Geant4 Cross Reference

Cross-Referencing   Geant4
Geant4/processes/electromagnetic/lowenergy/src/G4PenelopePhotoElectricModel.cc

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  1 //
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 25 //
 26 //
 27 // Author: Luciano Pandola
 28 //
 29 // History:
 30 // --------
 31 // 08 Jan 2010   L Pandola  First implementation
 32 // 01 Feb 2011   L Pandola  Suppress fake energy-violation warning when Auger
 33 //                          is active.
 34 //                          Make sure that fluorescence/Auger is generated
 35 //                          only if above threshold
 36 // 25 May 2011   L Pandola  Renamed (make v2008 as default Penelope)
 37 // 10 Jun 2011   L Pandola  Migrate atomic deexcitation interface
 38 // 07 Oct 2011   L Pandola  Bug fix (potential violation of energy conservation)
 39 // 27 Sep 2013   L Pandola  Migrate to MT paradigm, only master model manages
 40 //                          tables.
 41 // 02 Oct 2013   L Pandola  Rewrite sampling algorithm of SelectRandomShell()
 42 //                          to improve CPU performances
 43 //
 44 
 45 #include "G4PenelopePhotoElectricModel.hh"
 46 #include "G4PhysicalConstants.hh"
 47 #include "G4SystemOfUnits.hh"
 48 #include "G4ParticleDefinition.hh"
 49 #include "G4MaterialCutsCouple.hh"
 50 #include "G4DynamicParticle.hh"
 51 #include "G4PhysicsTable.hh"
 52 #include "G4PhysicsFreeVector.hh"
 53 #include "G4ElementTable.hh"
 54 #include "G4Element.hh"
 55 #include "G4AtomicTransitionManager.hh"
 56 #include "G4AtomicShell.hh"
 57 #include "G4Gamma.hh"
 58 #include "G4Electron.hh"
 59 #include "G4AutoLock.hh"
 60 #include "G4LossTableManager.hh"
 61 #include "G4Exp.hh"
 62 
 63 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
 64 
 65 const G4int G4PenelopePhotoElectricModel::fMaxZ;
 66 G4PhysicsTable* G4PenelopePhotoElectricModel::fLogAtomicShellXS[] = {nullptr};
 67 
 68 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
 69 
 70 G4PenelopePhotoElectricModel::G4PenelopePhotoElectricModel(const G4ParticleDefinition* part,
 71                  const G4String& nam)
 72   :G4VEmModel(nam),fParticleChange(nullptr),fParticle(nullptr),
 73    fAtomDeexcitation(nullptr),fIsInitialised(false),fLocalTable(false)
 74 {
 75   fIntrinsicLowEnergyLimit = 100.0*eV;
 76   fIntrinsicHighEnergyLimit = 100.0*GeV;
 77   //  SetLowEnergyLimit(fIntrinsicLowEnergyLimit);
 78   SetHighEnergyLimit(fIntrinsicHighEnergyLimit);
 79   //
 80 
 81   if (part)
 82     SetParticle(part);
 83 
 84   fVerboseLevel= 0;
 85   // Verbosity scale:
 86   // 0 = nothing
 87   // 1 = warning for energy non-conservation
 88   // 2 = details of energy budget
 89   // 3 = calculation of cross sections, file openings, sampling of atoms
 90   // 4 = entering in methods
 91 
 92   //Mark this model as "applicable" for atomic deexcitation
 93   SetDeexcitationFlag(true);
 94 
 95   fTransitionManager = G4AtomicTransitionManager::Instance();
