammaConversionModel::Initialis << 80 void G4PenelopeGammaConversionModel::Initialise(const G4ParticleDefinition*,
136 const G4DataVector&) << 81 const G4DataVector& )
137 { 82 {
138 if (fVerboseLevel > 3) << 83 if (verboseLevel > 3)
139 G4cout << "Calling G4PenelopeGammaConvers 84 G4cout << "Calling G4PenelopeGammaConversionModel::Initialise()" << G4endl;
140 85
141 SetParticle(part); << 86 //Delete the old cross section handler, if necessary
142 << 87 if (crossSectionHandler)
143 //Only the master model creates/fills/destro <<
144 if (IsMaster() && part == fParticle) <<
145 { 88 {
146 //delete old material data... << 89 crossSectionHandler->Clear();
147 if (fEffectiveCharge) << 90 delete crossSectionHandler;
148 { << 91 }
149 delete fEffectiveCharge; << 92
150 fEffectiveCharge = nullptr; << 93 //Check energy limits
151 } << 94 if (LowEnergyLimit() < fIntrinsicLowEnergyLimit)
152 if (fMaterialInvScreeningRadius) << 95 {
153 { << 96 G4cout << "G4PenelopeGammaConversionModel: low energy limit increased from " <<
154 delete fMaterialInvScreeningRadius; << 97 LowEnergyLimit()/eV << " eV to " << fIntrinsicLowEnergyLimit/eV << " eV" << G4endl;
155 fMaterialInvScreeningRadius = nullptr; << 98 SetLowEnergyLimit(fIntrinsicLowEnergyLimit);
156 } << 99 }
157 if (fScreeningFunction) << 100 if (HighEnergyLimit() > fIntrinsicHighEnergyLimit)
158 { << 101 {
159 delete fScreeningFunction; << 102 G4cout << "G4PenelopeGammaConversionModel: high energy limit decreased from " <<
160 fScreeningFunction = nullptr; << 103 HighEnergyLimit()/GeV << " GeV to " << fIntrinsicHighEnergyLimit/GeV << " GeV" << G4endl;
161 } << 104 SetHighEnergyLimit(fIntrinsicHighEnergyLimit);
162 //and create new ones <<
163 fEffectiveCharge = new std::map<const G4 <<
164 fMaterialInvScreeningRadius = new std::m <<
165 fScreeningFunction = new std::map<const <<
166 <<
167 G4ProductionCutsTable* theCoupleTable = <<
168 G4ProductionCutsTable::GetProductionCutsTabl <<
169 <<
170 for (G4int i=0;i<(G4int)theCoupleTable-> <<
171 { <<
172 const G4Material* material = <<
173 theCoupleTable->GetMaterialCutsCouple(i) <<
174 const G4ElementVector* theElementVector = <<
175 <<
176 for (std::size_t j=0;j<material->GetNumber <<
177 { <<
178 G4int iZ = theElementVector->at(j)->Ge <<
179 //read data files only in the master <<
180 if (iZ <= fMaxZ && !fLogAtomicCrossSe <<
181 ReadDataFile(iZ); <<
182 } <<
183 <<
184 //check if material data are available <<
185 if (!fEffectiveCharge->count(material)) <<
186 InitializeScreeningFunctions(material); <<
187 } <<
188 if (fVerboseLevel > 0) { <<
189 G4cout << "Penelope Gamma Conversion model v <<
190 << "Energy range: " <<
191 << LowEnergyLimit() / MeV << " MeV - <<
192 << HighEnergyLimit() / GeV << " GeV" <<
193 << G4endl; <<
194 } <<
195 } 105 }
196 if(fIsInitialised) return; <<
197 fParticleChange = GetParticleChangeForGamma( <<
198 fIsInitialised = true; <<
199 } <<
200 106
201 //....oooOO0OOooo........oooOO0OOooo........oo << 107 //Re-initialize cross section handler
>> 108 crossSectionHandler = new G4CrossSectionHandler();
>> 109 crossSectionHandler->Initialise(0,LowEnergyLimit(),HighEnergyLimit(),400);
>> 110 crossSectionHandler->Clear();
>> 111 G4String crossSectionFile = "penelope/pp-cs-pen-";
>> 112 crossSectionHandler->LoadData(crossSectionFile);
>> 113 //This is used to retrieve cross section values later on
>> 114 crossSectionHandler->BuildMeanFreePathForMaterials();
202 115
203 void G4PenelopeGammaConversionModel::Initialis << 116 if (verboseLevel > 2)
204 G4VEmModel *masterModel) << 117 G4cout << "Loaded cross section files for PenelopeGammaConversion" << G4endl;
205 { <<
206 if (fVerboseLevel > 3) <<
207 G4cout << "Calling G4PenelopeGammaConvers <<
208 // <<
209 //Check that particle matches: one might hav <<
210 //for e+ and e-). <<
211 // <<
212 if (part == fParticle) <<
213 { <<
214 //Get the const table pointers from the <<
215 const G4PenelopeGammaConversionModel* th <<
216 static_cast<G4PenelopeGammaConversionModel*> <<
217 118
218 //Copy pointers to the data tables << 119 G4cout << "Penelope Gamma Conversion model is initialized " << G4endl
219 fEffectiveCharge = theModel->fEffectiveC << 120 << "Energy range: "
220 fMaterialInvScreeningRadius = theModel-> << 121 << LowEnergyLimit() / MeV << " MeV - "
