* provided "as is" without express or implied warranty. *
**************************************************************************/
-/*
-$Log$
-Revision 1.2 2000/06/30 12:07:50 kowal2
-Updated from the TPC-PreRelease branch
-
-Revision 1.1.2.2 2000/06/25 08:38:41 kowal2
-Splitted from AliTPCtracking
-
-*/
+/* $Id$ */
//-----------------------------------------------------------------
// Implementation of the TPC cluster class
ClassImp(AliTPCcluster)
+//____________________________________________________________________________
+Double_t AliTPCcluster::SigmaY2(Double_t r, Double_t tgl, Double_t pt)
+{
+ //
+ // Parametrised error of the cluster reconstruction (pad direction)
+ //
+ // Sigma rphi
+ const Float_t kArphi=0.41818e-2;
+ const Float_t kBrphi=0.17460e-4;
+ const Float_t kCrphi=0.30993e-2;
+ const Float_t kDrphi=0.41061e-3;
+
+ pt=TMath::Abs(pt)*1000.;
+ Double_t x=r/pt;
+ tgl=TMath::Abs(tgl);
+ Double_t s=kArphi - kBrphi*r*tgl + kCrphi*x*x + kDrphi*x;
+ if (s<0.4e-3) s=0.4e-3;
+ s*=1.3; //Iouri Belikov
+
+ return s;
+}
+
+
+//____________________________________________________________________________
+Double_t AliTPCcluster::SigmaZ2(Double_t r, Double_t tgl)
+{
+ //
+ // Parametrised error of the cluster reconstruction (drift direction)
+ //
+ // Sigma z
+ const Float_t kAz=0.39614e-2;
+ const Float_t kBz=0.22443e-4;
+ const Float_t kCz=0.51504e-1;
+
+
+ tgl=TMath::Abs(tgl);
+ Double_t s=kAz - kBz*r*tgl + kCz*tgl*tgl;
+ if (s<0.4e-3) s=0.4e-3;
+ s*=1.3; //Iouri Belikov
+
+ return s;
+}
+