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26 ////////////////////////////////////////////////////////////////////////////////
27 // Class: G4AdjointPhotoElectricModel
28 // Author: L. Desorgher
29 // Organisation: SpaceIT GmbH
30 //
31 // Model for the adjoint photo electric process.
32 // Put a higher limit on the CS to avoid a high rate of Inverse Photo e-effect
33 // at low energy. The very high adjoint CS of the reverse photo electric
34 // reaction produce a high rate of reverse photo electric reaction in the inner
35 // side of a shielding for eaxmple, the correction of this occurrence by weight
36 // correction in the StepDoIt method is not statistically sufficient at small
37 // energy. The problem is partially solved by setting a higher CS limit and
38 // compensating it by an extra weight correction factor. However when coupling
39 // it with other reverse processes the reverse photo-electric is still the
40 // source of very occasional high weights that decrease the efficiency of the
41 // computation. A way to solve this problemn is still needed but is difficult
42 // to find as it happens in rare cases but does give a weight that is outside
43 // the normal distribution. (Very Tricky!)
44 //
45 ////////////////////////////////////////////////////////////////////////////////
46
47 #ifndef G4AdjointPhotoElectricModel_h
48 #define G4AdjointPhotoElectricModel_h 1
49
50 #include "globals.hh"
51 #include "G4VEmAdjointModel.hh"
52
53 class G4AdjointPhotoElectricModel : public G4VEmAdjointModel
54 {
55 public:
56 G4AdjointPhotoElectricModel();
57 ~G4AdjointPhotoElectricModel() override;
58
59 void SampleSecondaries(const G4Track& aTrack, G4bool isScatProjToProj,
60 G4ParticleChange* fParticleChange) override;
61
62 G4double AdjointCrossSection(const G4MaterialCutsCouple* aCouple,
63 G4double primEnergy,
64 G4bool isScatProjToProj) override;
65
66 G4double AdjointCrossSectionPerAtom(const G4Element* anElement,
67 G4double electronEnergy);
68
69 G4AdjointPhotoElectricModel(G4AdjointPhotoElectricModel&) = delete;
70 G4AdjointPhotoElectricModel& operator=(
71 const G4AdjointPhotoElectricModel& right) = delete;
72
73 protected:
74 void CorrectPostStepWeight(G4ParticleChange* fParticleChange,
75 G4double old_weight, G4double adjointPrimKinEnergy,
76 G4double projectileKinEnergy,
77 G4bool isScatProjToProj) override;
78
79 private:
80 void DefineCurrentMaterialAndElectronEnergy(
81 const G4MaterialCutsCouple* aCouple, G4double eEnergy);
82
83 G4double fShellProb[40][40];
84 G4double fXsec[40];
85 G4double fTotAdjointCS = 0.;
86 G4double fFactorCSBiasing = 1.;
87 G4double fPreStepAdjointCS = 0.;
88 G4double fPostStepAdjointCS = 0.;
89 G4double fCurrenteEnergy = 0.;
90
91 size_t fIndexElement = 0;
92 };
93
94 #endif
95