221 fScreeningFunction = theModel->fScreenin << 122 << HighEnergyLimit() / GeV << " GeV"
222 for(G4int i=0; i<=fMaxZ; ++i) << 123 << G4endl;
223 fLogAtomicCrossSection[i] = theModel->fLogAt <<
224 124
225 //Same verbosity for all workers, as the << 125 if(isInitialised) return;
226 fVerboseLevel = theModel->fVerboseLevel; <<
227 } <<
228 126
229 return; << 127 if(pParticleChange)
>> 128 fParticleChange = reinterpret_cast<G4ParticleChangeForGamma*>(pParticleChange);
>> 129 else
>> 130 fParticleChange = new G4ParticleChangeForGamma();
>> 131 isInitialised = true;
230 } 132 }
231 133
232 //....oooOO0OOooo........oooOO0OOooo........oo 134 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
233 namespace { G4Mutex PenelopeGammaConversionMo <<
234 135
235 G4double G4PenelopeGammaConversionModel::Compu 136 G4double G4PenelopeGammaConversionModel::ComputeCrossSectionPerAtom(
236 const G4ParticleDefinition << 137 const G4ParticleDefinition*,
237 G4double energy, << 138 G4double energy,
238 G4double Z, G4double, << 139 G4double Z, G4double,
239 G4double, G4double) << 140 G4double, G4double)
240 { 141 {
241 // 142 //
242 // Penelope model v2008. << 143 // Penelope model.
243 // Cross section (including triplet producti << 144 // Cross section (including triplet production) read from database and managed
244 // through the G4CrossSectionHandler utility 145 // through the G4CrossSectionHandler utility. Cross section data are from
245 // M.J. Berger and J.H. Hubbel (XCOM), Repor 146 // M.J. Berger and J.H. Hubbel (XCOM), Report NBSIR 887-3598
246 // 147 //
>> 148
>> 149 if (verboseLevel > 3)
>> 150 G4cout << "Calling ComputeCrossSectionPerAtom() of G4PenelopePhotoElectricModel" << G4endl;
247 151
248 if (energy < fIntrinsicLowEnergyLimit) << 152 G4int iZ = (G4int) Z;
249 return 0; << 153 if (!crossSectionHandler)
250 << 154 {
251 G4int iZ = G4int(Z); << 155 G4cout << "G4PenelopeGammaConversionModel::ComputeCrossSectionPerAtom" << G4endl;
252 << 156 G4cout << "The cross section handler is not correctly initialized" << G4endl;
253 if (!fLogAtomicCrossSection[iZ]) << 157 G4Exception();
254 { << 158 }
255 //If we are here, it means that Initial << 159 G4double cs = crossSectionHandler->FindValue(iZ,energy);
256 //not filled up. This can happen in a U <<
257 if (fVerboseLevel > 0) <<
258 { <<
259 //Issue a G4Exception (warning) only in v <<
260 G4ExceptionDescription ed; <<
261 ed << "Unable to retrieve the cross secti <<
262 ed << "This can happen only in Unit Tests <<
263 G4Exception("G4PenelopeGammaConversionMod <<
264 "em2018",JustWarning,ed); <<
265 } <<
266 //protect file reading via autolock <<
267 G4AutoLock lock(&PenelopeGammaConversio <<
268 ReadDataFile(iZ); <<
269 lock.unlock(); <<
270 fLocalTable = true; <<
271 } <<
272 G4double cs = 0; <<
273 G4double logene = G4Log(energy); <<
274 G4PhysicsFreeVector* theVec = fLogAtomicCros <<
275 G4double logXS = theVec->Value(logene); <<
276 cs = G4Exp(logXS); <<
277 160
278 if (fVerboseLevel > 2) << 161 if (verboseLevel > 2)
279 G4cout << "Gamma conversion cross section << 162 G4cout << "Gamma conversion cross section at " << energy/MeV << " MeV for Z=" << Z <<
280 " = " << cs/barn << " barn" << G4endl; 163 " = " << cs/barn << " barn" << G4endl;
281 return cs; 164 return cs;
282 } 165 }
283 166
284 //....oooOO0OOooo........oooOO0OOooo........oo 167 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
285 168
286 void << 169 void G4PenelopeGammaConversionModel::SampleSecondaries(std::vector<G4DynamicParticle*>* fvect,
287 G4PenelopeGammaConversionModel::SampleSecondar << 170 const G4MaterialCutsCouple* couple,
288 const G4MaterialCutsCouple* coup << 171 const G4DynamicParticle* aDynamicGamma,
289 const G4DynamicParticle* aDynami << 172 G4double,
290 G4double, << 173 G4double)
291 G4double) <<
292 { 174 {
293 // 175 //
294 // Penelope model v2008. << 176 // Penelope model.
295 // Final state is sampled according to the B 177 // Final state is sampled according to the Bethe-Heitler model with Coulomb
296 // corrections, according to the semi-empiri 178 // corrections, according to the semi-empirical model of
297 // J. Baro' et al., Radiat. Phys. Chem. 44 179 // J. Baro' et al., Radiat. Phys. Chem. 44 (1994) 531.
