source: trunk/source/processes/electromagnetic/standard/src/G4PAIModel.cc @ 1197

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update CVS release candidate geant4.9.3.01
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25//
26// $Id: G4PAIModel.cc,v 1.51 2009/08/12 21:28:50 vnivanch Exp $
27// GEANT4 tag $Name: geant4-09-03-cand-01 $
28//
29// -------------------------------------------------------------------
30//
31// GEANT4 Class
32// File name:     G4PAIModel.cc
33//
34// Author: Vladimir.Grichine@cern.ch on base of Vladimir Ivanchenko code
35//
36// Creation date: 05.10.2003
37//
38// Modifications:
39//
40// 17.08.04 V.Grichine, bug fixed for Tkin<=0 in SampleSecondary
41// 16.08.04 V.Grichine, bug fixed in massRatio for DEDX, CrossSection, SampleSecondary
42// 08.04.05 Major optimisation of internal interfaces (V.Ivantchenko)
43// 26.07.09 Fixed logic to work with several materials (V.Ivantchenko)
44//
45
46#include "G4Region.hh"
47#include "G4PhysicsLogVector.hh"
48#include "G4PhysicsFreeVector.hh"
49#include "G4PhysicsTable.hh"
50#include "G4ProductionCutsTable.hh"
51#include "G4MaterialCutsCouple.hh"
52#include "G4MaterialTable.hh"
53#include "G4SandiaTable.hh"
54#include "G4OrderedTable.hh"
55
56#include "G4PAIModel.hh"
57#include "Randomize.hh"
58#include "G4Electron.hh"
59#include "G4Positron.hh"
60#include "G4Poisson.hh"
61#include "G4Step.hh"
62#include "G4Material.hh"
63#include "G4DynamicParticle.hh"
64#include "G4ParticleDefinition.hh"
65#include "G4ParticleChangeForLoss.hh"
66
67////////////////////////////////////////////////////////////////////////
68
69using namespace std;
70
71G4PAIModel::G4PAIModel(const G4ParticleDefinition* p, const G4String& nam)
72  : G4VEmModel(nam),G4VEmFluctuationModel(nam),
73  fVerbose(0),
74  fLowestGamma(1.005),
75  fHighestGamma(10000.),
76  fTotBin(200),
77  fMeanNumber(20),
78  fParticle(0),
79  fHighKinEnergy(100.*TeV),
80  fTwoln10(2.0*log(10.0)),
81  fBg2lim(0.0169),
82  fTaulim(8.4146e-3)
83{
84  if(p) SetParticle(p);
85 
86  fElectron = G4Electron::Electron();
87  fPositron = G4Positron::Positron();
88
89  fPAItransferTable  = 0;
90  fPAIdEdxTable      = 0;
91  fSandiaPhotoAbsCof = 0;
92  fdEdxVector        = 0;
93  fLambdaVector      = 0;
94  fdNdxCutVector     = 0;
95
96  isInitialised      = false;
97}
98
99////////////////////////////////////////////////////////////////////////////
100
101G4PAIModel::~G4PAIModel()
102{
103  //  G4cout << "PAI: start destruction" << G4endl;
104  if(fParticleEnergyVector) delete fParticleEnergyVector;
105  if(fdEdxVector)           delete fdEdxVector ;
106  if(fLambdaVector)         delete fLambdaVector;
107  if(fdNdxCutVector)        delete fdNdxCutVector;
108
109  if( fPAItransferTable )
110    {
111      fPAItransferTable->clearAndDestroy();
112      delete fPAItransferTable ;
113    }
114  if( fPAIdEdxTable )
115    {
116      fPAIdEdxTable->clearAndDestroy();
117      delete fPAIdEdxTable ;
118    }
119  if(fSandiaPhotoAbsCof)
120    {
121      for(G4int i=0;i<fSandiaIntervalNumber;i++)
122        {
123          delete[] fSandiaPhotoAbsCof[i];
124        }
125      delete[] fSandiaPhotoAbsCof;
126    }
127  //G4cout << "PAI: end destruction" << G4endl;
128}
129
130///////////////////////////////////////////////////////////////////////////////
131
132void G4PAIModel::SetParticle(const G4ParticleDefinition* p)
133{
134  if(fParticle == p) return;
135  fParticle = p;
136  fMass = fParticle->GetPDGMass();
137  fSpin = fParticle->GetPDGSpin();
138  G4double q = fParticle->GetPDGCharge()/eplus;
139  fChargeSquare = q*q;
140  fLowKinEnergy = 0.2*MeV*fMass/proton_mass_c2;
141  fRatio = electron_mass_c2/fMass;
142  fQc = fMass/fRatio;
143}
144
145////////////////////////////////////////////////////////////////////////////
146
147void G4PAIModel::Initialise(const G4ParticleDefinition* p,
148                            const G4DataVector&)
149{
150  if(isInitialised) return;
151  isInitialised = true;
152
153  SetParticle(p);
154  fLowestKineticEnergy  = fMass*(fLowestGamma  - 1.0);
155  fHighestKineticEnergy = fMass*(fHighestGamma - 1.0);
156
157  fParticleEnergyVector = new G4PhysicsLogVector(fLowestKineticEnergy,
158                                                 fHighestKineticEnergy,
159                                                 fTotBin);
160
161  fParticleChange = GetParticleChangeForLoss();
162
163  // Prepare initialization
