PndHypAdvancedPidAlgo.h

Go to the documentation of this file.

#ifndef PndHypAdvancedPidAlgo_h
#define PndHypAdvancedPidAlgo_h

#include <math.h>
#include <map>
#include "Rtypes.h"

class PndHypPidCand;
class TRandom3;

class PndHypAdvancedPidAlgo {
public:


  //Local pid type (BABAR)
  enum {kNPidType = 5};
  enum PidType {
    kElectron,
    kMuon,
    kPion,
    kKaon,
    kProton
  };

  //Write likelihoods to PndHypPidCand
  static void CalcLikelihood(PndHypPidCand* cand);

  //Same as CalcLikelihood but create random energyloss first
  static void CalcLikelihood(PidType particle, double momentum, PndHypPidCand* cand);

  //Same as CalcLikelihood but write lhs to array instead
  static void CalcLikelihood(PidType part, double momentum, double* lh);

  //Same with a pdtid switch
  static void CalcLikelihood(int lundId, double momentum, double* lh);

  //Read last used energy loss and momentum
  static double GetMomentum() {return fmomentum;};
  static double GetEnergyLoss() {return fenergyloss;};

private:

  PndHypAdvancedPidAlgo(){};
  virtual ~PndHypAdvancedPidAlgo(){};
  static void CalcLikelihood(double* lh);

  //Expected energy loss, as given by Bethe-Bloch formula
  static double MeanEnergyLoss(PidType particle);

  //Integral algorithm that computes convolution of landau and gaus
  //distribution; s_mpv is the difference between energy loss and
  //most probable value of the landau distribution, width1 is its
  //scaling, widht2 is the gaussian width.
  static double LandauGaus(double s_mpv, double width1, double width2);

  //Obtained by TrkFitter
  static double fmomentum;
  static double fenergyloss;

  //Distribution parameters depending on track momentum and particle
  static double mpv(PidType particle);
  static double width1(PidType particle);
  static double width2(PidType particle);

  //Test: random generator for likelihoods
  static TRandom3* frand;

//public:
  ClassDef(PndHypAdvancedPidAlgo, 1);

};

#endif