298 // 180 //
299 // The model uses the high energy Coulomb co << 181 // The model uses the high energy Coulomb correction from
300 // H. Davies et al., Phys. Rev. 93 (1954) 7 182 // H. Davies et al., Phys. Rev. 93 (1954) 788
301 // and atomic screening radii tabulated from << 183 // and atomic screening radii tabulated from
302 // J.H. Hubbel et al., J. Phys. Chem. Ref. 184 // J.H. Hubbel et al., J. Phys. Chem. Ref. Data 9 (1980) 1023
303 // for Z= 1 to 92. << 185 // for Z= 1 to 92. This managed in this model by the method
>> 186 // GetScreeningRadius().
304 // 187 //
305 if (fVerboseLevel > 3) << 188 if (verboseLevel > 3)
306 G4cout << "Calling SamplingSecondaries() o 189 G4cout << "Calling SamplingSecondaries() of G4PenelopeGammaConversionModel" << G4endl;
307 190
308 G4double photonEnergy = aDynamicGamma->GetKi 191 G4double photonEnergy = aDynamicGamma->GetKineticEnergy();
309 192
310 // Always kill primary << 193 if (photonEnergy <= LowEnergyLimit())
311 fParticleChange->ProposeTrackStatus(fStopAnd << 194 {
312 fParticleChange->SetProposedKineticEnergy(0. << 195 fParticleChange->ProposeTrackStatus(fStopAndKill);
313 << 196 fParticleChange->SetProposedKineticEnergy(0.);
314 if (photonEnergy <= fIntrinsicLowEnergyLimit <<
315 { <<
316 fParticleChange->ProposeLocalEnergyDepos 197 fParticleChange->ProposeLocalEnergyDeposit(photonEnergy);
317 return ; 198 return ;
318 } << 199 }
319 200
320 G4ParticleMomentum photonDirection = aDynami 201 G4ParticleMomentum photonDirection = aDynamicGamma->GetMomentumDirection();
321 const G4Material* mat = couple->GetMaterial( <<
322 202
323 //Either Initialize() was not called, or we << 203 G4double eps ;
324 //not invoked << 204 G4double eki = electron_mass_c2 / photonEnergy ;
325 if (!fEffectiveCharge) <<
326 { <<
327 //create a **thread-local** version of t <<
328 //Unit Tests <<
329 fLocalTable = true; <<
330 fEffectiveCharge = new std::map<const G4 <<
331 fMaterialInvScreeningRadius = new std::m <<
332 fScreeningFunction = new std::map<const <<
333 } <<
334 205
335 if (!fEffectiveCharge->count(mat)) << 206 // Do it fast if photon energy < 1.1 MeV
>> 207 if (photonEnergy < fSmallEnergy )
336 { 208 {
337 //If we are here, it means that Initiali << 209 eps = eki + (1-2*eki) * G4UniformRand();
338 //not filled up. This can happen in a Un <<
339 if (fVerboseLevel > 0) <<
340 { <<
341 //Issue a G4Exception (warning) only in ve <<
342 G4ExceptionDescription ed; <<
343 ed << "Unable to allocate the EffectiveCha <<
344 mat->GetName() << G4endl; <<
345 ed << "This can happen only in Unit Tests" <<
346 G4Exception("G4PenelopeGammaConversionMode <<
347 "em2019",JustWarning,ed); <<
348 } <<
349 //protect file reading via autolock <<
350 G4AutoLock lock(&PenelopeGammaConversion <<
351 InitializeScreeningFunctions(mat); <<
352 lock.unlock(); <<
353 } 210 }
354 <<
355 // eps is the fraction of the photon energy <<
356 G4double eps = 0; <<
357 G4double eki = electron_mass_c2/photonEnergy <<
358 <<
359 //Do it fast for photon energy < 1.1 MeV (cl <<
360 if (photonEnergy < fSmallEnergy) <<
361 eps = eki + (1.0-2.0*eki)*G4UniformRand(); <<
362 else 211 else
363 { 212 {
364 //Complete calculation << 213 // Select randomly one element in the current material
365 G4double effC = fEffectiveCharge->find(m << 214 if (verboseLevel > 2)
366 G4double alz = effC*fine_structure_const << 215 G4cout << "Going to select element in " << couple->GetMaterial()->GetName() << G4endl;
367 G4double T = std::sqrt(2.0*eki); << 216 //use crossSectionHandler instead of G4EmElementSelector because in this case
368 G4double F00=(-1.774-1.210e1*alz+1.118e1 << 217 //the dimension of the table is equal to the dimension of the database
369 +(8.523+7.326e1*alz-4.441e1*alz*alz)* << 218 //(less interpolation errors)
370 -(1.352e1+1.211e2*alz-9.641e1*alz*alz << 219 G4int Z_int = crossSectionHandler->SelectRandomAtom(couple,photonEnergy);
371 +(8.946+6.205e1*alz-6.341e1*alz*alz)*T*T*T*T << 220 if (verboseLevel > 2)
372 << 221 G4cout << "Selected Z = " << Z_int << G4endl;