164  const G4ProductionCutsTable* theCoupleTable =
165        G4ProductionCutsTable::GetProductionCutsTable();
166  const G4MaterialTable* theMaterialTable = G4Material::GetMaterialTable();
167  size_t numOfMat   = G4Material::GetNumberOfMaterials();
168  size_t numRegions = fPAIRegionVector.size();
169
170  for(size_t iReg = 0; iReg < numRegions; ++iReg) // region loop
171  {
172    const G4Region* curReg = fPAIRegionVector[iReg];
173    for(size_t jMat = 0; jMat < numOfMat; ++jMat) // region material loop
174    {
175      fMaterial  = (*theMaterialTable)[jMat];
176      fCutCouple = theCoupleTable->GetMaterialCutsCouple( fMaterial, 
177                                          curReg->GetProductionCuts() );
178      //G4cout << "Reg <" <<curReg->GetName() << ">  mat <"
179      //             << fMaterial->GetName() << ">  fCouple= "
180      //             << fCutCouple<<"  " << p->GetParticleName() <<G4endl;
181      if( fCutCouple ) {
182        fMaterialCutsCoupleVector.push_back(fCutCouple);
183
184        fPAItransferTable = new G4PhysicsTable(fTotBin+1);
185        fPAIdEdxTable = new G4PhysicsTable(fTotBin+1);
186
187        fDeltaCutInKinEnergy = 
188          (*theCoupleTable->GetEnergyCutsVector(1))[fCutCouple->GetIndex()];
189     
190        //ComputeSandiaPhotoAbsCof();
191        BuildPAIonisationTable();
192
193        fPAIxscBank.push_back(fPAItransferTable);
194        fPAIdEdxBank.push_back(fPAIdEdxTable);
195        fdEdxTable.push_back(fdEdxVector);
196
197        BuildLambdaVector();
198        fdNdxCutTable.push_back(fdNdxCutVector);
199        fLambdaTable.push_back(fLambdaVector);
200      }
201    }
202  }
203}
204
205//////////////////////////////////////////////////////////////////
206
207void G4PAIModel::InitialiseMe(const G4ParticleDefinition*) 
208{}
209
210//////////////////////////////////////////////////////////////////
211
212void G4PAIModel::ComputeSandiaPhotoAbsCof()
213{ 
214  G4int i, j, numberOfElements ;
215  static const G4MaterialTable* theMaterialTable = G4Material::GetMaterialTable();
216
217  G4SandiaTable thisMaterialSandiaTable(fMatIndex) ;
218  numberOfElements = (*theMaterialTable)[fMatIndex]->
219                                              GetNumberOfElements();
220  G4int* thisMaterialZ = new G4int[numberOfElements] ;
221
222  for(i=0;i<numberOfElements;i++) 
223  {
224    thisMaterialZ[i] = 
225    (G4int)(*theMaterialTable)[fMatIndex]->GetElement(i)->GetZ() ;
226  } 
227  fSandiaIntervalNumber = thisMaterialSandiaTable.SandiaIntervals
228                           (thisMaterialZ,numberOfElements) ;
229
230  fSandiaIntervalNumber = thisMaterialSandiaTable.SandiaMixing
231                           ( thisMaterialZ ,
232                             (*theMaterialTable)[fMatIndex]->GetFractionVector() ,
233                             numberOfElements,fSandiaIntervalNumber) ;
234   
235  fSandiaPhotoAbsCof = new G4double*[fSandiaIntervalNumber] ;
236
237  for(i=0;i<fSandiaIntervalNumber;i++)  fSandiaPhotoAbsCof[i] = new G4double[5] ;
238   
239  for( i = 0 ; i < fSandiaIntervalNumber ; i++ )
240  {
241    fSandiaPhotoAbsCof[i][0] = thisMaterialSandiaTable.GetPhotoAbsorpCof(i+1,0) ; 
242
243    for( j = 1; j < 5 ; j++ )
244    {
245      fSandiaPhotoAbsCof[i][j] = thisMaterialSandiaTable.
246                                      GetPhotoAbsorpCof(i+1,j)*
247                 (*theMaterialTable)[fMatIndex]->GetDensity() ;
248    }
249  }
250  // delete[] thisMaterialZ ;
251}
252
253////////////////////////////////////////////////////////////////////////////
254//
255// Build tables for the ionization energy loss
256//  the tables are built for MATERIALS
257//                           *********
258
259void G4PAIModel::BuildPAIonisationTable()
260{
261  G4double LowEdgeEnergy , ionloss ;
262  G4double tau, Tmax, Tmin, Tkin, deltaLow, gamma, bg2 ;
263
264  fdEdxVector = new G4PhysicsLogVector( fLowestKineticEnergy,
265                                        fHighestKineticEnergy,
266                                        fTotBin);
267  G4SandiaTable* sandia = fMaterial->GetSandiaTable();
268
269  Tmin = sandia->GetSandiaCofForMaterialPAI(0,0)*keV;
270  deltaLow = 100.*eV; // 0.5*eV ;
271
272  for (G4int i = 0 ; i <= fTotBin ; i++)  //The loop for the kinetic energy
273  {
274    LowEdgeEnergy = fParticleEnergyVector->GetLowEdgeEnergy(i) ;
275    tau = LowEdgeEnergy/fMass ;
276    gamma = tau +1. ;
277    // G4cout<<"gamma = "<<gamma<<endl ;
