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// $Id: G4Generator2BS.hh,v 1.5 2010/10/14 14:00:29 vnivanch Exp $
// GEANT4 tag $Name: geant4-09-04-ref-00 $
//
// -------------------------------------------------------------------
//
// GEANT4 Class file
//
//
// File name:  G4Generator2BS
//
// Author:     Andreia Trindade (andreia@lip.pt)
//             Pedro Rodrigues  (psilva@lip.pt)
//             Luis Peralta     (luis@lip.pt)
// 
// Creation date: 2 June 2003
//
// Modifications: 
// 02 Jun 2003  First implementation acording with new design
// 12 Oct 2010  V.Ivanchenko moved RejectionFunction inline
//               
//
// Class Description: 
//
// Concrete class for Bremsstrahlung Angular Distribution Generation 
// 2BS Distribution
//

// -------------------------------------------------------------------
//

#ifndef G4Generator2BS_h
#define G4Generator2BS_h 1

#include "G4ios.hh"
#include "globals.hh"
#include "G4VBremAngularDistribution.hh"

class G4Pow;

class G4Generator2BS : public G4VBremAngularDistribution
{

public:

  G4Generator2BS(const G4String& name="");

  virtual ~G4Generator2BS();

  G4double PolarAngle(const G4double initial_energy,
		      const G4double final_energy,
		      const G4int Z);

  void PrintGeneratorInformation() const;

protected:

  inline G4double RejectionFunction(G4double value) const;

private:

  G4double z;
  G4double rejection_argument1, rejection_argument2, rejection_argument3;
  G4double EnergyRatio;

  G4Pow* g4pow;

  // hide assignment operator 
  G4Generator2BS & operator=(const  G4Generator2BS &right);
  G4Generator2BS(const  G4Generator2BS&);

};

inline G4double G4Generator2BS::RejectionFunction(G4double value) const
{
  G4double argument = (1+value)*(1+value);
  return (4+std::log(rejection_argument3+(z/argument)))*
    ((4*EnergyRatio*value/argument)-rejection_argument1)+rejection_argument2;
}

#endif

