Splitting TPC library (T.Kuhr)
[u/mrichter/AliRoot.git] / TPC / AliTPCcluster.cxx
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73042f01 1/**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
3 * *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
6 * *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
15
88cb7938 16/* $Id$ */
73042f01 17
18//-----------------------------------------------------------------
19// Implementation of the TPC cluster class
20//
21// Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
22//-----------------------------------------------------------------
23
24#include "AliTPCcluster.h"
25
26ClassImp(AliTPCcluster)
73042f01 27
6d75e4b6 28//____________________________________________________________________________
29Double_t AliTPCcluster::SigmaY2(Double_t r, Double_t tgl, Double_t pt)
30{
31 //
32 // Parametrised error of the cluster reconstruction (pad direction)
33 //
34 // Sigma rphi
35 const Float_t kArphi=0.41818e-2;
36 const Float_t kBrphi=0.17460e-4;
37 const Float_t kCrphi=0.30993e-2;
38 const Float_t kDrphi=0.41061e-3;
39
40 pt=TMath::Abs(pt)*1000.;
41 Double_t x=r/pt;
42 tgl=TMath::Abs(tgl);
43 Double_t s=kArphi - kBrphi*r*tgl + kCrphi*x*x + kDrphi*x;
44 if (s<0.4e-3) s=0.4e-3;
45 s*=1.3; //Iouri Belikov
46
47 return s;
48}
49
50
51//____________________________________________________________________________
52Double_t AliTPCcluster::SigmaZ2(Double_t r, Double_t tgl)
53{
54 //
55 // Parametrised error of the cluster reconstruction (drift direction)
56 //
57 // Sigma z
58 const Float_t kAz=0.39614e-2;
59 const Float_t kBz=0.22443e-4;
60 const Float_t kCz=0.51504e-1;
61
62
63 tgl=TMath::Abs(tgl);
64 Double_t s=kAz - kBz*r*tgl + kCz*tgl*tgl;
65 if (s<0.4e-3) s=0.4e-3;
66 s*=1.3; //Iouri Belikov
67
68 return s;
69}
70