include/Geant4/G4Generator2BS.hh

0001 //
0002 // ********************************************************************
0003 // * License and Disclaimer                                           *
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0024 // ********************************************************************
0025 //
0026 //
0027 // -------------------------------------------------------------------
0028 //
0029 // GEANT4 Class file
0030 //
0031 //
0032 // File name:  G4Generator2BS
0033 //
0034 // Author:     Andreia Trindade (andreia@lip.pt)
0035 //             Pedro Rodrigues  (psilva@lip.pt)
0036 //             Luis Peralta     (luis@lip.pt)
0037 //
0038 // Creation date: 2 June 2003
0039 //
0040 // Modifications:
0041 // 02 Jun 2003  First implementation acording with new design
0042 // 12 Oct 2010  V.Ivanchenko moved RejectionFunction inline
0043 //
0044 //
0045 // Class Description:
0046 //
0047 // Concrete class for Bremsstrahlung Angular Distribution Generation
0048 // 2BS Distribution
0049 //
0050
0051 // -------------------------------------------------------------------
0052 //
0053
0054 #ifndef G4Generator2BS_h
0055 #define G4Generator2BS_h 1
0056
0057 #include "G4ios.hh"
0058 #include "globals.hh"
0059 #include "G4VEmAngularDistribution.hh"
0060 #include "G4Log.hh"
0061
0062 class G4Pow;
0063
0064 class G4Generator2BS : public G4VEmAngularDistribution
0065 {
0066
0067 public:
0068
0069   explicit G4Generator2BS(const G4String& name="");
0070
0071   virtual ~G4Generator2BS();
0072
0073   G4ThreeVector& SampleDirection(const G4DynamicParticle* dp,
0074                  G4double out_energy,
0075                  G4int Z,
0076                  const G4Material* mat = nullptr) override;
0077
0078   void PrintGeneratorInformation() const override;
0079
0080   G4Generator2BS & operator=(const  G4Generator2BS &right)= delete;
0081   G4Generator2BS(const  G4Generator2BS&) = delete;
0082
0083 protected:
0084   inline G4double RejectionFunction(G4double value) const;
0085
0086 private:
0087   G4Pow* g4pow;
0088
0089   G4double fz;
0090   G4double ratio;
0091   G4double ratio1;
0092   G4double ratio2;
0093   G4double delta;
0094
0095   G4int  nwarn;
0096
0097 };
0098
0099 inline G4double G4Generator2BS::RejectionFunction(G4double y) const
0100 {
0101   G4double y2 = (1 + y)*(1 + y);
0102   G4double x  = 4*y*ratio/y2;
0103   return 4*x - ratio1 - (ratio2 - x)*G4Log(delta + fz/y2);
0104 }
0105
0106 #endif
0107