373 G4double F0b = fScreeningFunction->find( << 222
374 G4double g0 = F0b + F00; << 223 //Low energy and Coulomb corrections
375 G4double invRad = fMaterialInvScreeningR << 224 G4double Z=(G4double) Z_int;
376 G4double bmin = 4.0*eki/invRad; << 225 G4double ZAlpha = Z*fine_structure_const;
377 std::pair<G4double,G4double> scree = Ge << 226 G4double ScreenRadius = GetScreeningRadius(Z);
378 G4double g1 = scree.first; << 227 G4double funct1=0,g0=0;
379 G4double g2 = scree.second; << 228 G4double g1min=0,g2min=0;
380 G4double g1min = g1+g0; << 229 funct1 = 4.0*std::log(ScreenRadius);
381 G4double g2min = g2+g0; << 230 g0 = funct1-4*CoulombCorrection(ZAlpha)+LowEnergyCorrection(ZAlpha,eki);
382 G4double xr = 0.5-eki; << 231 G4double bmin = 2*eki*ScreenRadius;
383 G4double a1 = 2.*g1min*xr*xr/3.; << 232 std::vector<G4double> ScreenFunctionValues = ScreenFunction(bmin);
384 G4double p1 = a1/(a1+g2min); << 233 if (ScreenFunctionValues.size() != 2)
>> 234 {
>> 235 G4cout << "G4PenelopeGammaConversionModel::SampleSecondaries" << G4endl;
>> 236 G4cout << "ScreenFunction did not return 2 values! Something wrong! " << G4endl;
>> 237 G4Exception();
>> 238 }
>> 239 g1min=g0+ScreenFunctionValues[0];
>> 240 g2min=g0+ScreenFunctionValues[1];
>> 241 G4double xr,a1,p1;
>> 242 xr=0.5-eki;
>> 243 a1=(2.0/3.0)*g1min*xr*xr;
>> 244 p1=a1/(a1+g2min);
385 245
386 G4bool loopAgain = false; <<
387 //Random sampling of eps 246 //Random sampling of eps
>> 247 G4double rand1,rand2,rand3,b;
>> 248 G4double g1;
>> 249
388 do{ 250 do{
389 loopAgain = false; << 251 rand1 = G4UniformRand();
390 if (G4UniformRand() <= p1) << 252 if (rand1 < p1) {
391 { << 253 rand2 = 2.0*G4UniformRand()-1.0;
392 G4double ru2m1 = 2.0*G4UniformRand()-1. << 254 if (rand2 < 0) {
393 if (ru2m1 < 0) << 255 eps = 0.5 - xr*std::pow(std::abs(rand2),(1./3.));
394 eps = 0.5-xr*std::pow(std::abs(ru2m1), <<
395 else <<
396 eps = 0.5+xr*std::pow(ru2m1,1./3.); <<
397 G4double B = eki/(invRad*eps*(1.0-eps)); <<
398 scree = GetScreeningFunctions(B); <<
399 g1 = scree.first; <<
400 g1 = std::max(g1+g0,0.); <<
401 if (G4UniformRand()*g1min > g1) <<
402 loopAgain = true; <<
403 } 256 }
404 else << 257 else
>> 258 {
>> 259 eps = 0.5 + xr*std::pow(rand2,(1./3.));
>> 260 }
>> 261 b = (eki*ScreenRadius)/(2*eps*(1.0-eps));
>> 262 std::vector<G4double> ScreenFunctionSampling = ScreenFunction(b);
>> 263 g1 = g0+ScreenFunctionSampling[0];
>> 264 if (g1 < 0) g1=0;
>> 265 rand3 = G4UniformRand()*g1min;
>> 266 }
>> 267 else
405 { 268 {
406 eps = eki+2.0*xr*G4UniformRand(); 269 eps = eki+2.0*xr*G4UniformRand();
407 G4double B = eki/(invRad*eps*(1.0-eps)); << 270 b = (eki*ScreenRadius)/(2*eps*(1.0-eps));
408 scree = GetScreeningFunctions(B); << 271 std::vector<G4double> ScreenFunctionSampling = ScreenFunction(b);
409 g2 = scree.second; << 272 g1 = g0+ScreenFunctionSampling[1];
410 g2 = std::max(g2+g0,0.); << 273 if (g1 < 0) g1=0;
411 if (G4UniformRand()*g2min > g2) << 274 rand3 = G4UniformRand()*g2min;
412 loopAgain = true; << 275 }
413 } << 276 } while (rand3>g1);
414 }while(loopAgain); << 277 } //End of eps sampling
415 } <<
416 if (fVerboseLevel > 4) <<
417 G4cout << "Sampled eps = " << eps << G4end <<
418 278
419 G4double electronTotEnergy = eps*photonEnerg 279 G4double electronTotEnergy = eps*photonEnergy;
420 G4double positronTotEnergy = (1.0-eps)*photo 280 G4double positronTotEnergy = (1.0-eps)*photonEnergy;
421 << 281
422 // Scattered electron (positron) angles. ( Z 282 // Scattered electron (positron) angles. ( Z - axis along the parent photon)
423 283
424 //electron kinematics 284 //electron kinematics
425 G4double electronKineEnergy = std::max(0.,el << 285 G4double costheta_el,costheta_po;
426 G4double costheta_el = G4UniformRand()*2.0-1 << 286 G4double phi_el,phi_po;
>> 287 G4double electronKineEnergy = std::max(0.,electronTotEnergy - electron_mass_c2) ;
>> 288 costheta_el = G4UniformRand()*2.0-1.0;
427 G4double kk = std::sqrt(electronKineEnergy*( 289 G4double kk = std::sqrt(electronKineEnergy*(electronKineEnergy+2.*electron_mass_c2));
