Fix histogram names for processRun3 (AliceO2Group#948)

* fix histogram names for processRun3

minor

* Adjust filling scheme in v0 builder

Author: ercolessi

PWGLF/TableProducer/lambdakzerobuilder.cxx

@@ -428,7 +428,8 @@ struct lambdakzeroBuilder {
 #endif
       MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "V0 builder: found K0S from Lc, posTrack --> " << labelPos << ", negTrack --> " << labelNeg);
 
-      registry.fill(HIST("hGoodIndices"), 0.5);
+      //value 0.5: any considered V0
+      registry.fill(HIST("hV0Criteria"), 0.5);
       if (isRun2) {
         if (!(V0.posTrack_as<MyTracksIU>().trackType() & o2::aod::track::TPCrefit)) {
           MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "posTrack " << labelPos << " has no TPC refit");
@@ -441,7 +442,8 @@ struct lambdakzeroBuilder {
           continue; // TPC refit
         }
       }
-      registry.fill(HIST("hGoodIndices"), 1.5);
+      //Passes TPC refit
+      registry.fill(HIST("hV0Criteria"), 1.5);
       if (V0.posTrack_as<MyTracksIU>().tpcNClsCrossedRows() < mincrossedrows) {
         MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "posTrack " << labelPos << " has " << V0.posTrack_as<MyTracksIU>().tpcNClsCrossedRows() << " crossed rows, cut at " << mincrossedrows);
         v0dataLink(-1);
@@ -452,7 +454,8 @@ struct lambdakzeroBuilder {
         v0dataLink(-1);
         continue;
       }
-      registry.fill(HIST("hGoodIndices"), 2.5);
+      //passes crossed rows
+      registry.fill(HIST("hV0Criteria"), 2.5);
       if (fabs(V0.posTrack_as<MyTracksIU>().dcaXY()) < dcapostopv) {
         MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "posTrack " << labelPos << " has dcaXY " << V0.posTrack_as<MyTracksIU>().dcaXY() << " , cut at " << dcanegtopv);
         v0dataLink(-1);
@@ -464,7 +467,8 @@ struct lambdakzeroBuilder {
         continue;
       }
       MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "Filling good indices: posTrack --> " << labelPos << ", negTrack --> " << labelNeg);
-      registry.fill(HIST("hGoodIndices"), 3.5);
+      //passes DCAxy
+      registry.fill(HIST("hV0Criteria"), 3.5);
 
       // Candidate building part
       std::array<float, 3> pos = {0.};
@@ -479,8 +483,6 @@ struct lambdakzeroBuilder {
 
       MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "labelPos = " << labelPos << ", labelNeg = " << labelNeg);
 
-      registry.fill(HIST("hV0Candidate"), 0.5);
-
       auto pTrack = getTrackParCov(V0.posTrack_as<MyTracksIU>());
       auto nTrack = getTrackParCov(V0.negTrack_as<MyTracksIU>());
 
@@ -490,6 +492,9 @@ struct lambdakzeroBuilder {
         continue;
       }
 
+      //passes diff coll check
+      registry.fill(HIST("hV0Criteria"), 4.5);
+
       // Act on copies for minimization
       auto pTrackCopy = o2::track::TrackParCov(pTrack);
       auto nTrackCopy = o2::track::TrackParCov(nTrack);
@@ -502,6 +507,9 @@ struct lambdakzeroBuilder {
         continue;
       }
 
+      //passes V0 fitter minimization successfully
+      registry.fill(HIST("hV0Criteria"), 5.5);
+
       double finalXpos = fitter.getTrack(0).getX();
       double finalXneg = fitter.getTrack(1).getX();
 
@@ -525,6 +533,9 @@ struct lambdakzeroBuilder {
         continue;
       }
 
+      //Passes step 2 of V0 fitter
+      registry.fill(HIST("hV0Criteria"), 6.5);
+
       pTrack.getPxPyPzGlo(pvec0);
       nTrack.getPxPyPzGlo(pvec1);
 
@@ -542,23 +553,31 @@ struct lambdakzeroBuilder {
         continue;
       }
 
+      //Passes DCA between daughters check
+      registry.fill(HIST("hV0Criteria"), 7.5);
+
       auto V0CosinePA = RecoDecay::cpa(array{collision.posX(), collision.posY(), collision.posZ()}, array{pos[0], pos[1], pos[2]}, array{pvec0[0] + pvec1[0], pvec0[1] + pvec1[1], pvec0[2] + pvec1[2]});
       if (V0CosinePA < v0cospa) {
         MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "posTrack --> " << labelPos << ", negTrack --> " << labelNeg << " will be skipped due to CPA cut");
         v0dataLink(-1);
         continue;
       }
 
+      //Passes CosPA check
+      registry.fill(HIST("hV0Criteria"), 8.5);
+
       auto V0radius = RecoDecay::sqrtSumOfSquares(pos[0], pos[1]); // probably find better name to differentiate the cut from the variable
       if (V0radius < v0radius) {
         MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "posTrack --> " << labelPos << ", negTrack --> " << labelNeg << " will be skipped due to radius cut");
         v0dataLink(-1);
         continue;
       }
 
+      //Passes radius check
+      registry.fill(HIST("hV0Criteria"), 9.5);
+
       MY_DEBUG_MSG(isK0SfromLc, LOG(info) << "in builder 1, keeping K0S candidate: posTrack --> " << labelPos << ", negTrack --> " << labelNeg);
 
-      registry.fill(HIST("hV0Candidate"), 1.5);
       v0data(
         V0.posTrackId(),
         V0.negTrackId(),