278    bg2 = tau*( tau + 2. );
279    Tmax = MaxSecondaryEnergy(fParticle, LowEdgeEnergy); 
280    //    Tmax = std::min(fDeltaCutInKinEnergy, Tmax);
281    Tkin = Tmax ;
282
283    if ( Tmax < Tmin + deltaLow )  // low energy safety
284      Tkin = Tmin + deltaLow ;
285
286    fPAIySection.Initialize(fMaterial, Tkin, bg2);
287
288    // G4cout<<"ionloss = "<<ionloss*cm/keV<<" keV/cm"<<endl ;
289    // G4cout<<"n1 = "<<protonPAI.GetIntegralPAIxSection(1)*cm<<" 1/cm"<<endl ;
290    // G4cout<<"protonPAI.GetSplineSize() = "<<
291    //    protonPAI.GetSplineSize()<<G4endl<<G4endl ;
292
293    G4int n = fPAIySection.GetSplineSize();
294    G4PhysicsFreeVector* transferVector = new G4PhysicsFreeVector(n) ;
295    G4PhysicsFreeVector* dEdxVector = new G4PhysicsFreeVector(n);
296
297    for( G4int k = 0 ; k < n; k++ )
298    {
299      transferVector->PutValue( k ,
300                                fPAIySection.GetSplineEnergy(k+1),
301                                fPAIySection.GetIntegralPAIySection(k+1) ) ;
302      dEdxVector->PutValue( k ,
303                                fPAIySection.GetSplineEnergy(k+1),
304                                fPAIySection.GetIntegralPAIdEdx(k+1) ) ;
305    }
306    ionloss = fPAIySection.GetMeanEnergyLoss() ;   //  total <dE/dx>
307
308    if ( ionloss < DBL_MIN)  ionloss = DBL_MIN;
309    fdEdxVector->PutValue(i,ionloss) ;
310
311    fPAItransferTable->insertAt(i,transferVector) ;
312    fPAIdEdxTable->insertAt(i,dEdxVector) ;
313
314  }                                        // end of Tkin loop
315}
316
317///////////////////////////////////////////////////////////////////////
318//
319// Build mean free path tables for the delta ray production process
320//     tables are built for MATERIALS
321//
322
323void G4PAIModel::BuildLambdaVector()
324{
325  fLambdaVector = new G4PhysicsLogVector( fLowestKineticEnergy,
326                                          fHighestKineticEnergy,
327                                          fTotBin                ) ;
328  fdNdxCutVector = new G4PhysicsLogVector( fLowestKineticEnergy,
329                                          fHighestKineticEnergy,
330                                          fTotBin                ) ;
331  if(fVerbose > 1)
332  {
333    G4cout<<"PAIModel DeltaCutInKineticEnergyNow = "
334          <<fDeltaCutInKinEnergy/keV<<" keV"<<G4endl;
335  }
336  for (G4int i = 0 ; i <= fTotBin ; i++ )
337  {
338    G4double dNdxCut = GetdNdxCut(i,fDeltaCutInKinEnergy) ;
339    //G4cout << "i= " << i << " x= " << dNdxCut << G4endl;
340    if(dNdxCut < 0.0) dNdxCut = 0.0; 
341    //    G4double lambda = dNdxCut <= DBL_MIN ? DBL_MAX: 1.0/dNdxCut ;
342    G4double lambda = DBL_MAX;
343    if(dNdxCut > 0.0) lambda = 1.0/dNdxCut;
344
345    fLambdaVector->PutValue(i, lambda) ;
346    fdNdxCutVector->PutValue(i, dNdxCut) ;
347  }
348}
349
350///////////////////////////////////////////////////////////////////////
351//
352// Returns integral PAI cross section for energy transfers >= transferCut
353
354G4double 
355G4PAIModel::GetdNdxCut( G4int iPlace, G4double transferCut)
356{ 
357  G4int iTransfer;
358  G4double x1, x2, y1, y2, dNdxCut;
359  // G4cout<<"iPlace = "<<iPlace<<"; "<<"transferCut = "<<transferCut<<G4endl;
360  // G4cout<<"size = "<<G4int((*fPAItransferTable)(iPlace)->GetVectorLength())
361  //           <<G4endl; 
362  for( iTransfer = 0 ; 
363       iTransfer < G4int((*fPAItransferTable)(iPlace)->GetVectorLength()) ; 
364       iTransfer++)
365  {
366    if(transferCut <= (*fPAItransferTable)(iPlace)->GetLowEdgeEnergy(iTransfer))
367    {
368      break ;
369    }
370  } 
371  if ( iTransfer >= G4int((*fPAItransferTable)(iPlace)->GetVectorLength()) )
372  {
373      iTransfer = (*fPAItransferTable)(iPlace)->GetVectorLength() - 1 ;
374  }
375  y1 = (*(*fPAItransferTable)(iPlace))(iTransfer-1) ;
376  y2 = (*(*fPAItransferTable)(iPlace))(iTransfer) ;
377  if(y1 < 0.0) y1 = 0.0;
378  if(y2 < 0.0) y2 = 0.0;
379  // G4cout<<"y1 = "<<y1<<"; "<<"y2 = "<<y2<<G4endl;
380  x1 = (*fPAItransferTable)(iPlace)->GetLowEdgeEnergy(iTransfer-1) ;
381  x2 = (*fPAItransferTable)(iPlace)->GetLowEdgeEnergy(iTransfer) ;
382  // G4cout<<"x1 = "<<x1<<"; "<<"x2 = "<<x2<<G4endl;
383
384  if ( y1 == y2 )    dNdxCut = y2 ;
385  else
386  {
387    //  if ( x1 == x2  ) dNdxCut = y1 + (y2 - y1)*G4UniformRand() ;
388    //    if ( std::abs(x1-x2) <= eV  ) dNdxCut = y1 + (y2 - y1)*G4UniformRand() ;