428 costheta_el = (costheta_el*electronTotEnergy 290 costheta_el = (costheta_el*electronTotEnergy+kk)/(electronTotEnergy+costheta_el*kk);
429 G4double phi_el = twopi * G4UniformRand() ; << 291 phi_el = twopi * G4UniformRand() ;
430 G4double dirX_el = std::sqrt(1.-costheta_el* 292 G4double dirX_el = std::sqrt(1.-costheta_el*costheta_el) * std::cos(phi_el);
431 G4double dirY_el = std::sqrt(1.-costheta_el* 293 G4double dirY_el = std::sqrt(1.-costheta_el*costheta_el) * std::sin(phi_el);
432 G4double dirZ_el = costheta_el; 294 G4double dirZ_el = costheta_el;
433 295
434 //positron kinematics 296 //positron kinematics
435 G4double positronKineEnergy = std::max(0.,po 297 G4double positronKineEnergy = std::max(0.,positronTotEnergy - electron_mass_c2) ;
436 G4double costheta_po = G4UniformRand()*2.0-1 << 298 costheta_po = G4UniformRand()*2.0-1.0;
437 kk = std::sqrt(positronKineEnergy*(positronK 299 kk = std::sqrt(positronKineEnergy*(positronKineEnergy+2.*electron_mass_c2));
438 costheta_po = (costheta_po*positronTotEnergy 300 costheta_po = (costheta_po*positronTotEnergy+kk)/(positronTotEnergy+costheta_po*kk);
439 G4double phi_po = twopi * G4UniformRand() ; << 301 phi_po = twopi * G4UniformRand() ;
440 G4double dirX_po = std::sqrt(1.-costheta_po* 302 G4double dirX_po = std::sqrt(1.-costheta_po*costheta_po) * std::cos(phi_po);
441 G4double dirY_po = std::sqrt(1.-costheta_po* 303 G4double dirY_po = std::sqrt(1.-costheta_po*costheta_po) * std::sin(phi_po);
442 G4double dirZ_po = costheta_po; 304 G4double dirZ_po = costheta_po;
443 305
444 // Kinematics of the created pair: 306 // Kinematics of the created pair:
445 // the electron and positron are assumed to 307 // the electron and positron are assumed to have a symetric angular
446 // distribution with respect to the Z axis a 308 // distribution with respect to the Z axis along the parent photon
447 G4double localEnergyDeposit = 0. ; 309 G4double localEnergyDeposit = 0. ;
448 310
449 if (electronKineEnergy > 0.0) << 311 //Generate explicitely the electron in the pair, only if it is > threshold
>> 312 const G4ProductionCutsTable* theCoupleTable=
>> 313 G4ProductionCutsTable::GetProductionCutsTable();
>> 314 size_t indx = couple->GetIndex();
>> 315 G4double cutE = (*(theCoupleTable->GetEnergyCutsVector(1)))[indx];
>> 316 //G4double cutP = (*(theCoupleTable->GetEnergyCutsVector(2)))[indx];
>> 317
>> 318 if (electronKineEnergy > cutE)
450 { 319 {
451 G4ThreeVector electronDirection ( dirX_e 320 G4ThreeVector electronDirection ( dirX_el, dirY_el, dirZ_el);
452 electronDirection.rotateUz(photonDirecti 321 electronDirection.rotateUz(photonDirection);
453 G4DynamicParticle* electron = new G4Dyna 322 G4DynamicParticle* electron = new G4DynamicParticle (G4Electron::Electron(),
454 electronDirection, 323 electronDirection,
455 electronKineEnergy); 324 electronKineEnergy);
456 fvect->push_back(electron); 325 fvect->push_back(electron);
457 } 326 }
458 else 327 else
459 { 328 {
460 localEnergyDeposit += electronKineEnergy 329 localEnergyDeposit += electronKineEnergy;
461 electronKineEnergy = 0; 330 electronKineEnergy = 0;
462 } 331 }
463 332
464 //Generate the positron. Real particle in an 333 //Generate the positron. Real particle in any case, because it will annihilate. If below
465 //threshold, produce it at rest 334 //threshold, produce it at rest
466 if (positronKineEnergy < 0.0) << 335 if (positronKineEnergy < cutE)
467 { 336 {
468 localEnergyDeposit += positronKineEnergy 337 localEnergyDeposit += positronKineEnergy;
469 positronKineEnergy = 0; //produce it at 338 positronKineEnergy = 0; //produce it at rest
470 } 339 }
471 G4ThreeVector positronDirection(dirX_po,dirY 340 G4ThreeVector positronDirection(dirX_po,dirY_po,dirZ_po);
472 positronDirection.rotateUz(photonDirection); 341 positronDirection.rotateUz(photonDirection);
473 G4DynamicParticle* positron = new G4DynamicP 342 G4DynamicParticle* positron = new G4DynamicParticle(G4Positron::Positron(),
474 positronDirection, positronK 343 positronDirection, positronKineEnergy);
