Fixes for the poisson method

diff --git a/PWG2/FORWARD/analysis2/AliFMDDensityCalculator.cxx b/PWG2/FORWARD/analysis2/AliFMDDensityCalculator.cxx
index 7d0a4bb4c8a920bb304cf47a403b5c418e20ed02..8320b9c6b71577d9bda5a420d92d64702cb39a9e 100644 (file)
--- a/PWG2/FORWARD/analysis2/AliFMDDensityCalculator.cxx
+++ b/PWG2/FORWARD/analysis2/AliFMDDensityCalculator.cxx
@@ -280,13 +280,11 @@ AliFMDDensityCalculator::Calculate(const AliESDFMD&        fmd,
          Float_t phi  = fmd.Phi(d,r,s,t) / 180 * TMath::Pi();
          Float_t eta  = fmd.Eta(d,r,s,t);
          rh->fTotalStrips->Fill(eta, phi);
-         if (mult < GetMultCut() || mult > 20) rh->fEmptyStrips->Fill(eta,phi);
-         if (mult == AliESDFMD::kInvalidMult || mult > 20) continue;
          
-         //if (mult == 0) { 
-         //  rh->fEmptyStrips->Fill(eta,phi);
-         //  continue;
-         // }
+         if (mult == AliESDFMD::kInvalidMult || mult > 20) { 
+           rh->fEmptyStrips->Fill(eta,phi);
+           continue;
+         }
          
          Float_t n   = NParticles(mult,d,r,s,t,vtxbin,eta,lowFlux);
          
@@ -323,11 +321,11 @@ AliFMDDensityCalculator::Calculate(const AliESDFMD&        fmd,
          // Mean in region of interest 
          Double_t poissonM = (total <= 0 || empty <= 0 ? 0 : 
                               -TMath::Log(empty / total));
-         Double_t poissonV = 0;
+         Double_t poissonV = hits;
          if(poissonM > 0)
            // Correct for counting statistics and weight by counts 
            poissonV = (hits * poissonM) / (1 - TMath::Exp(-1*poissonM));
-         Double_t poissonE = 0 ;
+         Double_t poissonE = TMath::Sqrt(hits);
          if(poissonV > 0) poissonE = TMath::Sqrt(poissonV);
          
          rh->fELossVsPoisson->Fill(eLossV, poissonV);