 96 }
 97 
 98 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
 99 
100 G4PenelopePhotoElectricModel::~G4PenelopePhotoElectricModel()
101 {
102   if (IsMaster() || fLocalTable)
103     {
104       for(G4int i=0; i<=fMaxZ; ++i) 
105   {
106     if(fLogAtomicShellXS[i]) { 
107       fLogAtomicShellXS[i]->clearAndDestroy();
108       delete fLogAtomicShellXS[i];
109       fLogAtomicShellXS[i] = nullptr;
110     }
111   }
112     }
113 }
114 
115 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
116 
117 void G4PenelopePhotoElectricModel::Initialise(const G4ParticleDefinition* particle,
118                 const G4DataVector& cuts)
119 {
120   if (fVerboseLevel > 3)
121     G4cout << "Calling  G4PenelopePhotoElectricModel::Initialise()" << G4endl;
122 
123   fAtomDeexcitation = G4LossTableManager::Instance()->AtomDeexcitation();
124   //Issue warning if the AtomicDeexcitation has not been declared
125   if (!fAtomDeexcitation)
126     {
127       G4cout << G4endl;
128       G4cout << "WARNING from G4PenelopePhotoElectricModel " << G4endl;
129       G4cout << "Atomic de-excitation module is not instantiated, so there will not be ";
130       G4cout << "any fluorescence/Auger emission." << G4endl;
131       G4cout << "Please make sure this is intended" << G4endl;
132     }
133 
134   SetParticle(particle);
135 
136   //Only the master model creates/fills/destroys the tables
137   if (IsMaster() && particle == fParticle)
138     {
139       G4ProductionCutsTable* theCoupleTable =
140   G4ProductionCutsTable::GetProductionCutsTable();
141 
142       for (G4int i=0;i<(G4int)theCoupleTable->GetTableSize();++i)
143   {
144     const G4Material* material =
145       theCoupleTable->GetMaterialCutsCouple(i)->GetMaterial();
146     const G4ElementVector* theElementVector = material->GetElementVector();
147 
148     for (std::size_t j=0;j<material->GetNumberOfElements();++j)
149       {
150         G4int iZ = theElementVector->at(j)->GetZasInt();
151         //read data files only in the master
152         if (!fLogAtomicShellXS[iZ])
153     ReadDataFile(iZ);
154       }
155   }
156 
157       InitialiseElementSelectors(particle,cuts);
158 
159       if (fVerboseLevel > 0) {
160   G4cout << "Penelope Photo-Electric model v2008 is initialized " << G4endl
161          << "Energy range: "
162          << LowEnergyLimit() / MeV << " MeV - "
163          << HighEnergyLimit() / GeV << " GeV";
164       }
165     }
166 
167   if(fIsInitialised) return;
168   fParticleChange = GetParticleChangeForGamma();
169   fIsInitialised = true;
170 
171 }
172 
173 void G4PenelopePhotoElectricModel::InitialiseLocal(const G4ParticleDefinition* part,
174                  G4VEmModel *masterModel)
175 {
176   if (fVerboseLevel > 3)
177     G4cout << "Calling  G4PenelopePhotoElectricModel::InitialiseLocal()" << G4endl;
178   //
179   //Check that particle matches: one might have multiple master models (e.g.
180   //for e+ and e-).