475 fvect->push_back(positron); 344 fvect->push_back(positron);
476 345
477 //Add rest of energy to the local energy dep << 346 //Update the status of the primary gamma (kill it)
>> 347 fParticleChange->SetProposedKineticEnergy(0.);
478 fParticleChange->ProposeLocalEnergyDeposit(l 348 fParticleChange->ProposeLocalEnergyDeposit(localEnergyDeposit);
>> 349 fParticleChange->ProposeTrackStatus(fStopAndKill);
479 350
480 if (fVerboseLevel > 1) << 351
>> 352 if (verboseLevel > 1)
481 { 353 {
482 G4cout << "----------------------------- 354 G4cout << "-----------------------------------------------------------" << G4endl;
483 G4cout << "Energy balance from G4Penelop 355 G4cout << "Energy balance from G4PenelopeGammaConversion" << G4endl;
484 G4cout << "Incoming photon energy: " << 356 G4cout << "Incoming photon energy: " << photonEnergy/keV << " keV" << G4endl;
485 G4cout << "----------------------------- 357 G4cout << "-----------------------------------------------------------" << G4endl;
486 if (electronKineEnergy) 358 if (electronKineEnergy)
487 G4cout << "Electron (explicitly produced) " << 359 G4cout << "Electron (explicitely produced) " << electronKineEnergy/keV << " keV" << G4endl;
488 << G4endl; <<
489 if (positronKineEnergy) 360 if (positronKineEnergy)
490 G4cout << "Positron (not at rest) " << posit 361 G4cout << "Positron (not at rest) " << positronKineEnergy/keV << " keV" << G4endl;
491 G4cout << "Rest masses of e+/- " << 2.0* 362 G4cout << "Rest masses of e+/- " << 2.0*electron_mass_c2/keV << " keV" << G4endl;
492 if (localEnergyDeposit) 363 if (localEnergyDeposit)
493 G4cout << "Local energy deposit " << localEn 364 G4cout << "Local energy deposit " << localEnergyDeposit/keV << " keV" << G4endl;
494 G4cout << "Total final state: " << (elec 365 G4cout << "Total final state: " << (electronKineEnergy+positronKineEnergy+
495 localEnergyDeposit+2.0*electron_ma 366 localEnergyDeposit+2.0*electron_mass_c2)/keV <<
496 " keV" << G4endl; 367 " keV" << G4endl;
497 G4cout << "----------------------------- 368 G4cout << "-----------------------------------------------------------" << G4endl;
498 } 369 }
499 if (fVerboseLevel > 0) << 370 if (verboseLevel > 0)
500 { 371 {
501 G4double energyDiff = std::fabs(electron 372 G4double energyDiff = std::fabs(electronKineEnergy+positronKineEnergy+
502 localEnergyDeposit+2.0*electron_ 373 localEnergyDeposit+2.0*electron_mass_c2-photonEnergy);
503 if (energyDiff > 0.05*keV) 374 if (energyDiff > 0.05*keV)
504 G4cout << "Warning from G4PenelopeGammaConve << 375 G4cout << "Warning from G4PenelopeGammaConversion: problem with energy conservation: " <<
505 << (electronKineEnergy+positronKineEn << 376 (electronKineEnergy+positronKineEnergy+
506 localEnergyDeposit+2.0*electron_mass_c2 << 377 localEnergyDeposit+2.0*electron_mass_c2)/keV << " keV (final) vs. " <<
507 << " keV (final) vs. " << photonEnerg << 378 photonEnergy/keV << " keV (initial)" << G4endl;
508 } 379 }
>> 380
509 } 381 }
510 382
511 //....oooOO0OOooo........oooOO0OOooo........oo 383 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
512 384
513 void G4PenelopeGammaConversionModel::ReadDataF << 385 std::vector<G4double> G4PenelopeGammaConversionModel::ScreenFunction(G4double b)
514 { 386 {
515 if (!IsMaster()) << 387 std::vector<G4double> result;
516 //Should not be here! << 388 result.clear();
517 G4Exception("G4PenelopeGammaConversionMode << 389 G4double bsquare=b*b;
518 "em0100",FatalException,"Worker thread in << 390 G4double a0,f1,f2;
519 << 391 f1=2.0-2*std::log(1+bsquare);
520 if (fVerboseLevel > 2) << 392 f2=f1-(2.0/3.0);
521 { << 393 if (b < 1.0e-10)
522 G4cout << "G4PenelopeGammaConversionMode <<
523 G4cout << "Going to read Gamma Conversio <<
524 } <<
525 <<
526 const char* path = G4FindDataDir("G4LEDATA <<
527 if(!path) <<
528 { 394 {
529 G4String excep = << 395 f1=f1-twopi*b;
530 "G4PenelopeGammaConversionModel - G4LEDATA e <<
531 G4Exception("G4PenelopeGammaConversionMo <<
532 "em0006",FatalException,excep); <<
533 return; <<
534 } 396 }
535 <<
536 /* <<
