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// $Id: G4Scintillation.hh,v 1.17 2010/05/27 20:48:35 gum Exp $
// GEANT4 tag $Name: geant4-09-04-beta-cand-01 $
//
// 
////////////////////////////////////////////////////////////////////////
// Scintillation Light Class Definition 
////////////////////////////////////////////////////////////////////////
//
// File:        G4Scintillation.hh  
// Description:	Discrete Process - Generation of Scintillation Photons
// Version:     1.0
// Created:     1998-11-07
// Author:      Peter Gumplinger
// Updated:     2005-07-28 add G4ProcessType to constructor
//              2002-11-21 change to user G4Poisson for small MeanNumPotons
//              2002-11-07 allow for fast and slow scintillation
//              2002-11-05 make use of constant material properties
//              2002-05-16 changed to inherit from VRestDiscreteProcess
//              2002-05-09 changed IsApplicable method
//              1999-10-29 add method and class descriptors
//
// mail:        gum@triumf.ca
//
////////////////////////////////////////////////////////////////////////

#ifndef G4Scintillation_h
#define G4Scintillation_h 1

/////////////
// Includes
/////////////

#include "globals.hh"
#include "templates.hh"
#include "Randomize.hh"
#include "G4Poisson.hh"
#include "G4ThreeVector.hh"
#include "G4ParticleMomentum.hh"
#include "G4Step.hh"
#include "G4VRestDiscreteProcess.hh"
#include "G4OpticalPhoton.hh"
#include "G4DynamicParticle.hh"
#include "G4Material.hh" 
#include "G4PhysicsTable.hh"
#include "G4MaterialPropertiesTable.hh"
#include "G4PhysicsOrderedFreeVector.hh"

#include "G4EmSaturation.hh"

// Class Description:
// RestDiscrete Process - Generation of Scintillation Photons.
// Class inherits publicly from G4VRestDiscreteProcess.
// Class Description - End:

/////////////////////
// Class Definition
/////////////////////

class G4Scintillation : public G4VRestDiscreteProcess
{

private:

        //////////////
        // Operators
        //////////////

	// G4Scintillation& operator=(const G4Scintillation &right);

public: // Without description

	////////////////////////////////
	// Constructors and Destructor
	////////////////////////////////

	G4Scintillation(const G4String& processName = "Scintillation",
                                 G4ProcessType type = fElectromagnetic);

	// G4Scintillation(const G4Scintillation &right);

	~G4Scintillation();	

        ////////////
        // Methods
        ////////////

public: // With description

        // G4Scintillation Process has both PostStepDoIt (for energy 
        // deposition of particles in flight) and AtRestDoIt (for energy
        // given to the medium by particles at rest)

        G4bool IsApplicable(const G4ParticleDefinition& aParticleType);
        // Returns true -> 'is applicable', for any particle type except
        // for an 'opticalphoton' and for short-lived particles

	G4double GetMeanFreePath(const G4Track& aTrack,
				       G4double ,
                                       G4ForceCondition* );
        // Returns infinity; i. e. the process does not limit the step,
        // but sets the 'StronglyForced' condition for the DoIt to be 
        // invoked at every step.

        G4double GetMeanLifeTime(const G4Track& aTrack,
                                 G4ForceCondition* );
        // Returns infinity; i. e. the process does not limit the time,
        // but sets the 'StronglyForced' condition for the DoIt to be
        // invoked at every step.

	G4VParticleChange* PostStepDoIt(const G4Track& aTrack, 
			                const G4Step&  aStep);
        G4VParticleChange* AtRestDoIt (const G4Track& aTrack,
                                       const G4Step& aStep);

        // These are the methods implementing the scintillation process.

	void SetTrackSecondariesFirst(const G4bool state);
        // If set, the primary particle tracking is interrupted and any
        // produced scintillation photons are tracked next. When all 
        // have been tracked, the tracking of the primary resumes.

        void SetFiniteRiseTime(const G4bool state);
        // If set, the G4Scintillation process expects the user to have
        // set the constant material property FAST/SLOWSCINTILLATIONRISETIME.

        G4bool GetTrackSecondariesFirst() const;
        // Returns the boolean flag for tracking secondaries first.

        G4bool GetFiniteRiseTime() const;
        // Returns the boolean flag for a finite scintillation rise time.
	
        void SetScintillationYieldFactor(const G4double yieldfactor);
        // Called to set the scintillation photon yield factor, needed when
        // the yield is different for different types of particles. This
        // scales the yield obtained from the G4MaterialPropertiesTable.