389    if ( std::abs(x1-x2) <= eV  ) dNdxCut = y1 + (y2 - y1)*0.5 ;
390    else             dNdxCut = y1 + (transferCut - x1)*(y2 - y1)/(x2 - x1) ;     
391  }
392  //  G4cout<<""<<dNdxCut<<G4endl;
393  if(dNdxCut < 0.0) dNdxCut = 0.0; 
394  return dNdxCut ;
395}
396///////////////////////////////////////////////////////////////////////
397//
398// Returns integral dEdx for energy transfers >= transferCut
399
400G4double 
401G4PAIModel::GetdEdxCut( G4int iPlace, G4double transferCut)
402{ 
403  G4int iTransfer;
404  G4double x1, x2, y1, y2, dEdxCut;
405  //G4cout<<"iPlace = "<<iPlace<<"; "<<"transferCut = "<<transferCut<<G4endl;
406  // G4cout<<"size = "<<G4int((*fPAIdEdxTable)(iPlace)->GetVectorLength())
407  //           <<G4endl; 
408  for( iTransfer = 0 ; 
409       iTransfer < G4int((*fPAIdEdxTable)(iPlace)->GetVectorLength()) ; 
410       iTransfer++)
411  {
412    if(transferCut <= (*fPAIdEdxTable)(iPlace)->GetLowEdgeEnergy(iTransfer))
413    {
414      break ;
415    }
416  } 
417  if ( iTransfer >= G4int((*fPAIdEdxTable)(iPlace)->GetVectorLength()) )
418  {
419      iTransfer = (*fPAIdEdxTable)(iPlace)->GetVectorLength() - 1 ;
420  }
421  y1 = (*(*fPAIdEdxTable)(iPlace))(iTransfer-1) ;
422  y2 = (*(*fPAIdEdxTable)(iPlace))(iTransfer) ;
423  if(y1 < 0.0) y1 = 0.0;
424  if(y2 < 0.0) y2 = 0.0;
425  //G4cout<<"y1 = "<<y1<<"; "<<"y2 = "<<y2<<G4endl;
426  x1 = (*fPAIdEdxTable)(iPlace)->GetLowEdgeEnergy(iTransfer-1) ;
427  x2 = (*fPAIdEdxTable)(iPlace)->GetLowEdgeEnergy(iTransfer) ;
428  //G4cout<<"x1 = "<<x1<<"; "<<"x2 = "<<x2<<G4endl;
429
430  if ( y1 == y2 )    dEdxCut = y2 ;
431  else
432  {
433    //  if ( x1 == x2  ) dEdxCut = y1 + (y2 - y1)*G4UniformRand() ;
434    //    if ( std::abs(x1-x2) <= eV  ) dEdxCut = y1 + (y2 - y1)*G4UniformRand() ;
435    if ( std::abs(x1-x2) <= eV  ) dEdxCut = y1 + (y2 - y1)*0.5 ;
436    else             dEdxCut = y1 + (transferCut - x1)*(y2 - y1)/(x2 - x1) ;     
437  }
438  //G4cout<<""<<dEdxCut<<G4endl;
439  if(dEdxCut < 0.0) dEdxCut = 0.0; 
440  return dEdxCut ;
441}
442
443//////////////////////////////////////////////////////////////////////////////
444
445G4double G4PAIModel::ComputeDEDXPerVolume(const G4Material*,
446                                          const G4ParticleDefinition* p,
447                                          G4double kineticEnergy,
448                                          G4double cutEnergy)
449{
450  G4int iTkin,iPlace;
451 
452  //G4double cut = std::min(MaxSecondaryEnergy(p, kineticEnergy), cutEnergy);
453  G4double cut = cutEnergy;
454
455  G4double massRatio  = fMass/p->GetPDGMass();
456  G4double scaledTkin = kineticEnergy*massRatio;
457  G4double charge     = p->GetPDGCharge();
458  G4double charge2    = charge*charge;
459  const G4MaterialCutsCouple* matCC = CurrentCouple();
460
461  size_t jMat = 0;
462  for(;jMat < fMaterialCutsCoupleVector.size(); ++jMat )
463  {
464    if( matCC == fMaterialCutsCoupleVector[jMat] ) break;
465  }
466  //G4cout << "jMat= " << jMat
467  //     << " jMax= " << fMaterialCutsCoupleVector.size()
468  //       << " matCC: " << matCC;
469  //if(matCC) G4cout << " mat: " << matCC->GetMaterial()->GetName();
470  //  G4cout << G4endl;
471  if(jMat == fMaterialCutsCoupleVector.size()) return 0.0;
472
473  fPAIdEdxTable = fPAIdEdxBank[jMat];
474  fdEdxVector = fdEdxTable[jMat];
475  for(iTkin = 0 ; iTkin <= fTotBin ; iTkin++)
476  {
477    if(scaledTkin < fParticleEnergyVector->GetLowEdgeEnergy(iTkin)) break ;   
478  }
479  //G4cout << "E= " << scaledTkin << " iTkin= " << iTkin
480  //     << "  " << fdEdxVector->GetVectorLength()<<G4endl;
481  iPlace = iTkin - 1;
482  if(iPlace < 0) iPlace = 0;
483  else if(iPlace >= fTotBin) iPlace = fTotBin-1;
484  G4double dEdx = charge2*( (*fdEdxVector)(iPlace) - GetdEdxCut(iPlace,cut) );
485  if( dEdx < 0.) dEdx = 0.;
486  return dEdx;
487}
488
489/////////////////////////////////////////////////////////////////////////
490
491G4double G4PAIModel::CrossSectionPerVolume( const G4Material*,
492                                            const G4ParticleDefinition* p,
493                                            G4double kineticEnergy,
494                                            G4double cutEnergy,
495                                            G4double maxEnergy  ) 
496{
497  G4int iTkin,iPlace;
498  G4double tmax = std::min(MaxSecondaryEnergy(p, kineticEnergy), maxEnergy);
499  if(tmax <= cutEnergy) return 0.0;
