include/Geant4/G4XTRGammaRadModel.hh

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0026 ///////////////////////////////////////////////////////////////////////////
0027 //
0028 // Rough model describing a gamma function distributed radiator of X-ray
0029 // transition radiation. XTR is considered to flux after radiator!
0030 // Thicknesses of plates and gas gaps are distributed according to gamma
0031 // distribution. x are thicknesses of plates or gas gaps:
0032 //
0033 // p(x) = (alpha/<x>)^alpha * x^(alpha-1) * std::exp(-alpha*x/<x>) / G(alpha)
0034 //
0035 // G(alpha) is Euler's gamma function.
0036 // Plates have mean <x> = fPlateThick > 0 and power alpha = fAlphaPlate > 0 :
0037 // Gas gaps have mean <x> = fGasThick > 0 and power alpha = fAlphaGas > 0 :
0038 // We suppose that:
0039 // formation zone ~ mean thickness << absorption length
0040 // for each material and in the range 1-100 keV. This allows us to simplify
0041 // interference effects in radiator stack (GetStackFactor method).
0042 //
0043 // History:
0044 //
0045 // 03.10.05 V. Grichine, first version
0046 //
0047
0048 #ifndef G4XTRGammaRadModel_h
0049 #define G4XTRGammaRadModel_h 1
0050
0051 #include "G4LogicalVolume.hh"
0052 #include "G4Material.hh"
0053 #include "G4VXTRenergyLoss.hh"
0054
0055 class G4XTRGammaRadModel : public G4VXTRenergyLoss
0056 {
0057  public:
0058   explicit G4XTRGammaRadModel(G4LogicalVolume* anEnvelope, G4double, G4double,
0059                               G4Material*, G4Material*, G4double, G4double,
0060                               G4int,
0061                               const G4String& processName = "XTRgammaRadiator");
0062   ~G4XTRGammaRadModel();
0063
0064   void ProcessDescription(std::ostream&) const override;
0065   void DumpInfo() const override { ProcessDescription(G4cout); };
0066
0067   G4double GetStackFactor(G4double energy, G4double gamma,
0068                           G4double varAngle) override;
0069 };
0070
0071 #endif