bugfix: calculate Pterr with respect to magnetic field (Gaute)

[u/mrichter/AliRoot.git] / HLT / TPCLib / AliHLTTPCConfMapFit.cxx

diff --git a/HLT/TPCLib/AliHLTTPCConfMapFit.cxx b/HLT/TPCLib/AliHLTTPCConfMapFit.cxx
index 2bda0fa3d52cf699919c9ba122eae0e924313f8c..dc4f1ac9761fc53e37ed25a13436dfb44ecd9ff2 100644 (file)
--- a/HLT/TPCLib/AliHLTTPCConfMapFit.cxx
+++ b/HLT/TPCLib/AliHLTTPCConfMapFit.cxx
@@ -572,7 +572,9 @@ Int_t AliHLTTPCConfMapFit::FitLine ( )
   //Double_t Kms = (0.016/d)*TMath::Sqrt(lengthTot/24.0);
   Double_t Kms = 0.0;
 
-  Double_t Pterr = (Kres * Kres) + (Kms * Kms);
+  Double_t KTot = TMath::Sqrt((Kres * Kres) + (Kms * Kms));
+  
+  Double_t Pterr = (1/(0.3*AliHLTTPCTransform::GetBField()))*KTot;
 
   fTrack->SetPterr(Pterr);