500  G4double massRatio  = fMass/p->GetPDGMass();
501  G4double scaledTkin = kineticEnergy*massRatio;
502  G4double charge     = p->GetPDGCharge();
503  G4double charge2    = charge*charge, cross, cross1, cross2;
504  const G4MaterialCutsCouple* matCC = CurrentCouple();
505
506  size_t jMat = 0;
507  for(;jMat < fMaterialCutsCoupleVector.size(); ++jMat )
508  {
509    if( matCC == fMaterialCutsCoupleVector[jMat] ) break;
510  }
511  if(jMat == fMaterialCutsCoupleVector.size()) return 0.0;
512
513  fPAItransferTable = fPAIxscBank[jMat];
514
515  for(iTkin = 0 ; iTkin <= fTotBin ; iTkin++)
516  {
517    if(scaledTkin < fParticleEnergyVector->GetLowEdgeEnergy(iTkin)) break ;   
518  }
519  iPlace = iTkin - 1;
520  if(iPlace < 0) iPlace = 0;
521  else if(iPlace >= fTotBin) iPlace = fTotBin-1; 
522
523  //G4cout<<"iPlace = "<<iPlace<<"; tmax = "
524  // <<tmax<<"; cutEnergy = "<<cutEnergy<<G4endl; 
525  cross1 = GetdNdxCut(iPlace,tmax) ;
526  //G4cout<<"cross1 = "<<cross1<<G4endl; 
527  cross2 = GetdNdxCut(iPlace,cutEnergy) ; 
528  //G4cout<<"cross2 = "<<cross2<<G4endl; 
529  cross  = (cross2-cross1)*charge2;
530  //G4cout<<"cross = "<<cross<<G4endl; 
531  if( cross < DBL_MIN) cross = 0.0;
532  //  if( cross2 < DBL_MIN) cross2 = DBL_MIN;
533
534  // return cross2;
535  return cross;
536}
537
538///////////////////////////////////////////////////////////////////////////
539//
540// It is analog of PostStepDoIt in terms of secondary electron.
541//
542 
543void G4PAIModel::SampleSecondaries(std::vector<G4DynamicParticle*>* vdp,
544                                   const G4MaterialCutsCouple* matCC,
545                                   const G4DynamicParticle* dp,
546                                   G4double tmin,
547                                   G4double maxEnergy)
548{
549  size_t jMat = 0;
550  for(;jMat < fMaterialCutsCoupleVector.size(); ++jMat )
551  {
552    if( matCC == fMaterialCutsCoupleVector[jMat] ) break;
553  }
554  if(jMat == fMaterialCutsCoupleVector.size()) return;
555
556  fPAItransferTable = fPAIxscBank[jMat];
557  fdNdxCutVector    = fdNdxCutTable[jMat];
558
559  G4double tmax = std::min(MaxSecondaryKinEnergy(dp), maxEnergy);
560  if( tmin >= tmax && fVerbose > 0)
561  {
562    G4cout<<"G4PAIModel::SampleSecondary: tmin >= tmax "<<G4endl;
563  }
564  G4ThreeVector direction= dp->GetMomentumDirection();
565  G4double particleMass  = dp->GetMass();
566  G4double kineticEnergy = dp->GetKineticEnergy();
567
568  G4double massRatio     = fMass/particleMass;
569  G4double scaledTkin    = kineticEnergy*massRatio;
570  G4double totalEnergy   = kineticEnergy + particleMass;
571  G4double pSquare       = kineticEnergy*(totalEnergy+particleMass);
572 
573  G4double deltaTkin     = GetPostStepTransfer(scaledTkin);
574
575  // G4cout<<"G4PAIModel::SampleSecondaries; deltaKIn = "<<deltaTkin/keV<<" keV "<<G4endl;
576
577  if( deltaTkin <= 0. && fVerbose > 0) 
578  {
579    G4cout<<"G4PAIModel::SampleSecondary e- deltaTkin = "<<deltaTkin<<G4endl;
580  }
581  if( deltaTkin <= 0.) return;
582
583  if( deltaTkin > tmax) deltaTkin = tmax;
584
585  G4double deltaTotalMomentum = sqrt(deltaTkin*(deltaTkin + 2. * electron_mass_c2 ));
586  G4double totalMomentum      = sqrt(pSquare);
587  G4double costheta           = deltaTkin*(totalEnergy + electron_mass_c2)
588                                /(deltaTotalMomentum * totalMomentum);
589
590  if( costheta > 0.99999 ) costheta = 0.99999;
591  G4double sintheta = 0.0;
592  G4double sin2 = 1. - costheta*costheta;
593  if( sin2 > 0.) sintheta = sqrt(sin2);
594
595  //  direction of the delta electron
596  G4double phi  = twopi*G4UniformRand(); 
597  G4double dirx = sintheta*cos(phi), diry = sintheta*sin(phi), dirz = costheta;
598
599  G4ThreeVector deltaDirection(dirx,diry,dirz);
600  deltaDirection.rotateUz(direction);
601  deltaDirection.unit();
602
603  // primary change
604  kineticEnergy -= deltaTkin;
605  G4ThreeVector dir = totalMomentum*direction - deltaTotalMomentum*deltaDirection;
606  direction = dir.unit();
607  fParticleChange->SetProposedKineticEnergy(kineticEnergy);
608  fParticleChange->SetProposedMomentumDirection(direction);
609
610  // create G4DynamicParticle object for e- delta ray
611  G4DynamicParticle* deltaRay = new G4DynamicParticle;
612  deltaRay->SetDefinition(G4Electron::Electron());
613  deltaRay->SetKineticEnergy( deltaTkin );  //  !!! trick for last steps /2.0 ???