        G4double GetScintillationYieldFactor() const;
        // Returns the photon yield factor.

        void SetScintillationExcitationRatio(const G4double excitationratio);
        // Called to set the scintillation exciation ratio, needed when
        // the scintillation level excitation is different for different
        // types of particles. This overwrites the YieldRatio obtained
        // from the G4MaterialPropertiesTable.

        G4double GetScintillationExcitationRatio() const;
        // Returns the scintillation level excitation ratio.

        G4PhysicsTable* GetFastIntegralTable() const;
        // Returns the address of the fast scintillation integral table.

        G4PhysicsTable* GetSlowIntegralTable() const;
        // Returns the address of the slow scintillation integral table.

        void AddSaturation(G4EmSaturation* sat) { emSaturation = sat; }
        // Adds Birks Saturation to the process.

        G4EmSaturation* GetSaturation() const { return emSaturation; }
        // Returns the Birks Saturation.

        void DumpPhysicsTable() const;
        // Prints the fast and slow scintillation integral tables.

protected:

        void BuildThePhysicsTable();
        // It builds either the fast or slow scintillation integral table; 
        // or both. 

        ///////////////////////
        // Class Data Members
        ///////////////////////


        G4PhysicsTable* theSlowIntegralTable;
        G4PhysicsTable* theFastIntegralTable;



	G4bool fTrackSecondariesFirst;
        G4bool fFiniteRiseTime;

        G4double YieldFactor;

        G4double ExcitationRatio;

private:

        G4double single_exp(G4double t, G4double tau2);
        G4double bi_exp(G4double t, G4double tau1, G4double tau2);

        // emission time distribution when there is a finite rise time
        G4double sample_time(G4double tau1, G4double tau2);

        G4EmSaturation* emSaturation;

};

////////////////////
// Inline methods
////////////////////

inline 
G4bool G4Scintillation::IsApplicable(const G4ParticleDefinition& aParticleType)
{
       if (aParticleType.GetParticleName() == "opticalphoton") return false;
       if (aParticleType.IsShortLived()) return false;

       return true;
}

inline 
void G4Scintillation::SetTrackSecondariesFirst(const G4bool state) 
{ 
	fTrackSecondariesFirst = state;
}

inline
void G4Scintillation::SetFiniteRiseTime(const G4bool state)
{
        fFiniteRiseTime = state;
}

inline
G4bool G4Scintillation::GetTrackSecondariesFirst() const
{
        return fTrackSecondariesFirst;
}

inline 
G4bool G4Scintillation::GetFiniteRiseTime() const
{
        return fFiniteRiseTime;
}

inline
void G4Scintillation::SetScintillationYieldFactor(const G4double yieldfactor)
{
        YieldFactor = yieldfactor;
}

inline
G4double G4Scintillation::GetScintillationYieldFactor() const
{
        return YieldFactor;
}

inline
void G4Scintillation::SetScintillationExcitationRatio(const G4double excitationratio)
{
        ExcitationRatio = excitationratio;
}

inline
G4double G4Scintillation::GetScintillationExcitationRatio() const
{
        return ExcitationRatio;
}

inline
G4PhysicsTable* G4Scintillation::GetSlowIntegralTable() const
{
        return theSlowIntegralTable;
}

inline
G4PhysicsTable* G4Scintillation::GetFastIntegralTable() const
{
        return theFastIntegralTable;
}

inline
void G4Scintillation::DumpPhysicsTable() const
{
        if (theFastIntegralTable) {
           G4int PhysicsTableSize = theFastIntegralTable->entries();
           G4PhysicsOrderedFreeVector *v;

           for (G4int i = 0 ; i < PhysicsTableSize ; i++ )
           {
        	v = (G4PhysicsOrderedFreeVector*)(*theFastIntegralTable)[i];
        	v->DumpValues();
           }
         }

        if (theSlowIntegralTable) {
           G4int PhysicsTableSize = theSlowIntegralTable->entries();
           G4PhysicsOrderedFreeVector *v;

           for (G4int i = 0 ; i < PhysicsTableSize ; i++ )
           {
                v = (G4PhysicsOrderedFreeVector*)(*theSlowIntegralTable)[i];
                v->DumpValues();
           }
         }
}

inline
G4double G4Scintillation::single_exp(G4double t, G4double tau2)
{
         return exp(-1.0*t/tau2)/tau2;
}

inline
G4double G4Scintillation::bi_exp(G4double t, G4double tau1, G4double tau2)
{
         return exp(-1.0*t/tau2)*(1-exp(-1.0*t/tau1))/tau2/tau2*(tau1+tau2);
}

#endif /* G4Scintillation_h */
