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//
// -------------------------------------------------------------------
//
// GEANT4 Class header file
//
//
// File name:     G4eplusAnnihilation
//
// Author:        Vladimir Ivanchenko on base of Michel Maire code
//
// Creation date: 02.08.2004
//
// Modifications:
// 08-11-04 Migration to new interface of Store/Retrieve tables (V.Ivanchenko)
// 15-03-05 Update interface according to changings 
//           in G4VEmProcess (V.Ivanchenko)
// 08-04-05 Major optimisation of internal interfaces (V.Ivanchenko)
// 04-05-05 Make class to be default (V.Ivanchenko)
// 04-12-05 SetProposedKineticEnergy(0.) for annihilated positron (mma)
// 09-08-06 add SetModel(G4VEmModel*) (mma)
// 12-09-06, move SetModel(G4VEmModel*) in G4VEmProcess (mma)
//
//
// Class Description:
//
// This class manages the process of e+ annihilation into 2 gammas
//

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

#ifndef G4eplusAnnihilation_h
#define G4eplusAnnihilation_h 1

#include "G4VEmProcess.hh"

class G4ParticleDefinition;

class G4eplusAnnihilation : public G4VEmProcess
{

public:

  explicit G4eplusAnnihilation(const G4String& name = "annihil");

  ~G4eplusAnnihilation() override;

  G4bool IsApplicable(const G4ParticleDefinition& p) final;

  G4VParticleChange* AtRestDoIt(
                             const G4Track& track,
                             const G4Step& stepData) override;

  G4double AtRestGetPhysicalInteractionLength(
                             const G4Track& track,
                             G4ForceCondition* condition
                            ) override;

  // print documentation in html format
  void ProcessDescription(std::ostream&) const override;

  G4eplusAnnihilation & operator=(const G4eplusAnnihilation &right) = delete;
  G4eplusAnnihilation(const G4eplusAnnihilation&) = delete;

protected:

  void InitialiseProcess(const G4ParticleDefinition*) override;

  // Print out of the class parameters
  void StreamProcessInfo(std::ostream& outFile) const override;

private:
  
  G4bool isInitialised = false;
  const G4ParticleDefinition* theGamma;
  const G4ParticleDefinition* theElectron;
  G4int fEntanglementModelID;
};

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

#endif