614  deltaRay->SetMomentumDirection(deltaDirection); 
615
616  vdp->push_back(deltaRay);
617}
618
619
620///////////////////////////////////////////////////////////////////////
621//
622// Returns post step PAI energy transfer > cut electron energy according to passed
623// scaled kinetic energy of particle
624
625G4double 
626G4PAIModel::GetPostStepTransfer( G4double scaledTkin )
627{ 
628  // G4cout<<"G4PAIModel::GetPostStepTransfer"<<G4endl ;
629
630  G4int iTkin, iTransfer, iPlace  ;
631  G4double transfer = 0.0, position, dNdxCut1, dNdxCut2, E1, E2, W1, W2, W ;
632
633  for(iTkin=0;iTkin<=fTotBin;iTkin++)
634  {
635    if(scaledTkin < fParticleEnergyVector->GetLowEdgeEnergy(iTkin))  break ;
636  }
637  iPlace = iTkin - 1 ;
638  // G4cout<<"from search, iPlace = "<<iPlace<<G4endl ;
639  if(iPlace < 0) iPlace = 0;
640  else if(iPlace >= fTotBin) iPlace = fTotBin-1; 
641  dNdxCut1 = (*fdNdxCutVector)(iPlace) ; 
642  // G4cout<<"dNdxCut1 = "<<dNdxCut1<<G4endl ;
643
644
645  if(iTkin == fTotBin) // Fermi plato, try from left
646  {
647      position = dNdxCut1*G4UniformRand() ;
648
649      for( iTransfer = 0;
650 iTransfer < G4int((*fPAItransferTable)(iPlace)->GetVectorLength()); iTransfer++ )
651      {
652        if(position >= (*(*fPAItransferTable)(iPlace))(iTransfer)) break ;
653      }
654      transfer = GetEnergyTransfer(iPlace,position,iTransfer);
655  }
656  else
657  {
658    dNdxCut2 = (*fdNdxCutVector)(iPlace+1) ; 
659    // G4cout<<"dNdxCut2 = "<<dNdxCut2<<G4endl ;
660    if(iTkin == 0) // Tkin is too small, trying from right only
661    {
662      position = dNdxCut2*G4UniformRand() ;
663
664      for( iTransfer = 0;
665  iTransfer < G4int((*fPAItransferTable)(iPlace+1)->GetVectorLength()); iTransfer++ )
666      {
667        if(position >= (*(*fPAItransferTable)(iPlace+1))(iTransfer)) break ;
668      }
669      transfer = GetEnergyTransfer(iPlace+1,position,iTransfer);
670    } 
671    else // general case: Tkin between two vectors of the material
672    {
673      E1 = fParticleEnergyVector->GetLowEdgeEnergy(iTkin - 1) ; 
674      E2 = fParticleEnergyVector->GetLowEdgeEnergy(iTkin)     ;
675      W  = 1.0/(E2 - E1) ;
676      W1 = (E2 - scaledTkin)*W ;
677      W2 = (scaledTkin - E1)*W ;
678
679      position = ( dNdxCut1*W1 + dNdxCut2*W2 )*G4UniformRand() ;
680
681        // G4cout<<position<<"\t" ;
682
683      G4int iTrMax1, iTrMax2, iTrMax;
684
685      iTrMax1 = G4int((*fPAItransferTable)(iPlace)->GetVectorLength());
686      iTrMax2 = G4int((*fPAItransferTable)(iPlace+1)->GetVectorLength());
687
688      if (iTrMax1 >= iTrMax2) iTrMax = iTrMax2;
689      else                    iTrMax = iTrMax1;
690
691
692      for( iTransfer = 0; iTransfer < iTrMax; iTransfer++ )
693      {
694          if( position >=
695          ( (*(*fPAItransferTable)(iPlace))(iTransfer)*W1 +
696            (*(*fPAItransferTable)(iPlace+1))(iTransfer)*W2) ) break ;
697      }
698      transfer = GetEnergyTransfer(iPlace,position,iTransfer);
699    }
700  } 
701  // G4cout<<"PAImodel PostStepTransfer = "<<transfer/keV<<" keV"<<G4endl ;
702  if(transfer < 0.0 ) transfer = 0.0 ;
703  // if(transfer < DBL_MIN ) transfer = DBL_MIN;
704
705  return transfer ;
706}
707
708///////////////////////////////////////////////////////////////////////
709//
710// Returns random PAI energy transfer according to passed
711// indexes of particle kinetic
712
713G4double
714G4PAIModel::GetEnergyTransfer( G4int iPlace, G4double position, G4int iTransfer )
715{ 
716  G4int iTransferMax;
717  G4double x1, x2, y1, y2, energyTransfer;
718
719  if(iTransfer == 0)
720  {
721    energyTransfer = (*fPAItransferTable)(iPlace)->GetLowEdgeEnergy(iTransfer);
722  } 
723  else
724  {
725    iTransferMax = G4int((*fPAItransferTable)(iPlace)->GetVectorLength());
726
727    if ( iTransfer >= iTransferMax )  iTransfer = iTransferMax - 1;
728   
729    y1 = (*(*fPAItransferTable)(iPlace))(iTransfer-1);
730    y2 = (*(*fPAItransferTable)(iPlace))(iTransfer);
731
732    x1 = (*fPAItransferTable)(iPlace)->GetLowEdgeEnergy(iTransfer-1);
733    x2 = (*fPAItransferTable)(iPlace)->GetLowEdgeEnergy(iTransfer);
734
735    if ( x1 == x2 )    energyTransfer = x2;
736    else
737    {
738      if ( y1 == y2  ) energyTransfer = x1 + (x2 - x1)*G4UniformRand();
739      else
740      {
741        energyTransfer = x1 + (position - y1)*(x2 - x1)/(y2 - y1);
742      }
743    }
744  }
745  return energyTransfer;
746}