181   //
182   if (part == fParticle)
183     {
184       SetElementSelectors(masterModel->GetElementSelectors());
185 
186       //Get the const table pointers from the master to the workers
187       const G4PenelopePhotoElectricModel* theModel =
188   static_cast<G4PenelopePhotoElectricModel*> (masterModel);
189       for(G4int i=0; i<=fMaxZ; ++i) 
190   fLogAtomicShellXS[i] = theModel->fLogAtomicShellXS[i];
191       //Same verbosity for all workers, as the master
192       fVerboseLevel = theModel->fVerboseLevel;
193     }
194 
195  return;
196 }
197 
198 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
199 namespace { G4Mutex  PenelopePhotoElectricModelMutex = G4MUTEX_INITIALIZER; }
200 G4double G4PenelopePhotoElectricModel::ComputeCrossSectionPerAtom(
201                   const G4ParticleDefinition*,
202                   G4double energy,
203                   G4double Z, G4double,
204                   G4double, G4double)
205 {
206   //
207   // Penelope model v2008
208   //
209   if (fVerboseLevel > 3)
210     G4cout << "Calling ComputeCrossSectionPerAtom() of G4PenelopePhotoElectricModel" << G4endl;
211 
212   G4int iZ = G4int(Z);
213 
214   if (!fLogAtomicShellXS[iZ])
215     {
216       //If we are here, it means that Initialize() was inkoved, but the MaterialTable was
217       //not filled up. This can happen in a UnitTest or via G4EmCalculator
218       if (fVerboseLevel > 0)
219   {
220     //Issue a G4Exception (warning) only in verbose mode
221     G4ExceptionDescription ed;
222     ed << "Unable to retrieve the shell cross section table for Z=" << iZ << G4endl;
223     ed << "This can happen only in Unit Tests or via G4EmCalculator" << G4endl;
224     G4Exception("G4PenelopePhotoElectricModel::ComputeCrossSectionPerAtom()",
225           "em2038",JustWarning,ed);
226   }
227       //protect file reading via autolock
228       G4AutoLock lock(&PenelopePhotoElectricModelMutex);
229       ReadDataFile(iZ);
230       lock.unlock();
231     }
232 
233   G4double cross = 0;
234   G4PhysicsTable* theTable =  fLogAtomicShellXS[iZ];
235   G4PhysicsFreeVector* totalXSLog = (G4PhysicsFreeVector*) (*theTable)[0];
236 
237    if (!totalXSLog)
238      {
239        G4Exception("G4PenelopePhotoElectricModel::ComputeCrossSectionPerAtom()",
240        "em2039",FatalException,
241        "Unable to retrieve the total cross section table");
242        return 0;
243      }
244    G4double logene = G4Log(energy);
245    G4double logXS = totalXSLog->Value(logene);
246    cross = G4Exp(logXS);
247 
248   if (fVerboseLevel > 2)
249     G4cout << "Photoelectric cross section at " << energy/MeV << " MeV for Z=" << Z <<
250       " = " << cross/barn << " barn" << G4endl;
251   return cross;
252 }
253 
254 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
255 
256 void G4PenelopePhotoElectricModel::SampleSecondaries(std::vector<G4DynamicParticle*>* fvect,
257                  const G4MaterialCutsCouple* couple,
258                  const G4DynamicParticle* aDynamicGamma,
259                  G4double,
260                  G4double)
261 {
262   //
263   // Photoelectric effect, Penelope model v2008
264   //
265   // The target atom and the target shell are sampled according to the Livermore
266   // database
267   //  D.E. Cullen et al., Report UCRL-50400 (1989)
268   // The angular distribution of the electron in the final state is sampled
269   // according to the Sauter distribution from
270   //  F. Sauter, Ann. Phys. 11 (1931) 454
271   // The energy of the final electron is given by the initial photon energy minus
272   // the binding energy. Fluorescence de-excitation is subsequently produced
273   // (to fill the vacancy) according to the general Geant4 G4DeexcitationManager:
274   //  J. Stepanek, Comp. Phys. Comm. 1206 pp 1-1-9 (1997)
275 
276   if (fVerboseLevel > 3)
277     G4cout << "Calling SamplingSecondaries() of G4PenelopePhotoElectricModel" << G4endl;
278 
279   G4double photonEnergy = aDynamicGamma->GetKineticEnergy();
280 
281   // always kill primary
