G4GammaConversionToMuons.hh

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//
//         ------------ G4GammaConversionToMuons physics process ------
//         by H.Burkhardt, S. Kelner and R. Kokoulin, April 2002
// -----------------------------------------------------------------------------
//
// 05-08-04: suppression of .icc file (mma)
// 13-08-04, public ComputeCrossSectionPerAtom() and ComputeMeanFreePath() (mma)
//
// class description
//
// gamma ---> mu+ mu-
// inherit from G4VDiscreteProcess
//
 
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#ifndef G4GammaConversionToMuons_h
#define G4GammaConversionToMuons_h 1
 
#include "G4ios.hh"
#include "globals.hh"
#include "Randomize.hh"
#include "G4VDiscreteProcess.hh"
#include "G4PhysicsTable.hh"
#include "G4PhysicsLogVector.hh"
#include "G4ParticleDefinition.hh"
#include "G4Element.hh"
#include "G4Step.hh"
 
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class G4LossTableManager;
class G4BetheHeitler5DModel;
 
class G4GammaConversionToMuons : public G4VDiscreteProcess
{
public:  // with description
 
  explicit G4GammaConversionToMuons(
                        const G4String& processName ="GammaToMuPair",
                        G4ProcessType type = fElectromagnetic);
 
  ~G4GammaConversionToMuons() override;
 
  G4bool IsApplicable(const G4ParticleDefinition&) override;
       // true for Gamma only.
 
  void BuildPhysicsTable(const G4ParticleDefinition&) override;
       // here dummy, the total cross section parametrization is used rather
       // than tables,  just calling PrintInfoDefinition
 
  void PrintInfoDefinition();
       // Print few lines of informations about the process: validity range,
       // origine ..etc..
       // Invoked by BuildThePhysicsTable().
 
  void SetCrossSecFactor(G4double fac);
       // Set the factor to artificially increase the crossSection (default 1)
 
  inline G4double GetCrossSecFactor() const { return CrossSecFactor;}
       // Get the factor to artificially increase the cross section
 
  G4double GetMeanFreePath(const G4Track& aTrack,
                           G4double previousStepSize,
                           G4ForceCondition* condition) override;
       // It returns the MeanFreePath of the process for the current track :
       // (energy, material)
       // The previousStepSize and G4ForceCondition* are not used.
       // This function overloads a virtual function of the base class.
       // It is invoked by the ProcessManager of the Particle.
 
  G4double GetCrossSectionPerAtom(const G4DynamicParticle* aDynamicGamma,
                                  const G4Element* anElement);
       // It returns the total CrossSectionPerAtom of the process,
       // for the current DynamicGamma (energy), in anElement.
 
  G4VParticleChange* PostStepDoIt(const G4Track& aTrack,
                  const G4Step& aStep) override;
       // It computes the final state of the process (at end of step),
       // returned as a ParticleChange object.
       // This function overloads a virtual function of the base class.
       // It is invoked by the ProcessManager of the Particle.
 
  G4double ComputeCrossSectionPerAtom(G4double GammaEnergy, G4int Z);
 
  G4double ComputeMeanFreePath (G4double GammaEnergy,
                                const G4Material* aMaterial);
 
  // hide assignment operator as private
  G4GammaConversionToMuons& 
  operator=(const G4GammaConversionToMuons &right) = delete;
  G4GammaConversionToMuons(const G4GammaConversionToMuons& ) = delete;
 
private:
 
  const G4Element* SelectRandomAtom(const G4DynamicParticle* aDynamicGamma,
                                    const G4Material* aMaterial);
 
  G4double Mmuon;
  G4double Rc;
  G4double LimitEnergy;          // energy limit for accurate x-section
  G4double LowestEnergyLimit;    // low  energy limit of the model
  G4double HighestEnergyLimit;   // high energy limit of the model
  G4double Energy5DLimit = 0.0;  // high energy limit for 5D final state sampling
 
  G4double MeanFreePath = DBL_MAX;// actual MeanFreePath (current medium)
  G4double CrossSecFactor = 1.0;  // factor to artificially increase
                                  // the cross section
 
  G4LossTableManager* fManager;
  G4BetheHeitler5DModel* f5Dmodel = nullptr;
  const G4ParticleDefinition* theGamma;
  const G4ParticleDefinition* theMuonPlus;
  const G4ParticleDefinition* theMuonMinus;
};
 
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#endif