747
748///////////////////////////////////////////////////////////////////////
749
750G4double G4PAIModel::SampleFluctuations( const G4Material* material,
751                                         const G4DynamicParticle* aParticle,
752                                               G4double&,
753                                               G4double& step,
754                                               G4double&)
755{
756  size_t jMat = 0;
757  for(;jMat < fMaterialCutsCoupleVector.size(); ++jMat )
758  {
759    if( material == fMaterialCutsCoupleVector[jMat]->GetMaterial() ) break;
760  }
761  if(jMat == fMaterialCutsCoupleVector.size()) return 0.0;
762
763  fPAItransferTable = fPAIxscBank[jMat];
764  fdNdxCutVector   = fdNdxCutTable[jMat];
765
766  G4int iTkin, iTransfer, iPlace;
767  G4long numOfCollisions=0;
768
769  //G4cout<<"G4PAIModel::SampleFluctuations"<<G4endl ;
770  //G4cout<<"in: "<<fMaterialCutsCoupleVector[jMat]->GetMaterial()->GetName()<<G4endl;
771  G4double loss = 0.0, charge2 ;
772  G4double stepSum = 0., stepDelta, lambda, omega; 
773  G4double position, E1, E2, W1, W2, W, dNdxCut1, dNdxCut2, meanNumber;
774  G4bool numb = true;
775  G4double Tkin       = aParticle->GetKineticEnergy() ;
776  G4double MassRatio  = fMass/aParticle->GetDefinition()->GetPDGMass() ;
777  G4double charge     = aParticle->GetDefinition()->GetPDGCharge() ;
778  charge2             = charge*charge ;
779  G4double TkinScaled = Tkin*MassRatio ;
780
781  for(iTkin=0;iTkin<=fTotBin;iTkin++)
782  {
783    if(TkinScaled < fParticleEnergyVector->GetLowEdgeEnergy(iTkin))   break ;
784  }
785  iPlace = iTkin - 1 ; 
786  if(iPlace < 0) iPlace = 0;
787  else if(iPlace >= fTotBin) iPlace = fTotBin - 1;
788  //G4cout<<"from search, iPlace = "<<iPlace<<G4endl ;
789  dNdxCut1 = (*fdNdxCutVector)(iPlace) ; 
790  //G4cout<<"dNdxCut1 = "<<dNdxCut1<<G4endl ;
791
792  if(iTkin == fTotBin) // Fermi plato, try from left
793  {
794    meanNumber =((*(*fPAItransferTable)(iPlace))(0)-dNdxCut1)*step*charge2;
795    if(meanNumber < 0.) meanNumber = 0. ;
796    //  numOfCollisions = RandPoisson::shoot(meanNumber) ;
797    // numOfCollisions = G4Poisson(meanNumber) ;
798    if( meanNumber > 0.) lambda = step/meanNumber;
799    else                 lambda = DBL_MAX;
800    while(numb)
801    {
802     stepDelta = CLHEP::RandExponential::shoot(lambda);
803     stepSum += stepDelta;
804     if(stepSum >= step) break;
805     numOfCollisions++;
806    }   
807    //G4cout<<"##1 numOfCollisions = "<<numOfCollisions<<G4endl ;
808
809    while(numOfCollisions)
810    {
811      position = dNdxCut1+
812                 ((*(*fPAItransferTable)(iPlace))(0)-dNdxCut1)*G4UniformRand() ;
813
814      for( iTransfer = 0;
815   iTransfer < G4int((*fPAItransferTable)(iPlace)->GetVectorLength()); iTransfer++ )
816      {
817        if(position >= (*(*fPAItransferTable)(iPlace))(iTransfer)) break ;
818      }
819      omega = GetEnergyTransfer(iPlace,position,iTransfer);
820      //G4cout<<"G4PAIModel::SampleFluctuations, omega = "<<omega/keV<<" keV; "<<"\t";
821      loss += omega;
822      numOfCollisions-- ;
823    }
824  }
825  else
826  {
827    dNdxCut2 = (*fdNdxCutVector)(iPlace+1) ; 
828    //G4cout<<"dNdxCut2 = "<<dNdxCut2<< " iTkin= "<<iTkin<<" iPlace= "<<iPlace<<G4endl;
829 
830    if(iTkin == 0) // Tkin is too small, trying from right only
831    {
832      meanNumber =((*(*fPAItransferTable)(iPlace+1))(0)-dNdxCut2)*step*charge2;
833      if( meanNumber < 0. ) meanNumber = 0. ;
834      //  numOfCollisions = CLHEP::RandPoisson::shoot(meanNumber) ;
835      //  numOfCollisions = G4Poisson(meanNumber) ;
836      if( meanNumber > 0.) lambda = step/meanNumber;
837      else                 lambda = DBL_MAX;
838      while(numb)
839        {
840          stepDelta = CLHEP::RandExponential::shoot(lambda);
841          stepSum += stepDelta;
842          if(stepSum >= step) break;
843          numOfCollisions++;
844        }   
845
846      //G4cout<<"##2 numOfCollisions = "<<numOfCollisions<<G4endl ;
847
848      while(numOfCollisions)
849      {
850        position = dNdxCut2+
851                   ((*(*fPAItransferTable)(iPlace+1))(0)-dNdxCut2)*G4UniformRand();
852   
853        for( iTransfer = 0;
854   iTransfer < G4int((*fPAItransferTable)(iPlace+1)->GetVectorLength()); iTransfer++ )
855        {
856          if(position >= (*(*fPAItransferTable)(iPlace+1))(iTransfer)) break ;
857        }
