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25 //
26 //
27 //
28 // Author: A. Forti
29 // Maria Grazia Pia (Maria.Grazia.Pia@cern.ch)
30 //
31 // History:
32 // --------
33 // October 1998 - low energy modifications by Alessandra Forti
34 // Added Livermore data table construction methods A. Forti
35 // Modified BuildMeanFreePath to read new data tables A. Forti
36 // Added EnergySampling method A. Forti
37 // Modified PostStepDoIt to insert sampling with EPDL97 data A. Forti
38 // Added SelectRandomAtom A. Forti
39 // Added map of the elements A. Forti
40 // 10.04.2000 VL
41 // - Correcting Fluorescence transition probabilities in order to take into account
42 // non-radiative transitions. No Auger electron simulated yet: energy is locally deposited.
43 // 17.02.2000 Veronique Lefebure
44 // - bugs corrected in fluorescence simulation:
45 // . when final use of binding energy: no photon was ever created
46 // . no Fluorescence was simulated when the photo-electron energy
47 // was below production threshold.
48 //
49 // 07-09-99, if no e- emitted: edep=photon energy, mma
50 // 24.04.01 V.Ivanchenko remove RogueWave
51 // 12.08.2001 MGP Revised according to a design iteration
52 // 16.09.2001 E. Guardincerri Added fluorescence generation
53 // 06.10.2001 MGP Added protection to avoid negative electron energies
54 // when binding energy of selected shell > photon energy
55 // 18.04.2001 V.Ivanchenko Fix problem with low energy gammas from fluorescence
56 // MeanFreePath is calculated by crosSectionHandler directly
57 // 31.05.2002 V.Ivanchenko Add path of Fluo + Auger cuts to AtomicDeexcitation
58 // 14.06.2002 V.Ivanchenko By default do not cheak range of e-
59 // 21.01.2003 V.Ivanchenko Cut per region
60 // 10.05.2004 P.Rodrigues Changes to accommodate new angular generators
61 // 20.01.2006 A.Trindade Changes to accommodate polarized angular generator
62 //
63 // --------------------------------------------------------------
64
65 #include "G4LowEnergyPhotoElectric.hh"
66
67 #include "G4RDVPhotoElectricAngularDistribution.hh"
68 #include "G4RDPhotoElectricAngularGeneratorSimple.hh"
69 #include "G4RDPhotoElectricAngularGeneratorSauterGavrila.hh"
70 #include "G4RDPhotoElectricAngularGeneratorPolarized.hh"
71
72 #include "G4PhysicalConstants.hh"
73 #include "G4SystemOfUnits.hh"
74 #include "G4ParticleDefinition.hh"
75 #include "G4Track.hh"
76 #include "G4Step.hh"
77 #include "G4ForceCondition.hh"
78 #include "G4Gamma.hh"
79 #include "G4Electron.hh"
80 #include "G4DynamicParticle.hh"
81 #include "G4VParticleChange.hh"
82 #include "G4ThreeVector.hh"
83 #include "G4RDVCrossSectionHandler.hh"
84 #include "G4RDCrossSectionHandler.hh"
85 #include "G4RDVEMDataSet.hh"
86 #include "G4RDCompositeEMDataSet.hh"
87 #include "G4RDVDataSetAlgorithm.hh"
88 #include "G4RDLogLogInterpolation.hh"
89 #include "G4RDVRangeTest.hh"
90 #include "G4RDRangeNoTest.hh"
91 #include "G4RDAtomicTransitionManager.hh"
92 #include "G4RDAtomicShell.hh"
93 #include "G4ProductionCutsTable.hh"
94
95 G4LowEnergyPhotoElectric::G4LowEnergyPhotoElectric(const G4String& processName)
96 : G4VDiscreteProcess(processName), lowEnergyLimit(250*eV), highEnergyLimit(100*GeV),
97 intrinsicLowEnergyLimit(10*eV),
98 intrinsicHighEnergyLimit(100*GeV),
99 cutForLowEnergySecondaryPhotons(250.*eV),
100 cutForLowEnergySecondaryElectrons(250.*eV)
101 {
102 if (lowEnergyLimit < intrinsicLowEnergyLimit ||
103 highEnergyLimit > intrinsicHighEnergyLimit)
104 {
105 G4Exception("G4LowEnergyPhotoElectric::G4LowEnergyPhotoElectric()",
106 "OutOfRange", FatalException,
107 "Energy limit outside intrinsic process validity range!");
