[u/mrichter/AliRoot.git] / MUON / AliMUONTrackExtrap.h

#ifndef ALIMUONTRACKEXTRAP_H
#define ALIMUONTRACKEXTRAP_H
/* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 * See cxx source for full Copyright notice                               */

/*$Id$*/
// Revision of includes 07/05/2004

/// \ingroup rec
/// \class AliMUONTrackExtrap
/// \brief Track parameters in ALICE dimuon spectrometer
///
//////////////////////////////////////////////////////////////
/// Tools for track extrapolation in ALICE dimuon spectrometer
//////////////////////////////////////////////////////////////

#include <TObject.h>
#include <TMatrixD.h>

class AliMagF;
class AliMUONTrackParam;

class AliMUONTrackExtrap : public TObject 
{
 public:
	/// Constructor
  AliMUONTrackExtrap() : TObject(){};
	/// Destructor
  virtual ~AliMUONTrackExtrap(){};
  
  static void SetField();
  
  /// return kTRUE if the field is switched ON
  static Bool_t IsFieldON() {return fgFieldON;}
  
  static Double_t GetImpactParamFromBendingMomentum(Double_t bendingMomentum);
  static Double_t GetBendingMomentumFromImpactParam(Double_t impactParam);
  
  // Linearly extrapolate track parameters and covariances
  static void LinearExtrapToZ(AliMUONTrackParam* trackParam, Double_t zEnd, Bool_t updatePropagator = kFALSE);
  
  // Extrapolate track parameters in magnetic field
  static void ExtrapToZ(AliMUONTrackParam *trackParam, Double_t zEnd);
  
  // Extrapolate track parameters and covariances in magnetic field
  static void ExtrapToZCov(AliMUONTrackParam* trackParam, Double_t zEnd, Bool_t updatePropagator = kFALSE);
  
  // Extrapolate track parameters to vertex, corrected for multiple scattering and energy loss effects
  // Add branson correction resolution and energy loss fluctuation to parameter covariances
  static void ExtrapToVertex(AliMUONTrackParam* trackParam,
                             Double_t xVtx, Double_t yVtx, Double_t zVtx,
                             Double_t errXVtx, Double_t errYVtx);
  
  // Extrapolate track parameters to vertex, corrected for multiple scattering effects only
  // Add branson correction resolution to parameter covariances
  static void ExtrapToVertexWithoutELoss(AliMUONTrackParam* trackParam,
					 Double_t xVtx, Double_t yVtx, Double_t zVtx,
					 Double_t errXVtx, Double_t errYVtx);
  
  // Extrapolate track parameters to vertex, corrected for energy loss effects only
  // Add dispersion due to multiple scattering and energy loss fluctuation to parameter covariances
  static void ExtrapToVertexWithoutBranson(AliMUONTrackParam* trackParam, Double_t zVtx);
  
  // Extrapolate track parameters to vertex without multiple scattering and energy loss corrections
  // Add dispersion due to multiple scattering to parameter covariances
  static void ExtrapToVertexUncorrected(AliMUONTrackParam* trackParam, Double_t zVtx);
  
  static Double_t TotalMomentumEnergyLoss(AliMUONTrackParam* trackParam, Double_t xVtx, Double_t yVtx, Double_t zVtx);
  
  static Double_t GetMCSAngle2(const AliMUONTrackParam& param, Double_t dZ, Double_t x0);
  static void     AddMCSEffect(AliMUONTrackParam *param, Double_t dZ, Double_t x0);
  
  static void ExtrapOneStepRungekutta(Double_t charge, Double_t step, Double_t* vect, Double_t* vout);
  
  
 private:
  static const Double_t fgkSimpleBPosition;     //!< position of the dipole
  static const Double_t fgkSimpleBLength;       //!< length of the dipole
  static       Double_t fgSimpleBValue;         //!< magnetic field value at the centre
  static       Bool_t   fgFieldON;              //!< kTRUE if the field is switched ON
  static const Bool_t   fgkUseHelix;		//!< Tell whether to use Helix or not (default is Runge-Kutta)
  static const Int_t    fgkMaxStepNumber;	//!< Maximum number of steps for track extrapolation
  static const Double_t fgkHelixStepLength;	//!< Step lenght for track extrapolation (used in Helix)
  static const Double_t fgkRungeKuttaMaxResidue;//!< Maximal distance (in Z) to destination to stop the track extrapolation (used in Runge-Kutta)
  
