include/Geant4/G4AdjointPhotoElectricModel.hh

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0026 ////////////////////////////////////////////////////////////////////////////////
0027 //  Class:   G4AdjointPhotoElectricModel
0028 //  Author:         L. Desorgher
0029 //  Organisation:   SpaceIT GmbH
0030 //
0031 //  Model for the adjoint photo electric process.
0032 //  Put a higher limit on the CS to avoid a high rate of Inverse Photo e-effect
0033 //  at low energy. The very high adjoint CS of the reverse photo electric
0034 //  reaction produce a high rate of reverse photo electric reaction in the inner
0035 //  side of a shielding for eaxmple, the correction of this occurrence by weight
0036 //  correction in the StepDoIt method is not statistically sufficient at small
0037 //  energy. The problem is partially solved by setting a higher CS limit and
0038 //  compensating it by an extra weight correction factor. However when coupling
0039 //  it with other reverse processes the reverse photo-electric is still the
0040 //  source of very occasional high weights that decrease the efficiency of the
0041 //  computation. A way to solve this problemn is still needed but is difficult
0042 //  to find as it happens in rare cases but does give a weight that is outside
0043 //  the normal distribution. (Very Tricky!)
0044 //
0045 ////////////////////////////////////////////////////////////////////////////////
0046
0047 #ifndef G4AdjointPhotoElectricModel_h
0048 #define G4AdjointPhotoElectricModel_h 1
0049
0050 #include "globals.hh"
0051 #include "G4VEmAdjointModel.hh"
0052
0053 class G4AdjointPhotoElectricModel : public G4VEmAdjointModel
0054 {
0055  public:
0056   G4AdjointPhotoElectricModel();
0057   ~G4AdjointPhotoElectricModel() override;
0058
0059   void SampleSecondaries(const G4Track& aTrack, G4bool isScatProjToProj,
0060                          G4ParticleChange* fParticleChange) override;
0061
0062   G4double AdjointCrossSection(const G4MaterialCutsCouple* aCouple,
0063                                G4double primEnergy,
0064                                G4bool isScatProjToProj) override;
0065
0066   G4double AdjointCrossSectionPerAtom(const G4Element* anElement,
0067                                       G4double electronEnergy);
0068
0069   G4AdjointPhotoElectricModel(G4AdjointPhotoElectricModel&) = delete;
0070   G4AdjointPhotoElectricModel& operator=(
0071     const G4AdjointPhotoElectricModel& right) = delete;
0072
0073  protected:
0074   void CorrectPostStepWeight(G4ParticleChange* fParticleChange,
0075                              G4double old_weight, G4double adjointPrimKinEnergy,
0076                              G4double projectileKinEnergy,
0077                              G4bool isScatProjToProj) override;
0078
0079  private:
0080   void DefineCurrentMaterialAndElectronEnergy(
0081     const G4MaterialCutsCouple* aCouple, G4double eEnergy);
0082
0083   G4double fShellProb[40][40];
0084   G4double fXsec[40];
0085   G4double fTotAdjointCS      = 0.;
0086   G4double fFactorCSBiasing   = 1.;
0087   G4double fPreStepAdjointCS  = 0.;
0088   G4double fPostStepAdjointCS = 0.;
0089   G4double fCurrenteEnergy    = 0.;
0090
0091   size_t fIndexElement = 0;
0092 };
0093
0094 #endif