282   fParticleChange->ProposeTrackStatus(fStopAndKill);
283   fParticleChange->SetProposedKineticEnergy(0.);
284 
285   if (photonEnergy <= fIntrinsicLowEnergyLimit)
286     {
287       fParticleChange->ProposeLocalEnergyDeposit(photonEnergy);
288       return ;
289     }
290 
291   G4ParticleMomentum photonDirection = aDynamicGamma->GetMomentumDirection();
292 
293   // Select randomly one element in the current material
294   if (fVerboseLevel > 2)
295     G4cout << "Going to select element in " << couple->GetMaterial()->GetName() << G4endl;
296 
297   // atom can be selected efficiently if element selectors are initialised
298   const G4Element* anElement =
299     SelectRandomAtom(couple,G4Gamma::GammaDefinition(),photonEnergy);
300   G4int Z = anElement->GetZasInt();
301   if (fVerboseLevel > 2)
302     G4cout << "Selected " << anElement->GetName() << G4endl;
303 
304   // Select the ionised shell in the current atom according to shell cross sections
305   //shellIndex = 0 --> K shell
306   //             1-3 --> L shells
307   //             4-8 --> M shells
308   //             9 --> outer shells cumulatively
309   //
310   std::size_t shellIndex = SelectRandomShell(Z,photonEnergy);
311 
312   if (fVerboseLevel > 2)
313     G4cout << "Selected shell " << shellIndex << " of element " << anElement->GetName() << G4endl;
314 
315   // Retrieve the corresponding identifier and binding energy of the selected shell
316   const G4AtomicTransitionManager* transitionManager = G4AtomicTransitionManager::Instance();
317 
318   //The number of shell cross section possibly reported in the Penelope database
319   //might be different from the number of shells in the G4AtomicTransitionManager
320   //(namely, Penelope may contain more shell, especially for very light elements).
321   //In order to avoid a warning message from the G4AtomicTransitionManager, I
322   //add this protection. Results are anyway changed, because when G4AtomicTransitionManager
323   //has a shellID>maxID, it sets the shellID to the last valid shell.
324   std::size_t numberOfShells = (std::size_t) transitionManager->NumberOfShells(Z);
325   if (shellIndex >= numberOfShells)
326     shellIndex = numberOfShells-1;
327 
328   const G4AtomicShell* shell = fTransitionManager->Shell(Z,shellIndex);
329   G4double bindingEnergy = shell->BindingEnergy();
330 
331   //Penelope considers only K, L and M shells. Cross sections of outer shells are
332   //not included in the Penelope database. If SelectRandomShell() returns
333   //shellIndex = 9, it means that an outer shell was ionized. In this case the
334   //Penelope recipe is to set bindingEnergy = 0 (the energy is entirely assigned
335   //to the electron) and to disregard fluorescence.
336   if (shellIndex == 9)
337     bindingEnergy = 0.*eV;
338 
339   G4double localEnergyDeposit = 0.0;
340   G4double cosTheta = 1.0;
341 
342   // Primary outcoming electron
343   G4double eKineticEnergy = photonEnergy - bindingEnergy;
344 
345   // There may be cases where the binding energy of the selected shell is > photon energy
346   // In such cases do not generate secondaries
347   if (eKineticEnergy > 0.)
348     {
349       // The electron is created
350       // Direction sampled from the Sauter distribution
351       cosTheta = SampleElectronDirection(eKineticEnergy);
352       G4double sinTheta = std::sqrt(1-cosTheta*cosTheta);
353       G4double phi = twopi * G4UniformRand() ;
354       G4double dirx = sinTheta * std::cos(phi);
355       G4double diry = sinTheta * std::sin(phi);
356       G4double dirz = cosTheta ;
357       G4ThreeVector electronDirection(dirx,diry,dirz); //electron direction
358       electronDirection.rotateUz(photonDirection);
359       G4DynamicParticle* electron = new G4DynamicParticle (G4Electron::Electron(),
360                  electronDirection,
361                  eKineticEnergy);
362       fvect->push_back(electron);
363     }
364   else
365     bindingEnergy = photonEnergy;
366 
367   G4double energyInFluorescence = 0; //testing purposes
