adding two cuts (Markus H)

- the decay xy-radius for K0s, which I had simply forgotten last time,
- rejecting K0s invariant masses from proton samples/Lambda masses from pion samples.

diff --git a/PWG1/TRD/info/AliTRDv0Info.cxx b/PWG1/TRD/info/AliTRDv0Info.cxx
index cc71eed0d9071e6fe277a493a28849699a0dd84e..d2eb7839c53c05513244c127ddda59a0f88af2e1 100644 (file)
--- a/PWG1/TRD/info/AliTRDv0Info.cxx
+++ b/PWG1/TRD/info/AliTRDv0Info.cxx
@@ -551,20 +551,26 @@ Bool_t AliTRDv0Info::GetV0PID(Int_t ipart, AliTRDtrackInfo *track)
            continue;
          if(!(fQuality == 1))//... it fulfills our quality criteria
            continue;
-         if(!(fDCA < fUpDCA[iDecay]))//... distance of closest approach between daughters is reasonably small
+         if((fDCA > fUpDCA[iDecay]))//... distance of closest approach between daughters is reasonably small
            continue;
-         if(!(fPointingAngle < fUpPointingAngle[iDecay]))//... pointing angle between momentum of mother particle and vector from prim. to sec. vertex is small
+         if((fPointingAngle > fUpPointingAngle[iDecay]))//... pointing angle between momentum of mother particle and vector from prim. to sec. vertex is small
            continue;                             
-         if(!(fRadius > fDownRadius[iDecay]))//... x-y plane distance of decay point to prim. vertex is bigger than a certain minimum value (for conversions)
+         if((fRadius < fDownRadius[iDecay]))//... x-y plane distance of decay point to prim. vertex is bigger than a certain minimum value (for conversions)
            continue;
-         if(!(fOpenAngle < fUpOpenAngle[iDecay]))//... opening angle is close enough to zero (for conversions)
+         if((fRadius > fUpRadius[iDecay]))//...or smaller than a maximum value (for K0s)
            continue;
-         if(!(TMath::Abs(fPsiPair) < fUpPsiPair[iDecay]))//... Psi-pair angle is close enough to zero(for conversions)
+         if((fOpenAngle > fUpOpenAngle[iDecay]))//... opening angle is close enough to zero (for conversions)
+           continue;
+         if((TMath::Abs(fPsiPair) > fUpPsiPair[iDecay]))//... Psi-pair angle is close enough to zero(for conversions)
            continue;
 
          //specific cut criteria :
          if(ipart == AliPID::kProton)
-           {//for proton sample: separate treatment of Lamba and Anti-Lambda decays:
+           {
+             if((fInvMass[kK0s] < fUpInvMass[kK0s][iPSlot]) && (fInvMass[kK0s] > fDownInvMass[kK0s]))
+               continue;//explicit exclusion of K0s decays
+
+             //for proton sample: separate treatment of Lamba and Anti-Lambda decays:
              //for Anti-Lambda:
              //Combined PID likelihoods high enough for pi+ and anti-proton ; invariant mass calculated postulating these two particle species...
              if((fComPID[kNeg][AliPID::kProton] > fDownComPIDneg[AliPID::kProton]) && (fComPID[kPos][AliPID::kPion] > fDownComPIDposPart[AliPID::kPion]))
@@ -590,18 +596,25 @@ Bool_t AliTRDv0Info::GetV0PID(Int_t ipart, AliTRDtrackInfo *track)
                    }
                }
            }
+
          //Invariant mass cut for K0s and photons, assuming two pions/two electrons as daughters:
          if((fInvMass[iDecay] > fUpInvMass[iDecay][iPSlot]) || (fInvMass[iDecay] < fDownInvMass[iDecay]))
            continue;
          //for K0s decays: equal TPC PID likelihood criteria for both daughters ; invariant mass calculated postulating two pions
          if(ipart == AliPID::kPion)
            {
+             if((fInvMass[kLambda] < fUpInvMass[kLambda][iPSlot]) && (fInvMass[kLambda] > fDownInvMass[kLambda]))
+               continue;//explicit exclusion of Lambda decays
+             if((fInvMass[kAntiLambda] < fUpInvMass[kAntiLambda][iPSlot]) && (fInvMass[kAntiLambda] > fDownInvMass[kAntiLambda]))
+               continue;//explicit exclusion of Anti-Lambda decays
+
              if((fDetPID[kNeg][kTPC][ipart] > fDownTPCPIDneg[ipart]) && (fDetPID[kPos][kTPC][ipart] > fDownTPCPIDpos[ipart]))
                {
                  pid = 1;                                                
                }
            }
          //for photon conversions: equal combined PID likelihood criteria for both daughters ; invariant mass calculated postulating two electrons
+         //No Lambda/K0s exclusion is provided, since these contributions hardly ever interfere with gamma invariant mass!
          if(ipart == AliPID::kElectron)
            {
              if(fMomentum > 1.75)