include/Geant4/G4AnnihiToMuPair.hh

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0025 //
0026 //
0027 //
0028 //         ------------ G4AnnihiToMuPair physics process ------
0029 //         by H.Burkhardt, S. Kelner and R. Kokoulin, November 2002
0030 // -----------------------------------------------------------------------------
0031
0032 // class description
0033 //
0034 // (high energy) e+ (atomic) e- ---> mu+ mu-
0035 // inherit from G4VDiscreteProcess
0036 //
0037 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......//
0038 //
0039 // 04.02.03 : cosmetic simplifications (mma)
0040 // 27.01.03 : first implementation (hbu)
0041 //
0042 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0043
0044 #ifndef G4AnnihiToMuPair_h
0045 #define G4AnnihiToMuPair_h 1
0046
0047 #include "G4VDiscreteProcess.hh"
0048 #include "globals.hh"
0049
0050 class G4LossTableManager;
0051 class G4ParticleDefinition;
0052 class G4Track;
0053 class G4Step;
0054
0055 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0056
0057 class G4AnnihiToMuPair : public G4VDiscreteProcess
0058 {
0059 public:  // with description
0060
0061   explicit G4AnnihiToMuPair(const G4String& processName ="AnnihiToMuPair",
0062                 G4ProcessType type = fElectromagnetic);
0063
0064   ~G4AnnihiToMuPair() override;
0065
0066   G4bool IsApplicable(const G4ParticleDefinition&) override;
0067   // true for positron only.
0068
0069   void BuildPhysicsTable(const G4ParticleDefinition&) override;
0070   // here dummy, just calling PrintInfoDefinition
0071   // the total cross section is calculated analytically
0072
0073   void PrintInfoDefinition();
0074   // Print few lines of informations about the process: validity range,
0075   // origine ..etc..
0076   // Invoked by BuildPhysicsTable().
0077
0078   void SetCrossSecFactor(G4double fac);
0079   // Set the factor to artificially increase the crossSection (default 1)
0080
0081   G4double GetCrossSecFactor() {return fCrossSecFactor;};
0082   // Get the factor to artificially increase the cross section
0083
0084   G4double CrossSectionPerVolume(G4double positronEnergy, const G4Material*);
0085
0086   G4double ComputeCrossSectionPerElectron(const G4double energy);
0087
0088   G4double ComputeCrossSectionPerAtom(const G4double energy, const G4double Z);
0089
0090   G4double GetMeanFreePath(const G4Track& aTrack,
0091                G4double previousStepSize,
0092                G4ForceCondition* ) override;
0093   // It returns the MeanFreePath of the process for the current track :
0094   // (energy, material)
0095   // The previousStepSize and G4ForceCondition* are not used.
0096   // This function overloads a virtual function of the base class.
0097   // It is invoked by the ProcessManager of the Particle.
0098
0099   G4VParticleChange* PostStepDoIt(const G4Track& aTrack,
0100                   const G4Step& aStep) override;
0101   // It computes the final state of the process (at end of step),
0102   // returned as a ParticleChange object.
0103   // This function overloads a virtual function of the base class.
0104   // It is invoked by the ProcessManager of the Particle.
0105
0106   // hide assignment operator as private
0107   G4AnnihiToMuPair& operator=(const G4AnnihiToMuPair &right) = delete;
0108   G4AnnihiToMuPair(const G4AnnihiToMuPair& ) = delete;
0109
0110 private:
0111
0112   G4LossTableManager* fManager;
0113   const G4ParticleDefinition* part1;
0114   const G4ParticleDefinition* part2;
0115   G4double fMass;
0116
0117   G4double fLowEnergyLimit;  // Energy threshold of e+
0118   G4double fHighEnergyLimit; // Limit of validity of the model
0119   G4double fCurrentSigma;    // the last value of cross section per volume
0120   G4double fCrossSecFactor;  // factor to increase the cross section
0121   G4String fInfo = "e+e->mu+mu-";
0122 };
0123
0124 //....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
0125
0126 #endif
0127