  // Functions

  /// Not implemented
  AliMUONTrackExtrap(const AliMUONTrackExtrap& trackExtrap);
  /// Not implemented
  AliMUONTrackExtrap& operator=(const AliMUONTrackExtrap& trackExtrap);

  static void ExtrapToZHelix(AliMUONTrackParam *trackParam, Double_t Z);
  static void ExtrapToZRungekutta(AliMUONTrackParam *trackParam, Double_t Z);
  
  static void ConvertTrackParamForExtrap(AliMUONTrackParam* trackParam, Double_t forwardBackward, Double_t *v3);
  static void RecoverTrackParam(Double_t *v3, Double_t Charge, AliMUONTrackParam* trackParam);
  
  static void ExtrapToVertex(AliMUONTrackParam* trackParam,
                             Double_t xVtx, Double_t yVtx, Double_t zVtx,
                             Double_t errXVtx, Double_t errYVtx,
                             Bool_t correctForMCS, Bool_t correctForEnergyLoss);
  
  static void AddMCSEffectInAbsorber(AliMUONTrackParam* trackParam, Double_t pathLength, Double_t f0, Double_t f1, Double_t f2);
  static void CorrectMCSEffectInAbsorber(AliMUONTrackParam* param,
                                         Double_t xVtx, Double_t yVtx, Double_t zVtx,
                                         Double_t errXVtx, Double_t errYVtx,
                                         Double_t absZBeg, Double_t pathLength, Double_t f0, Double_t f1, Double_t f2);
  static void CorrectELossEffectInAbsorber(AliMUONTrackParam* param, Double_t eLoss, Double_t sigmaELoss2);
  static Bool_t GetAbsorberCorrectionParam(Double_t trackXYZIn[3], Double_t trackXYZOut[3], Double_t pTotal,
                                           Double_t &pathLength, Double_t &f0, Double_t &f1, Double_t &f2,
                                           Double_t &meanRho, Double_t &totalELoss, Double_t &sigmaELoss2);
  
  static Double_t BetheBloch(Double_t pTotal, Double_t pathLength, Double_t rho, Double_t atomicA, Double_t atomicZ);
  static Double_t EnergyLossFluctuation2(Double_t pTotal, Double_t pathLength, Double_t rho, Double_t atomicA, Double_t atomicZ);
  
  static void Cov2CovP(const TMatrixD &param, TMatrixD &cov);
  static void CovP2Cov(const TMatrixD &param, TMatrixD &cov);
  
  static void ExtrapOneStepHelix(Double_t charge, Double_t step, Double_t *vect, Double_t *vout);
  static void ExtrapOneStepHelix3(Double_t field, Double_t step, Double_t *vect, Double_t *vout);
  
  ClassDef(AliMUONTrackExtrap, 0) // Tools for track extrapolation in ALICE dimuon spectrometer
};
	
