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19 Revision 1.3.4.1 2003/07/07 14:13:31 schutz
22 Revision 1.4 2002/12/18 08:25:31 morsch
23 Correction in efficiency for p < 0.5.
25 Revision 1.3 2002/02/05 11:32:15 morsch
26 Smearing parameters with TRD included added.
28 Revision 1.2 2002/01/18 03:27:12 morsch
29 Acceptance and random rejection added.
34 //*-- Author: Andreas Morsch (CERN)
36 #include "AliEMCALFast.h"
40 ClassImp(AliEMCALFast)
42 //____________________________________________________________________________
45 Float_t AliEMCALFast::SmearMomentum(Int_t ind, Float_t p)
48 // The relative momentum error, i.e.
49 // (delta p)/p = sqrt (a**2 + (b*p)**2) * 10**-2,
50 // where typically a = 0.75 and b = 0.16 - 0.24 depending on multiplicity
51 // (the lower value is for dn/d(eta) about 2000, and the higher one for 8000)
53 // If we include information from TRD b will be by a factor 2/3 smaller.
55 // ind = 1: high multiplicity
56 // ind = 2: low multiplicity
57 // ind = 3: high multiplicity + TRD
58 // ind = 4: low multiplicity + TRD
64 if (ind == 1) b = 0.24;
65 if (ind == 2) b = 0.16;
66 if (ind == 3) b = 0.16;
67 if (ind == 4) b = 0.11;
69 Float_t sigma = p*TMath::Sqrt(a*a+b*b*p*p)*0.01;
70 pSmeared = p + gRandom->Gaus(0., sigma);
75 Float_t AliEMCALFast::Efficiency(Int_t ind, Float_t p)
77 // Tracking efficiency:
78 // above pt 0.5 GeV practically constant, between 90 and 95 % (again,
79 // depending on multplicity)
80 // below 0.5 GeV goes down to about 70% at 0.2 GeV.
81 // On top of that there is 90% geometrical acceptance for tracking due
82 // to TPC (dead zones between readout chambers).
86 if (ind == 2) eff = 0.95;
87 if (p < 0.5) eff -= (0.5-p)*0.2/0.3;
94 Bool_t AliEMCALFast::EmcalAcceptance(Float_t eta, Float_t phi)
97 // EMCAL eta-phi acceptance
99 if (TMath::Abs(eta) < 0.7 &&
101 phi < 120.*TMath::Pi()/180.)
107 Bool_t AliEMCALFast::RandomReject(Float_t eff)
112 Float_t ran = gRandom->Rndm();
113 if (ran > eff) rej = kTRUE;