368   G4double energyInAuger = 0; //testing purposes
369 
370   //Now, take care of fluorescence, if required. According to the Penelope
371   //recipe, I have to skip fluoresence completely if shellIndex == 9
372   //(= sampling of a shell outer than K,L,M)
373   if (fAtomDeexcitation && shellIndex<9)
374     {
375       G4int index = couple->GetIndex();
376       if (fAtomDeexcitation->CheckDeexcitationActiveRegion(index))
377   {
378     std::size_t nBefore = fvect->size();
379     fAtomDeexcitation->GenerateParticles(fvect,shell,Z,index);
380     std::size_t nAfter = fvect->size();
381 
382     if (nAfter > nBefore) //actual production of fluorescence
383       {
384         for (std::size_t j=nBefore;j<nAfter;++j) //loop on products
385     {
386       G4double itsEnergy = ((*fvect)[j])->GetKineticEnergy();
387       if (itsEnergy < bindingEnergy) // valid secondary, generate it
388         {
389           bindingEnergy -= itsEnergy;
390           if (((*fvect)[j])->GetParticleDefinition() == G4Gamma::Definition())
391       energyInFluorescence += itsEnergy;
392           else if (((*fvect)[j])->GetParticleDefinition() == G4Electron::Definition())
393       energyInAuger += itsEnergy;
394         }
395       else //invalid secondary: takes more than the available energy: delete it
396         {
397           delete (*fvect)[j];
398           (*fvect)[j] = nullptr;
399         }       
400     }
401       }
402   }
403     }
404 
405   //Residual energy is deposited locally
406   localEnergyDeposit += bindingEnergy;
407 
408   if (localEnergyDeposit < 0) //Should not be: issue a G4Exception (warning)
409     {
410       G4Exception("G4PenelopePhotoElectricModel::SampleSecondaries()",
411       "em2099",JustWarning,"WARNING: Negative local energy deposit");
412       localEnergyDeposit = 0;
413     }
414 
415   fParticleChange->ProposeLocalEnergyDeposit(localEnergyDeposit);
416 
417   if (fVerboseLevel > 1)
418     {
419       G4cout << "-----------------------------------------------------------" << G4endl;
420       G4cout << "Energy balance from G4PenelopePhotoElectric" << G4endl;
421       G4cout << "Selected shell: " << WriteTargetShell(shellIndex) << " of element " <<
422   anElement->GetName() << G4endl;
423       G4cout << "Incoming photon energy: " << photonEnergy/keV << " keV" << G4endl;
424       G4cout << "-----------------------------------------------------------" << G4endl;
425       if (eKineticEnergy)
426   G4cout << "Outgoing electron " << eKineticEnergy/keV << " keV" << G4endl;
427       if (energyInFluorescence)
428   G4cout << "Fluorescence x-rays: " << energyInFluorescence/keV << " keV" << G4endl;
429       if (energyInAuger)
430   G4cout << "Auger electrons: " << energyInAuger/keV << " keV" << G4endl;
431       G4cout << "Local energy deposit " << localEnergyDeposit/keV << " keV" << G4endl;
432       G4cout << "Total final state: " <<
433   (eKineticEnergy+energyInFluorescence+localEnergyDeposit+energyInAuger)/keV <<
434   " keV" << G4endl;
435       G4cout << "-----------------------------------------------------------" << G4endl;
436     }
437   if (fVerboseLevel > 0)
438     {
439       G4double energyDiff =
440   std::fabs(eKineticEnergy+energyInFluorescence+localEnergyDeposit+energyInAuger-photonEnergy);
441       if (energyDiff > 0.05*keV)
442   {
443     G4cout << "Warning from G4PenelopePhotoElectric: problem with energy conservation: " <<
444       (eKineticEnergy+energyInFluorescence+localEnergyDeposit+energyInAuger)/keV
445      << " keV (final) vs. " <<
446       photonEnergy/keV << " keV (initial)" << G4endl;
447     G4cout << "-----------------------------------------------------------" << G4endl;
448     G4cout << "Energy balance from G4PenelopePhotoElectric" << G4endl;
449     G4cout << "Selected shell: " << WriteTargetShell(shellIndex) << " of element " <<
450       anElement->GetName() << G4endl;
451     G4cout << "Incoming photon energy: " << photonEnergy/keV << " keV" << G4endl;
452     G4cout << "-----------------------------------------------------------" << G4endl;