858        omega = GetEnergyTransfer(iPlace,position,iTransfer);
859        //G4cout<<omega/keV<<"\t";
860        loss += omega;
861        numOfCollisions-- ;
862      }
863    } 
864    else // general case: Tkin between two vectors of the material
865    {
866      E1 = fParticleEnergyVector->GetLowEdgeEnergy(iTkin - 1) ; 
867      E2 = fParticleEnergyVector->GetLowEdgeEnergy(iTkin)     ;
868       W = 1.0/(E2 - E1) ;
869      W1 = (E2 - TkinScaled)*W ;
870      W2 = (TkinScaled - E1)*W ;
871
872      //G4cout << fPAItransferTable->size() << G4endl;
873      //G4cout<<"(*(*fPAItransferTable)(iPlace))(0) = "<<
874      //   (*(*fPAItransferTable)(iPlace))(0)<<G4endl ;
875      //G4cout<<"(*(*fPAItransferTable)(iPlace+1))(0) = "<<
876      //     (*(*fPAItransferTable)(iPlace+1))(0)<<G4endl ;
877
878      meanNumber=( ((*(*fPAItransferTable)(iPlace))(0)-dNdxCut1)*W1 + 
879                   ((*(*fPAItransferTable)(iPlace+1))(0)-dNdxCut2)*W2 )*step*charge2;
880      if(meanNumber<0.0) meanNumber = 0.0;
881      //  numOfCollisions = RandPoisson::shoot(meanNumber) ;
882      // numOfCollisions = G4Poisson(meanNumber) ;
883      if( meanNumber > 0.) lambda = step/meanNumber;
884      else                 lambda = DBL_MAX;
885      while(numb)
886        {
887          stepDelta = CLHEP::RandExponential::shoot(lambda);
888          stepSum += stepDelta;
889          if(stepSum >= step) break;
890          numOfCollisions++;
891        }   
892
893      //G4cout<<"##3 numOfCollisions = "<<numOfCollisions<<endl ;
894
895      while(numOfCollisions)
896      {
897        position = dNdxCut1*W1 + dNdxCut2*W2 +
898                 ( ( (*(*fPAItransferTable)(iPlace))(0)-dNdxCut1 )*W1 + 
899                    dNdxCut2+
900                  ( (*(*fPAItransferTable)(iPlace+1))(0)-dNdxCut2 )*W2 )*G4UniformRand();
901
902        // G4cout<<position<<"\t" ;
903
904        for( iTransfer = 0;
905    iTransfer < G4int((*fPAItransferTable)(iPlace)->GetVectorLength()); iTransfer++ )
906        {
907          if( position >=
908          ( (*(*fPAItransferTable)(iPlace))(iTransfer)*W1 + 
909            (*(*fPAItransferTable)(iPlace+1))(iTransfer)*W2) )
910          {
911              break ;
912          }
913        }
914        omega =  GetEnergyTransfer(iPlace,position,iTransfer);
915        //  G4cout<<omega/keV<<"\t";
916        loss += omega;
917        numOfCollisions-- ;   
918      }
919    }
920  } 
921  //G4cout<<"PAIModel AlongStepLoss = "<<loss/keV<<" keV, on step = "
922  //  <<step/mm<<" mm"<<G4endl ;
923  if(loss > Tkin) loss=Tkin;
924  if(loss < 0.  ) loss = 0.;
925  return loss ;
926
927}
928
929//////////////////////////////////////////////////////////////////////
930//
931// Returns the statistical estimation of the energy loss distribution variance
932//
933
934
935G4double G4PAIModel::Dispersion( const G4Material* material, 
936                                 const G4DynamicParticle* aParticle,
937                                       G4double& tmax, 
938                                       G4double& step       )
939{
940  G4double loss, sumLoss=0., sumLoss2=0., sigma2, meanLoss=0.;
941  for(G4int i = 0 ; i < fMeanNumber; i++)
942  {
943    loss      = SampleFluctuations(material,aParticle,tmax,step,meanLoss);
944    sumLoss  += loss;
945    sumLoss2 += loss*loss;
946  }
947  meanLoss = sumLoss/fMeanNumber;
948  sigma2   = meanLoss*meanLoss + (sumLoss2-2*sumLoss*meanLoss)/fMeanNumber;
949  return sigma2;
950}
951
952/////////////////////////////////////////////////////////////////////
953
954G4double G4PAIModel::MaxSecondaryEnergy( const G4ParticleDefinition* p,
955                                         G4double kinEnergy) 
956{
957  G4double tmax = kinEnergy;
958  if(p == fElectron) tmax *= 0.5;
959  else if(p != fPositron) { 
960    G4double mass = p->GetPDGMass();
961    G4double ratio= electron_mass_c2/mass;
962    G4double gamma= kinEnergy/mass + 1.0;
963    tmax = 2.0*electron_mass_c2*(gamma*gamma - 1.) /
964                  (1. + 2.0*gamma*ratio + ratio*ratio);
965  }
966  return tmax;
967}
968
969///////////////////////////////////////////////////////////////
970
971void G4PAIModel::DefineForRegion(const G4Region* r) 
972{
973  fPAIRegionVector.push_back(r);
974}
975
976//
977//
978/////////////////////////////////////////////////
979
980
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984
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