bugfix to make the AliHLTDisplay working

[u/mrichter/AliRoot.git] / ITS / AliITSpidESD.cxx

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 * Author: The ALICE Off-line Project.                                    *
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//-----------------------------------------------------------------
//           Implementation of the ITS PID class
// Very naive one... Should be made better by the detector experts...
//      Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
//-----------------------------------------------------------------

#include <TMath.h>

#include "AliITSpidESD.h"
#include "AliESDtrack.h"

ClassImp(AliITSpidESD)


//______________________________________________________________________
AliITSpidESD::AliITSpidESD():TObject(){
  //Default constructor
 
}
Double_t AliITSpidESD::Bethe(Double_t bg) {
  //
  // This is the Bethe-Bloch function normalised to 1 at the minimum
  //
  Double_t bg2=bg*bg;
  Double_t bethe;
  /*if (bg<3.5) 
     bethe=(1.+ bg2)/bg2*(log(5940*bg2) - bg2/(1.+ bg2));
  else*/  // not 100% clear why...
  bethe=(1.+ bg2)/bg2*(TMath::Log(3.5*5940*bg) - bg2/(1.+ bg2));
  return bethe/11.091;
}