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4 * Author: The ALICE Off-line Project. *
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14 **************************************************************************/
18 //*-- Author: Andreas Morsch (CERN)
20 #include "AliEMCALFast.h"
24 ClassImp(AliEMCALFast)
26 //____________________________________________________________________________
29 Float_t AliEMCALFast::SmearMomentum(Int_t ind, Float_t p)
32 // The relative momentum error, i.e. (delta p)/p = sqrt (a**2 + (b*p)**2) *
34 // where typically a = 0.75 and b = 0.16 - 0.24 depending on multiplicity
35 // (the lower value is for dn/d(eta) about 2000, and the higher one for 8000)
40 if (ind == 2) b = 0.16;
42 Float_t sigma = p*TMath::Sqrt(a*a+b*b*p*p)*0.01;
43 pSmeared = p + gRandom->Gaus(0., sigma);
48 Float_t AliEMCALFast::Efficiency(Int_t ind, Float_t p)
50 // Tracking efficiency:
51 // above pt 0.5 GeV practically constant, between 90 and 95 % (agian,
52 // depending on multplicity)
53 // below 0.5 GeV goes down to about 70% at 0.2 GeV.
54 // On top of that there is 90% geometrical acceptance for tracking due
55 // to TPC (dead zones between readout chambers).
60 if (ind == 2) eff = 0.95;
62 eff = eff-(0.5-p)*0.2/0.3;