108 }
109
110 crossSectionHandler = new G4RDCrossSectionHandler();
111 shellCrossSectionHandler = new G4RDCrossSectionHandler();
112 meanFreePathTable = 0;
113 rangeTest = new G4RDRangeNoTest;
114 generatorName = "geant4.6.2";
115 ElectronAngularGenerator = new G4RDPhotoElectricAngularGeneratorSimple("GEANTSimpleGenerator"); // default generator
116
117
118 if (verboseLevel > 0)
119 {
120 G4cout << GetProcessName() << " is created " << G4endl
121 << "Energy range: "
122 << lowEnergyLimit / keV << " keV - "
123 << highEnergyLimit / GeV << " GeV"
124 << G4endl;
125 }
126 }
127
128 G4LowEnergyPhotoElectric::~G4LowEnergyPhotoElectric()
129 {
130 delete crossSectionHandler;
131 delete shellCrossSectionHandler;
132 delete meanFreePathTable;
133 delete rangeTest;
134 delete ElectronAngularGenerator;
135 }
136
137 void G4LowEnergyPhotoElectric::BuildPhysicsTable(const G4ParticleDefinition& )
138 {
139
140 crossSectionHandler->Clear();
141 G4String crossSectionFile = "phot/pe-cs-";
142 crossSectionHandler->LoadData(crossSectionFile);
143
144 shellCrossSectionHandler->Clear();
145 G4String shellCrossSectionFile = "phot/pe-ss-cs-";
146 shellCrossSectionHandler->LoadShellData(shellCrossSectionFile);
147
148 delete meanFreePathTable;
149 meanFreePathTable = crossSectionHandler->BuildMeanFreePathForMaterials();
150 }
151
152 G4VParticleChange* G4LowEnergyPhotoElectric::PostStepDoIt(const G4Track& aTrack,
153 const G4Step& aStep)
154 {
155 // Fluorescence generated according to:
156 // J. Stepanek ,"A program to determine the radiation spectra due to a single atomic
157 // subshell ionisation by a particle or due to deexcitation or decay of radionuclides",
158 // Comp. Phys. Comm. 1206 pp 1-1-9 (1997)
159
160 aParticleChange.Initialize(aTrack);
161
162 const G4DynamicParticle* incidentPhoton = aTrack.GetDynamicParticle();
163 G4double photonEnergy = incidentPhoton->GetKineticEnergy();
164 if (photonEnergy <= lowEnergyLimit)
165 {
166 aParticleChange.ProposeTrackStatus(fStopAndKill);
167 aParticleChange.ProposeEnergy(0.);
168 aParticleChange.ProposeLocalEnergyDeposit(photonEnergy);
169 return G4VDiscreteProcess::PostStepDoIt(aTrack,aStep);
170 }
171
172 G4ThreeVector photonDirection = incidentPhoton->GetMomentumDirection(); // Returns the normalized direction of the momentum
173
174 // Select randomly one element in the current material
175 const G4MaterialCutsCouple* couple = aTrack.GetMaterialCutsCouple();
176 G4int Z = crossSectionHandler->SelectRandomAtom(couple,photonEnergy);
177
178 // Select the ionised shell in the current atom according to shell cross sections
179 size_t shellIndex = shellCrossSectionHandler->SelectRandomShell(Z,photonEnergy);
180
181 // Retrieve the corresponding identifier and binding energy of the selected shell
182 const G4RDAtomicTransitionManager* transitionManager = G4RDAtomicTransitionManager::Instance();
183 const G4RDAtomicShell* shell = transitionManager->Shell(Z,shellIndex);
184 G4double bindingEnergy = shell->BindingEnergy();
185 G4int shellId = shell->ShellId();
186
187 // Create lists of pointers to DynamicParticles (photons and electrons)
188 // (Is the electron vector necessary? To be checked)
189 std::vector<G4DynamicParticle*>* photonVector = 0;
190 std::vector<G4DynamicParticle*> electronVector;
191
192 G4double energyDeposit = 0.0;
193
194 // Primary outcoming electron
195 G4double eKineticEnergy = photonEnergy - bindingEnergy;
196
197 // There may be cases where the binding energy of the selected shell is > photon energy
198 // In such cases do not generate secondaries
199 if (eKineticEnergy > 0.)
