//  Geant4 simulation for MuSR
//  AUTHOR: Toni SHIROKA, Paul Scherrer Institut, PSI
//  DATE  : 2008-05
//

//$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
//  Muonium Formation according to yield.cc function (through GetYields method).
//  Id    : lem4MuFormation.hh, v 1.4
//  Author: Taofiq PARAISO, T. Shiroka
//  Date  : 2007-12
//$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
                              
#ifndef   lem4MuFormation_h
#define   lem4MuFormation_h 1

#include "G4VDiscreteProcess.hh"
#include "G4ParticleTable.hh"

#include "yields.h"

/*! lem4MuFormation class defines the muonium formation process in the Carbon foil 
 *  according to yields from Gonin's paper Sci. Rev. Instrum. 65(3), 648-652 (1994).
 * \image html yields3.gif The muonium formation yields.
 * The main parameters are the foil thickness and muon energy. For a given energy, 
 * a corresponding proportion of the muons will be converted into Muonium.
 * Concretely, the muon is eliminated and replaced by a Muonium with identical 
 * properties, including time, energy, momentum, position etc.
 *
 * The process is executed at the END of a step, i.e. the muon is converted into 
 * Muonium AFTER flying through the Carbon foil (see also yields.h). */

class lem4MuFormation : public G4VDiscreteProcess
{
 public:
   
   lem4MuFormation(const G4String& name = "MuFormation", // process description
		   G4ProcessType aType = fElectromagnetic);

  ~lem4MuFormation();
  
  //! - Main method. Muonium formation process is executed at the END of a step. */
  G4VParticleChange* PostStepDoIt(
			     const G4Track&,
			     const G4Step&);
  
  G4double GetMeanFreePath(const G4Track& aTrack,
			   G4double previousStepSize,
			   G4ForceCondition* condition);


  //! Condition for process application (step Object).
  G4bool CheckCondition(const G4Step& aStep);
  
  //! Condition for process application (step Pointer).
  G4bool CheckCondition(const G4Step* aStep);
  
  
  G4String  p_name;
  G4bool condition;
  
  
  void GetDatas( const G4Step* aStep);
  // model parameters
  G4ParticleTable* particleTable; 
  G4ParticleDefinition* particle;
  Yields   Gonin;
  G4double yvector[3];
  G4double rnd;
  G4DynamicParticle *DP;
  
  //! The particle change object.
  G4VParticleChange fParticleChange; 
 
  void  PrepareSecondary(const G4Track&);
  G4Track* aSecondary;

  void InitializeSecondaries(const G4Track&);
};

#endif