537 Read the cross section file <<
538 */ <<
539 std::ostringstream ost; <<
540 if (Z>9) <<
541 ost << path << "/penelope/pairproduction/p <<
542 else 397 else
543 ost << path << "/penelope/pairproduction/p << 398 {
544 std::ifstream file(ost.str().c_str()); << 399 a0 = 4*b*std::atan(1.0/b);
545 if (!file.is_open()) << 400 f1 = f1 - a0;
546 { << 401 f2 = f2+2*bsquare*(4.0-a0-3*std::log((1+bsquare)/bsquare));
547 G4String excep = "G4PenelopeGammaConvers <<
548 G4String(ost.str()) + " not found!"; <<
549 G4Exception("G4PenelopeGammaConversionMo <<
550 "em0003",FatalException,excep); <<
551 } <<
552 <<
553 //I have to know in advance how many points <<
554 //to initialize the G4PhysicsFreeVector() <<
555 std::size_t ndata=0; <<
556 G4String line; <<
557 while( getline(file, line) ) <<
558 ndata++; <<
559 ndata -= 1; //remove one header line <<
560 <<
561 file.clear(); <<
562 file.close(); <<
563 file.open(ost.str().c_str()); <<
564 G4int readZ =0; <<
565 file >> readZ; <<
566 <<
567 if (fVerboseLevel > 3) <<
568 G4cout << "Element Z=" << Z << G4endl; <<
569 <<
570 //check the right file is opened. <<
571 if (readZ != Z) <<
572 { <<
573 G4ExceptionDescription ed; <<
574 ed << "Corrupted data file for Z=" << Z <<
575 G4Exception("G4PenelopeGammaConversionMo <<
576 "em0005",FatalException,ed); <<
577 } <<
578 <<
579 fLogAtomicCrossSection[Z] = new G4PhysicsFre <<
580 G4double ene=0,xs=0; <<
581 for (std::size_t i=0;i<ndata;++i) <<
582 { <<
583 file >> ene >> xs; <<
584 //dimensional quantities <<
585 ene *= eV; <<
586 xs *= barn; <<
587 if (xs < 1e-40*cm2) //protection against <<
588 xs = 1e-40*cm2; <<
589 fLogAtomicCrossSection[Z]->PutValue(i,G4 <<
590 } 402 }
591 file.close(); << 403 result.push_back(0.5*(3*f1-f2));
592 << 404 result.push_back(0.25*(3*f1+f2));
593 return; << 405 return result;
594 } 406 }
595 407
596 //....oooOO0OOooo........oooOO0OOooo........oo 408 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
597 409
598 void G4PenelopeGammaConversionModel::Initializ << 410 G4double G4PenelopeGammaConversionModel::GetScreeningRadius(G4double Z)
599 { 411 {
600 // This is subroutine GPPa0 of Penelope << 412 G4double result = 0;
601 // << 413 G4bool foundElement = false;
602 // 1) calculate the effective Z for the purp << 414 G4int iZ = (G4int) Z;
603 // << 415 if (!fTheScreeningRadii)
604 G4double zeff = 0; << 416 fTheScreeningRadii = new std::map<G4int,G4double>;
605 G4int intZ = 0; << 417
606 G4int nElements = (G4int)material->GetNumber << 418 if (fTheScreeningRadii->count(iZ))
607 const G4ElementVector* elementVector = mater << 419 {
608 << 420 //The element is already loaded: just return it
609 //avoid calculations if only one building el << 421 result = fTheScreeningRadii->find(iZ)->second;
610 if (nElements == 1) << 422 return result;
611 { <<
612 zeff = (*elementVector)[0]->GetZ(); <<
613 intZ = (G4int) zeff; <<
614 } 423 }
615 else // many elements...let's do the calcula << 424 else //retrieve all from file
616 { 425 {
617 const G4double* fractionVector = materia << 426 char* path = getenv("G4LEDATA");
618 << 427 if (!path)
619 G4double atot = 0; <<
620 for (G4int i=0;i<nElements;i++) <<
621 { 428 {
622 G4double Zelement = (*elementVector)[i]->G << 429 G4String excep = "G4PenelopeGammaConversionModel - G4LEDATA environment variable not set!";
623 G4double Aelement = (*elementVector)[i]->G << 430 G4Exception(excep);
624 atot += Aelement*fractionVector[i]; << 431 }
625 zeff += Zelement*Aelement*fractionVector[i << 432 G4String pathString(path);
>> 433 G4String pathFile = pathString + "/penelope/pp-pen.dat";
>> 434 std::ifstream file(pathFile);
>> 435
>> 436 if (!(file.is_open()))
>> 437 {
>> 438 G4String excep = "G4PenelopeGammaConversionModel - data file " + pathFile + "not found!";
>> 439 G4Exception(excep);
>> 440 }
>> 441 G4int k;
>> 442 G4double a1,a2;
>> 443 while(!file.eof()) {
>> 444 file >> k >> a1 >> a2;
>> 445 fTheScreeningRadii->insert(std::make_pair(k,a1));
>> 446 if ((G4double) k == Z)
>> 447 {
>> 448 result = a1;
>> 449 foundElement = true;