200 {
201 // Generate the electron only if with large enough range w.r.t. cuts and safety
202 G4double safety = aStep.GetPostStepPoint()->GetSafety();
203
204 if (rangeTest->Escape(G4Electron::Electron(),couple,eKineticEnergy,safety))
205 {
206
207 // Calculate direction of the photoelectron
208 G4ThreeVector gammaPolarization = incidentPhoton->GetPolarization();
209 G4ThreeVector electronDirection = ElectronAngularGenerator->GetPhotoElectronDirection(photonDirection,eKineticEnergy,gammaPolarization,shellId);
210
211 // The electron is created ...
212 G4DynamicParticle* electron = new G4DynamicParticle (G4Electron::Electron(),
213 electronDirection,
214 eKineticEnergy);
215 electronVector.push_back(electron);
216 }
217 else
218 {
219 energyDeposit += eKineticEnergy;
220 }
221 }
222 else
223 {
224 bindingEnergy = photonEnergy;
225 }
226
227 G4int nElectrons = electronVector.size();
228 size_t nTotPhotons = 0;
229 G4int nPhotons=0;
230 const G4ProductionCutsTable* theCoupleTable=
231 G4ProductionCutsTable::GetProductionCutsTable();
232
233 size_t index = couple->GetIndex();
234 G4double cutg = (*(theCoupleTable->GetEnergyCutsVector(0)))[index];
235 cutg = std::min(cutForLowEnergySecondaryPhotons,cutg);
236
237 G4double cute = (*(theCoupleTable->GetEnergyCutsVector(1)))[index];
238 cute = std::min(cutForLowEnergySecondaryPhotons,cute);
239
240 G4DynamicParticle* aPhoton;
241
242 // Generation of fluorescence
243 // Data in EADL are available only for Z > 5
244 // Protection to avoid generating photons in the unphysical case of
245 // shell binding energy > photon energy
246 if (Z > 5 && (bindingEnergy > cutg || bindingEnergy > cute))
247 {
248 photonVector = deexcitationManager.GenerateParticles(Z,shellId);
249 nTotPhotons = photonVector->size();
250 for (size_t k=0; k<nTotPhotons; k++)
251 {
252 aPhoton = (*photonVector)[k];
253 if (aPhoton)
254 {
255 G4double itsCut = cutg;
256 if(aPhoton->GetDefinition() == G4Electron::Electron()) itsCut = cute;
257 G4double itsEnergy = aPhoton->GetKineticEnergy();
258
259 if (itsEnergy > itsCut && itsEnergy <= bindingEnergy)
260 {
261 nPhotons++;
262 // Local energy deposit is given as the sum of the
263 // energies of incident photons minus the energies
264 // of the outcoming fluorescence photons
265 bindingEnergy -= itsEnergy;
266
267 }
268 else
269 {
270 delete aPhoton;
271 (*photonVector)[k] = 0;
272 }
273 }
274 }
275 }
276
277 energyDeposit += bindingEnergy;
278
279 G4int nSecondaries = nElectrons + nPhotons;
280 aParticleChange.SetNumberOfSecondaries(nSecondaries);
281
282 for (G4int l = 0; l<nElectrons; l++ )
283 {
284 aPhoton = electronVector[l];
285 if(aPhoton) {
286 aParticleChange.AddSecondary(aPhoton);
287 }
288 }
289 for ( size_t ll = 0; ll < nTotPhotons; ll++)
290 {
291 aPhoton = (*photonVector)[ll];
292 if(aPhoton) {
293 aParticleChange.AddSecondary(aPhoton);
294 }
295 }
296
297 delete photonVector;
298
299 if (energyDeposit < 0)
300 {
301 G4cout << "WARNING - "
302 << "G4LowEnergyPhotoElectric::PostStepDoIt - Negative energy deposit"
303 << G4endl;
304 energyDeposit = 0;
305 }
306