453     if (eKineticEnergy)
454       G4cout << "Outgoing electron " << eKineticEnergy/keV << " keV" << G4endl;
455     if (energyInFluorescence)
456       G4cout << "Fluorescence x-rays: " << energyInFluorescence/keV << " keV" << G4endl;
457     if (energyInAuger)
458       G4cout << "Auger electrons: " << energyInAuger/keV << " keV" << G4endl;
459     G4cout << "Local energy deposit " << localEnergyDeposit/keV << " keV" << G4endl;
460     G4cout << "Total final state: " <<
461       (eKineticEnergy+energyInFluorescence+localEnergyDeposit+energyInAuger)/keV <<
462       " keV" << G4endl;
463     G4cout << "-----------------------------------------------------------" << G4endl;
464   }
465     }
466 }
467 
468 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
469 
470 G4double G4PenelopePhotoElectricModel::SampleElectronDirection(G4double energy)
471 {
472   G4double costheta = 1.0;
473   if (energy>1*GeV) return costheta;
474 
475   //1) initialize energy-dependent variables
476   // Variable naming according to Eq. (2.24) of Penelope Manual
477   // (pag. 44)
478   G4double gamma = 1.0 + energy/electron_mass_c2;
479   G4double gamma2 = gamma*gamma;
480   G4double beta = std::sqrt((gamma2-1.0)/gamma2);
481 
482   // ac corresponds to "A" of Eq. (2.31)
483   //
484   G4double ac = (1.0/beta) - 1.0;
485   G4double a1 = 0.5*beta*gamma*(gamma-1.0)*(gamma-2.0);
486   G4double a2 = ac + 2.0;
487   G4double gtmax = 2.0*(a1 + 1.0/ac);
488 
489   G4double tsam = 0;
490   G4double gtr = 0;
491 
492   //2) sampling. Eq. (2.31) of Penelope Manual
493   // tsam = 1-std::cos(theta)
494   // gtr = rejection function according to Eq. (2.28)
495   do{
496     G4double rand = G4UniformRand();
497     tsam = 2.0*ac * (2.0*rand + a2*std::sqrt(rand)) / (a2*a2 - 4.0*rand);
498     gtr = (2.0 - tsam) * (a1 + 1.0/(ac+tsam));
499   }while(G4UniformRand()*gtmax > gtr);
500   costheta = 1.0-tsam;
501 
502   return costheta;
503 }
504 
505 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
506 
507 void G4PenelopePhotoElectricModel::ReadDataFile(G4int Z)
508 {
509   if (!IsMaster())
510       //Should not be here!
511     G4Exception("G4PenelopePhotoElectricModel::ReadDataFile()",
512     "em0100",FatalException,"Worker thread in this method");
513 
514   if (fVerboseLevel > 2)
515     {
516       G4cout << "G4PenelopePhotoElectricModel::ReadDataFile()" << G4endl;
517       G4cout << "Going to read PhotoElectric data files for Z=" << Z << G4endl;
518     }
519 
520     const char* path = G4FindDataDir("G4LEDATA");
521     if(!path)
522     {
523       G4String excep = "G4PenelopePhotoElectricModel - G4LEDATA environment variable not set!";
524       G4Exception("G4PenelopePhotoElectricModel::ReadDataFile()",
525       "em0006",FatalException,excep);
526       return;
527     }
528 
529   /*
530     Read the cross section file
531   */
532   std::ostringstream ost;
533   if (Z>9)
534     ost << path << "/penelope/photoelectric/pdgph" << Z << ".p08";
535   else
536     ost << path << "/penelope/photoelectric/pdgph0" << Z << ".p08";
537   std::ifstream file(ost.str().c_str());
538   if (!file.is_open())
539     {
540       G4String excep = "G4PenelopePhotoElectricModel - data file " + G4String(ost.str()) + " not found!";
541       G4Exception("G4PenelopePhotoElectricModel::ReadDataFile()",
542       "em0003",FatalException,excep);
543     }
544   //I have to know in advance how many points are in the data list
545   //to initialize the G4PhysicsFreeVector()
546   std::size_t ndata=0;
547   G4String line;
548   while( getline(file, line) )
549     ndata++;
550   ndata -= 1;
551   //G4cout << "Found: " << ndata << " lines" << G4endl;
552 
553   file.clear();
554   file.close();
555   file.open(ost.str().c_str());
556 
557   G4int readZ =0;
558   std::size_t nShells= 0;
559   file >> readZ >> nShells;
560 
561   if (fVerboseLevel > 3)
562     G4cout << "Element Z=" << Z << " , nShells = " << nShells << G4endl;
563 
564   //check the right file is opened.