>> 450 }
>> 451 }
>> 452 file.close();
>> 453 if (verboseLevel > 2)
>> 454 G4cout << "Read file pp-pen.dat" << G4endl;
>> 455 if (foundElement)
>> 456 return result;
>> 457 else
>> 458 {
>> 459 G4String excep = "G4PenelopeGammaConversionModel - Screening Radius for not found in the data file";
>> 460 G4Exception(excep);
>> 461 return 0;
626 } 462 }
627 atot /= material->GetTotNbOfAtomsPerVolu <<
628 zeff /= (material->GetTotNbOfAtomsPerVol <<
629 <<
630 intZ = (G4int) (zeff+0.25); <<
631 if (intZ <= 0) <<
632 intZ = 1; <<
633 if (intZ > fMaxZ) <<
634 intZ = fMaxZ; <<
635 } <<
636 <<
637 if (fEffectiveCharge) <<
638 fEffectiveCharge->insert(std::make_pair(ma <<
639 <<
640 // <<
641 // 2) Calculate Coulomb Correction <<
642 // <<
643 G4double alz = fine_structure_const*zeff; <<
644 G4double alzSquared = alz*alz; <<
645 G4double fc = alzSquared*(0.202059-alzSquar <<
646 (0.03693-alzSquared* <<
647 (0.00835-alzSquared*(0.00201-alzSq <<
648 (0.00049-alzSquared* <<
649 (0.00012-alzSquared*0.00003))) <<
650 +1.0/(alzSquared+1.0)); <<
651 // <<
652 // 3) Screening functions and low-energy cor <<
653 // <<
654 G4double matRadius = 2.0/ fAtomicScreeningRa <<
655 if (fMaterialInvScreeningRadius) <<
656 fMaterialInvScreeningRadius->insert(std::m <<
657 <<
658 std::pair<G4double,G4double> myPair(0,0); <<
659 G4double f0a = 4.0*G4Log(fAtomicScreeningRad <<
660 G4double f0b = f0a - 4.0*fc; <<
661 myPair.first = f0a; <<
662 myPair.second = f0b; <<
663 <<
664 if (fScreeningFunction) <<
665 fScreeningFunction->insert(std::make_pair( <<
666 <<
667 if (fVerboseLevel > 2) <<
668 { <<
669 G4cout << "Average Z for material " << m <<
670 zeff << G4endl; <<
671 G4cout << "Effective radius for material <<
672 fAtomicScreeningRadius[intZ] << " m_e*c/hbar <<
673 matRadius << G4endl; <<
674 G4cout << "Screening parameters F0 for m <<
675 f0a << "," << f0b << G4endl; <<
676 } 463 }
677 return; <<
678 } 464 }
679 465
680 //....oooOO0OOooo........oooOO0OOooo........oo 466 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
681 467
682 std::pair<G4double,G4double> << 468 G4double G4PenelopeGammaConversionModel::CoulombCorrection(G4double a)
683 G4PenelopeGammaConversionModel::GetScreeningFu <<
684 { 469 {
685 // This is subroutine SCHIFF of Penelope << 470 G4double fc=0;
686 // << 471 G4double b[7] = {0.202059,-0.03693,0.00835,-0.00201,0.00049,-0.00012,0.00003};
687 // Screening Functions F1(B) and F2(B) in th << 472 G4double aSquared = a*a;
688 // section for pair production << 473 G4double aFourth = aSquared*aSquared;
689 // << 474 G4double aEighth = aFourth*aFourth;
690 std::pair<G4double,G4double> result(0.,0.); << 475
691 G4double BSquared = B*B; << 476 fc = ((1.0/(1.0+a*a))+b[0]+b[1]*aSquared+b[2]*aFourth+b[3]*(aSquared*aFourth)+
692 G4double f1 = 2.0-2.0*G4Log(1.0+BSquared); << 477 b[4]*aEighth+b[5]*(aEighth*aSquared)+b[6]*(aEighth*aFourth));
693 G4double f2 = f1 - 6.66666666e-1; // (-2/3) << 478 fc=aSquared*fc;
694 if (B < 1.0e-10) << 479 return fc;
695 f1 = f1-twopi*B; <<
696 else <<
697 { <<
698 G4double a0 = 4.0*B*std::atan(1./B); <<
699 f1 = f1 - a0; <<
700 f2 += 2.0*BSquared*(4.0-a0-3.0*G4Log((1. <<
701 } <<
702 G4double g1 = 0.5*(3.0*f1-f2); <<
703 G4double g2 = 0.25*(3.0*f1+f2); <<
704 <<
705 result.first = g1; <<
706 result.second = g2; <<
707 <<
708 return result; <<
709 } 480 }
710 481
711 //....oooOO0OOooo........oooOO0OOooo........oo << 482 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
712 483
713 void G4PenelopeGammaConversionModel::SetPartic << 484 G4double G4PenelopeGammaConversionModel::LowEnergyCorrection(G4double a,G4double eki)
714 { 485 {
715 if(!fParticle) { << 486 G4double f0=0,t=0;
716 fParticle = p; << 487 G4double b[12] = {-1.744,-12.10,11.18,8.523,73.26,-41.41,-13.52,-121.1,94.41,8.946,62.05,-63.41};
717 } << 488 t=std::sqrt(2.0*eki);
>> 489 G4double tSq = t*t;
>> 490 f0=(b[0]+b[1]*a+b[2]*a*a)*t+(b[3]+b[4]*a+b[5]*a*a)*(tSq)+(b[6]+b[7]*a+b[8]*a*a)*(tSq*t)+
>> 491 (b[9]+b[10]*a+b[11]*a*a)*(tSq*tSq);
>> 492 return f0;
>> 493
718 } 494 }
719 495