Bug fix. Distance from detector to vertex now calculated correctly

diff --git a/FMD/AliFMDBackgroundCorrection.cxx b/FMD/AliFMDBackgroundCorrection.cxx
index 17a5770cf60a00fa4a2aed8c66c9127e0ede540a..98818ac719e577bf5706645bc5dd6fa63acc71b9 100644 (file)
--- a/FMD/AliFMDBackgroundCorrection.cxx
+++ b/FMD/AliFMDBackgroundCorrection.cxx
@@ -312,8 +312,8 @@ AliFMDBackgroundCorrection::AliFMDInputBG::ProcessHit(AliFMDHit* h,
     return kTRUE;
   Bool_t retval = ProcessEvent(h->Detector(),
                               h->Ring(),
-                              h->Sector()
-                              ,h->Strip(),
+                              h->Sector(),
+                              h->Strip(),
                               h->Track(),
                               h->Q());
   
@@ -375,7 +375,7 @@ AliFMDBackgroundCorrection::AliFMDInputBG::ProcessEvent(UShort_t det,
     Float_t   phi   = TMath::ATan2(y,x);
     if(phi<0) phi   = phi+2*TMath::Pi();
     Float_t   r     = TMath::Sqrt(TMath::Power(x,2)+TMath::Power(y,2));
-    Float_t   theta = TMath::ATan2(r,z+vertex.At(2));
+    Float_t   theta = TMath::ATan2(r,z-vertex.At(2));
     Float_t   eta   = -1*TMath::Log(TMath::Tan(0.5*theta));
     hHits->Fill(eta,phi);
     fHits++;