565   if (readZ != Z || nShells <= 0 || nShells > 50) //protect nShell against large values
566     {
567       G4ExceptionDescription ed;
568       ed << "Corrupted data file for Z=" << Z << G4endl;
569       G4Exception("G4PenelopePhotoElectricModel::ReadDataFile()",
570       "em0005",FatalException,ed);
571       return;
572     }
573   G4PhysicsTable* thePhysicsTable = new G4PhysicsTable();
574   
575   //the table has to contain nShell+1 G4PhysicsFreeVectors,
576   //(theTable)[0] --> total cross section
577   //(theTable)[ishell] --> cross section for shell (ishell-1)
578 
579   //reserve space for the vectors
580   //everything is log-log
581   for (std::size_t i=0;i<nShells+1;++i)
582     thePhysicsTable->push_back(new G4PhysicsFreeVector(ndata));
583 
584   std::size_t k =0;
585   for (k=0;k<ndata && !file.eof();++k)
586     {
587       G4double energy = 0;
588       G4double aValue = 0;
589       file >> energy ;
590       energy *= eV;
591       G4double logene = G4Log(energy);
592       //loop on the columns
593       for (std::size_t i=0;i<nShells+1;++i)
594   {
595     file >> aValue;
596     aValue *= barn;
597     G4PhysicsFreeVector* theVec = (G4PhysicsFreeVector*) ((*thePhysicsTable)[i]);
598     if (aValue < 1e-40*cm2) //protection against log(0)
599       aValue = 1e-40*cm2;
600     theVec->PutValue(k,logene,G4Log(aValue));
601   }
602     }
603 
604   if (fVerboseLevel > 2)
605     {
606       G4cout << "G4PenelopePhotoElectricModel: read " << k << " points for element Z = "
607        << Z << G4endl;
608     }
609 
610   fLogAtomicShellXS[Z] = thePhysicsTable;
611 
612   file.close();
613   return;
614 }
615 
616 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
617 
618 std::size_t G4PenelopePhotoElectricModel::GetNumberOfShellXS(G4int Z)
619 {
620   if (!IsMaster())
621     //Should not be here!