#endif
Commit	Line	Data
c04e3238	1	#ifndef ALIMUONTRACKEXTRAP_H
	2	#define ALIMUONTRACKEXTRAP_H
	3	/* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
	4	* See cxx source for full Copyright notice */
	5
	6	/$Id$/
	7	// Revision of includes 07/05/2004
	8
	9	/// \ingroup rec
	10	/// \class AliMUONTrackExtrap
	11	/// \brief Track parameters in ALICE dimuon spectrometer
	12	///
	13	//////////////////////////////////////////////////////////////
	14	/// Tools for track extrapolation in ALICE dimuon spectrometer
	15	//////////////////////////////////////////////////////////////
	16
	17	#include <TObject.h>
690d2205	18	#include <TMatrixD.h>
c04e3238	19
	20	class AliMagF;
	21	class AliMUONTrackParam;
	22
	23	class AliMUONTrackExtrap : public TObject
	24	{
	25	public:
	26	/// Constructor
	27	AliMUONTrackExtrap() : TObject(){};
	28	/// Destructor
	29	virtual ~AliMUONTrackExtrap(){};
	30
f7a1cc68	31	static void SetField();
9f093251	32
	33	/// return kTRUE if the field is switched ON
	34	static Bool_t IsFieldON() {return fgFieldON;}
c04e3238	35
208f139e	36	static Double_t GetImpactParamFromBendingMomentum(Double_t bendingMomentum);
	37	static Double_t GetBendingMomentumFromImpactParam(Double_t impactParam);
	38
690d2205	39	// Linearly extrapolate track parameters and covariances
9f093251	40	static void LinearExtrapToZ(AliMUONTrackParam* trackParam, Double_t zEnd, Bool_t updatePropagator = kFALSE);
690d2205	41
690d2205	42	// Extrapolate track parameters in magnetic field
019df241	43	static void ExtrapToZ(AliMUONTrackParam *trackParam, Double_t zEnd);
690d2205	44
690d2205	45	// Extrapolate track parameters and covariances in magnetic field
ea94c18b	46	static void ExtrapToZCov(AliMUONTrackParam* trackParam, Double_t zEnd, Bool_t updatePropagator = kFALSE);
690d2205	47
	48	// Extrapolate track parameters to vertex, corrected for multiple scattering and energy loss effects
	49	// Add branson correction resolution and energy loss fluctuation to parameter covariances
	50	static void ExtrapToVertex(AliMUONTrackParam* trackParam,
	51	Double_t xVtx, Double_t yVtx, Double_t zVtx,
	52	Double_t errXVtx, Double_t errYVtx);
	53
	54	// Extrapolate track parameters to vertex, corrected for multiple scattering effects only
	55	// Add branson correction resolution to parameter covariances
	56	static void ExtrapToVertexWithoutELoss(AliMUONTrackParam* trackParam,
	57	Double_t xVtx, Double_t yVtx, Double_t zVtx,
	58	Double_t errXVtx, Double_t errYVtx);
	59
	60	// Extrapolate track parameters to vertex, corrected for energy loss effects only
	61	// Add dispersion due to multiple scattering and energy loss fluctuation to parameter covariances
	62	static void ExtrapToVertexWithoutBranson(AliMUONTrackParam* trackParam, Double_t zVtx);
	63
	64	// Extrapolate track parameters to vertex without multiple scattering and energy loss corrections
	65	// Add dispersion due to multiple scattering to parameter covariances
208f139e	66	static void ExtrapToVertexUncorrected(AliMUONTrackParam* trackParam, Double_t zVtx);
fac70e25	67
fac70e25	68	static Double_t TotalMomentumEnergyLoss(AliMUONTrackParam* trackParam, Double_t xVtx, Double_t yVtx, Double_t zVtx);
c04e3238	69
ea94c18b	70	static Double_t GetMCSAngle2(const AliMUONTrackParam& param, Double_t dZ, Double_t x0);
ea94c18b	71	static void AddMCSEffect(AliMUONTrackParam *param, Double_t dZ, Double_t x0);