307 // Kill the incident photon
308 aParticleChange.ProposeMomentumDirection( 0., 0., 0. );
309 aParticleChange.ProposeEnergy( 0. );
310
311 aParticleChange.ProposeLocalEnergyDeposit(energyDeposit);
312 aParticleChange.ProposeTrackStatus( fStopAndKill );
313
314 // Reset NbOfInteractionLengthLeft and return aParticleChange
315 return G4VDiscreteProcess::PostStepDoIt( aTrack, aStep );
316 }
317
318 G4bool G4LowEnergyPhotoElectric::IsApplicable(const G4ParticleDefinition& particle)
319 {
320 return ( &particle == G4Gamma::Gamma() );
321 }
322
323 G4double G4LowEnergyPhotoElectric::GetMeanFreePath(const G4Track& track,
324 G4double, // previousStepSize
325 G4ForceCondition*)
326 {
327 const G4DynamicParticle* photon = track.GetDynamicParticle();
328 G4double energy = photon->GetKineticEnergy();
329 G4Material* material = track.GetMaterial();
330 // size_t materialIndex = material->GetIndex();
331
332 G4double meanFreePath = DBL_MAX;
333
334 // if (energy > highEnergyLimit)
335 // meanFreePath = meanFreePathTable->FindValue(highEnergyLimit,materialIndex);
336 // else if (energy < lowEnergyLimit) meanFreePath = DBL_MAX;
337 // else meanFreePath = meanFreePathTable->FindValue(energy,materialIndex);
338
339 G4double cross = shellCrossSectionHandler->ValueForMaterial(material,energy);
340 if(cross > 0.0) meanFreePath = 1.0/cross;
341
342 return meanFreePath;
343 }
344
345 void G4LowEnergyPhotoElectric::SetCutForLowEnSecPhotons(G4double cut)
346 {
347 cutForLowEnergySecondaryPhotons = cut;
348 deexcitationManager.SetCutForSecondaryPhotons(cut);
349 }
350
351 void G4LowEnergyPhotoElectric::SetCutForLowEnSecElectrons(G4double cut)
352 {
353 cutForLowEnergySecondaryElectrons = cut;
354 deexcitationManager.SetCutForAugerElectrons(cut);
355 }
356
357 void G4LowEnergyPhotoElectric::ActivateAuger(G4bool val)
358 {
359 deexcitationManager.ActivateAugerElectronProduction(val);
360 }
361
362 void G4LowEnergyPhotoElectric::SetAngularGenerator(G4RDVPhotoElectricAngularDistribution* distribution)
363 {
364 ElectronAngularGenerator = distribution;
365 ElectronAngularGenerator->PrintGeneratorInformation();
366 }
367
368 void G4LowEnergyPhotoElectric::SetAngularGenerator(const G4String& name)
369 {
370 if (name == "default")
371 {
372 delete ElectronAngularGenerator;
373 ElectronAngularGenerator = new G4RDPhotoElectricAngularGeneratorSimple("GEANT4LowEnergySimpleGenerator");
374 generatorName = name;
375 }
376 else if (name == "standard")
377 {
378 delete ElectronAngularGenerator;
379 ElectronAngularGenerator = new G4RDPhotoElectricAngularGeneratorSauterGavrila("GEANT4SauterGavrilaGenerator");
380 generatorName = name;
381 }
382 else if (name == "polarized")
383 {
384 delete ElectronAngularGenerator;
385 ElectronAngularGenerator = new G4RDPhotoElectricAngularGeneratorPolarized("GEANT4LowEnergyPolarizedGenerator");
386 generatorName = name;
387 }
388 else
389 {
390 G4Exception("G4LowEnergyPhotoElectric::SetAngularGenerator()",
391 "InvalidSetup", FatalException,
392 "Generator does not exist!");
393 }
394
395 ElectronAngularGenerator->PrintGeneratorInformation();
396 }
397