622     G4Exception("G4PenelopePhotoElectricModel::GetNumberOfShellXS()",
623     "em0100",FatalException,"Worker thread in this method");
624 
625   //read data files
626   if (!fLogAtomicShellXS[Z])
627     ReadDataFile(Z);
628   //now it should be ok
629   if (!fLogAtomicShellXS[Z])
630      {
631        G4ExceptionDescription ed;
632        ed << "Cannot find shell cross section data for Z=" << Z << G4endl;
633        G4Exception("G4PenelopePhotoElectricModel::GetNumberOfShellXS()",
634        "em2038",FatalException,ed);
635      }
636   //one vector is allocated for the _total_ cross section
637   std::size_t nEntries = fLogAtomicShellXS[Z]->entries();
638   return  (nEntries-1);
639 }
640 
641 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
642 
643 G4double G4PenelopePhotoElectricModel::GetShellCrossSection(G4int Z,std::size_t shellID,G4double energy)
644 {
645   //this forces also the loading of the data
646   std::size_t entries = GetNumberOfShellXS(Z);
647 
648   if (shellID >= entries)
649     {
650       G4cout << "Element Z=" << Z << " has data for " << entries << " shells only" << G4endl;
651       G4cout << "so shellID should be from 0 to " << entries-1 << G4endl;
652       return 0;
653     }
654 
655   G4PhysicsTable* theTable =  fLogAtomicShellXS[Z];
656   //[0] is the total XS, shellID is in the element [shellID+1]
657   G4PhysicsFreeVector* totalXSLog = (G4PhysicsFreeVector*) (*theTable)[shellID+1];
658 
659   if (!totalXSLog)
660      {
661        G4Exception("G4PenelopePhotoElectricModel::GetShellCrossSection()",
662        "em2039",FatalException,
663        "Unable to retrieve the total cross section table");
664        return 0;
665      }
666    G4double logene = G4Log(energy);
667    G4double logXS = totalXSLog->Value(logene);
668    G4double cross = G4Exp(logXS);
669    if (cross < 2e-40*cm2) cross = 0;
670    return cross;
671 }
672 
673 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
674 
675 G4String G4PenelopePhotoElectricModel::WriteTargetShell(std::size_t shellID)
676 {
677   G4String theShell = "outer shell";
678   if (shellID == 0)
679     theShell = "K";
680   else if (shellID == 1)
681     theShell = "L1";
682   else if (shellID == 2)
683     theShell = "L2";
684   else if (shellID == 3)
685     theShell = "L3";
686   else if (shellID == 4)
687     theShell = "M1";
688   else if (shellID == 5)
689     theShell = "M2";
690   else if (shellID == 6)
691     theShell = "M3";
692   else if (shellID == 7)
693     theShell = "M4";
694   else if (shellID == 8)
695     theShell = "M5";
696 
697   return theShell;
698 }
699 
700 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...
701 
702 void G4PenelopePhotoElectricModel::SetParticle(const G4ParticleDefinition* p)
703 {
704   if(!fParticle) {
705     fParticle = p;
706   }
707 }
708 
709 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo...
710 
711 std::size_t G4PenelopePhotoElectricModel::SelectRandomShell(G4int Z,G4double energy)
712 {
713   G4double logEnergy = G4Log(energy);
714 
715   //Check if data have been read (it should be!)
716   if (!fLogAtomicShellXS[Z])
717      {
718        G4ExceptionDescription ed;
719        ed << "Cannot find shell cross section data for Z=" << Z << G4endl;
720        G4Exception("G4PenelopePhotoElectricModel::SelectRandomShell()",
721        "em2038",FatalException,ed);
722      }
723 
724   G4PhysicsTable* theTable =  fLogAtomicShellXS[Z];
725 
726   G4double sum = 0;
727   G4PhysicsFreeVector* totalXSLog = (G4PhysicsFreeVector*) (*theTable)[0];
728   G4double logXS = totalXSLog->Value(logEnergy);
729   G4double totalXS = G4Exp(logXS);
730 
731   //Notice: totalXS is the total cross section and it does *not* correspond to
732   //the sum of partialXS's, since these include only K, L and M shells.
733   //
734   // Therefore, here one have to consider the possibility of ionisation of
735   // an outer shell. Conventionally, it is indicated with id=10 in Penelope
736   //
737   G4double random = G4UniformRand()*totalXS;
738 
739   for (std::size_t k=1;k<theTable->entries();++k)
740     {
741       //Add one shell
742       G4PhysicsFreeVector* partialXSLog = (G4PhysicsFreeVector*) (*theTable)[k];
743       G4double logXSLocal = partialXSLog->Value(logEnergy);
744       G4double partialXS = G4Exp(logXSLocal);
745       sum += partialXS;
746       if (random <= sum)
747   return k-1;
748     }
749   //none of the shells K, L, M: return outer shell
750   return 9;
751 }
752