208f139e	72
c04e3238	73	static void ExtrapOneStepRungekutta(Double_t charge, Double_t step, Double_t* vect, Double_t* vout);
	74
	75
	76	private:
9f093251	77	static const Double_t fgkSimpleBPosition; //!< position of the dipole
	78	static const Double_t fgkSimpleBLength; //!< length of the dipole
	79	static Double_t fgSimpleBValue; //!< magnetic field value at the centre
	80	static Bool_t fgFieldON; //!< kTRUE if the field is switched ON
4284483e	81	static const Bool_t fgkUseHelix; //!< Tell whether to use Helix or not (default is Runge-Kutta)
	82	static const Int_t fgkMaxStepNumber; //!< Maximum number of steps for track extrapolation
	83	static const Double_t fgkHelixStepLength; //!< Step lenght for track extrapolation (used in Helix)
	84	static const Double_t fgkRungeKuttaMaxResidue;//!< Maximal distance (in Z) to destination to stop the track extrapolation (used in Runge-Kutta)
	85
c04e3238	86	// Functions
71a2d3aa	87
71a2d3aa	88	/// Not implemented
c04e3238	89	AliMUONTrackExtrap(const AliMUONTrackExtrap& trackExtrap);
71a2d3aa	90	/// Not implemented
c04e3238	91	AliMUONTrackExtrap& operator=(const AliMUONTrackExtrap& trackExtrap);
c04e3238	92
4284483e	93	static void ExtrapToZHelix(AliMUONTrackParam *trackParam, Double_t Z);
	94	static void ExtrapToZRungekutta(AliMUONTrackParam *trackParam, Double_t Z);
	95
	96	static void ConvertTrackParamForExtrap(AliMUONTrackParam* trackParam, Double_t forwardBackward, Double_t *v3);
eb3178e9	97	static void RecoverTrackParam(Double_t v3, Double_t Charge, AliMUONTrackParam trackParam);
c04e3238	98
690d2205	99	static void ExtrapToVertex(AliMUONTrackParam* trackParam,
	100	Double_t xVtx, Double_t yVtx, Double_t zVtx,
	101	Double_t errXVtx, Double_t errYVtx,
	102	Bool_t correctForMCS, Bool_t correctForEnergyLoss);
	103
8cde4af5	104	static void AddMCSEffectInAbsorber(AliMUONTrackParam* trackParam, Double_t pathLength, Double_t f0, Double_t f1, Double_t f2);
690d2205	105	static void CorrectMCSEffectInAbsorber(AliMUONTrackParam* param,
	106	Double_t xVtx, Double_t yVtx, Double_t zVtx,
	107	Double_t errXVtx, Double_t errYVtx,
	108	Double_t absZBeg, Double_t pathLength, Double_t f0, Double_t f1, Double_t f2);
	109	static void CorrectELossEffectInAbsorber(AliMUONTrackParam* param, Double_t eLoss, Double_t sigmaELoss2);
18abc511	110	static Bool_t GetAbsorberCorrectionParam(Double_t trackXYZIn[3], Double_t trackXYZOut[3], Double_t pTotal,
	111	Double_t &pathLength, Double_t &f0, Double_t &f1, Double_t &f2,
	112	Double_t &meanRho, Double_t &totalELoss, Double_t &sigmaELoss2);
8cde4af5	113
84f061ef	114	static Double_t BetheBloch(Double_t pTotal, Double_t pathLength, Double_t rho, Double_t atomicA, Double_t atomicZ);
690d2205	115	static Double_t EnergyLossFluctuation2(Double_t pTotal, Double_t pathLength, Double_t rho, Double_t atomicA, Double_t atomicZ);
	116
	117	static void Cov2CovP(const TMatrixD &param, TMatrixD &cov);
	118	static void CovP2Cov(const TMatrixD &param, TMatrixD &cov);
c04e3238	119
	120	static void ExtrapOneStepHelix(Double_t charge, Double_t step, Double_t vect, Double_t vout);
	121	static void ExtrapOneStepHelix3(Double_t field, Double_t step, Double_t vect, Double_t vout);
c04e3238	122
	123	ClassDef(AliMUONTrackExtrap, 0) // Tools for track extrapolation in ALICE dimuon spectrometer
	124	};
	125
	126	#endif