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4 * Author: The ALICE Off-line Project. *
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14 **************************************************************************/
18 //____________________________________________________________________________
20 //*-- Author: Andreas Morsch (CERN)
23 ////////////////////////////////////////////////////////////////////////////
28 #include "AliEMCALFast.h"
31 ClassImp(AliEMCALFast)
33 //____________________________________________________________________________
36 Float_t AliEMCALFast::SmearMomentum(Int_t ind, Float_t p)
39 // The relative momentum error, i.e.
40 // (delta p)/p = sqrt (a**2 + (b*p)**2) * 10**-2,
41 // where typically a = 0.75 and b = 0.16 - 0.24 depending on multiplicity
42 // (the lower value is for dn/d(eta) about 2000, and the higher one for 8000)
44 // If we include information from TRD b will be by a factor 2/3 smaller.
46 // ind = 1: high multiplicity
47 // ind = 2: low multiplicity
48 // ind = 3: high multiplicity + TRD
49 // ind = 4: low multiplicity + TRD
55 if (ind == 1) b = 0.24;
56 if (ind == 2) b = 0.16;
57 if (ind == 3) b = 0.16;
58 if (ind == 4) b = 0.11;
60 Float_t sigma = p*TMath::Sqrt(a*a+b*b*p*p)*0.01;
61 pSmeared = p + gRandom->Gaus(0., sigma);
66 Float_t AliEMCALFast::Efficiency(Int_t ind, Float_t p)
68 // Tracking efficiency:
69 // above pt 0.5 GeV practically constant, between 90 and 95 % (again,
70 // depending on multplicity)
71 // below 0.5 GeV goes down to about 70% at 0.2 GeV.
72 // On top of that there is 90% geometrical acceptance for tracking due
73 // to TPC (dead zones between readout chambers).
77 if (ind == 2) eff = 0.95;
78 if (p < 0.5) eff -= (0.5-p)*0.2/0.3;
85 Bool_t AliEMCALFast::EmcalAcceptance(Float_t eta, Float_t phi)
88 // EMCAL eta-phi acceptance
90 if (TMath::Abs(eta) < 0.7 &&
91 phi > 60.*TMath::Pi()/180. &&
98 Bool_t AliEMCALFast::RandomReject(Float_t eff)
103 Float_t ran = gRandom->Rndm();
104 if (ran > eff) rej = kTRUE;