Add BC based centrality

Author: abmodak

PWGLF/Tasks/GlobalEventProperties/heavyionMultiplicity.cxx

@@ -357,6 +357,23 @@ struct HeavyionMultiplicity {
       histos.add("hRecMCdndeta", "hRecMCdndeta", kTHnSparseD, {axisVtxZ, centAxis, axisOccupancy, axisEta, axisPhi, axisRecTrkType}, false);
       histos.add("etaResolution", "etaResolution", kTH2D, {axisEta, axisDeltaEta});
     }
+
+    if (doprocessBcData) {
+      histos.add("BcHist", "BcHist", kTH1D, {axisEvent}, false);
+      auto hstat = histos.get<TH1>(HIST("BcHist"));
+      auto* x = hstat->GetXaxis();
+      x->SetBinLabel(1, "All events");
+      x->SetBinLabel(2, "kIsTriggerTVX");
+      x->SetBinLabel(3, "kNoTimeFrameBorder");
+      x->SetBinLabel(4, "kNoITSROFrameBorder");
+      x->SetBinLabel(5, "kNoSameBunchPileup"); // reject collisions in case of pileup with another collision in the same foundBC
+      x->SetBinLabel(6, "kIsGoodZvtxFT0vsPV"); // small difference between z-vertex from PV and from FT0
+      x->SetBinLabel(7, "ApplyNoCollInTimeRangeStandard");
+      histos.add("BcCentFT0CHist", "BcCentFT0CHist", kTH1D, {axisCent}, false);
+      histos.add("BcCentFT0MHist", "BcCentFT0MHist", kTH1D, {axisCent}, false);
+      histos.add("CollCentFT0CHist", "CollCentFT0CHist", kTH1D, {axisCent}, false);
+      histos.add("CollCentFT0MHist", "CollCentFT0MHist", kTH1D, {axisCent}, false);
+    }
   }
 
   template <typename CheckCol>
@@ -402,6 +419,37 @@ struct HeavyionMultiplicity {
     return true;
   }
 
+  template <typename CheckBc>
+  bool isBCSelected(CheckBc const& bc)
+  {
+    histos.fill(HIST("BcHist"), 1);
+    if (!bc.selection_bit(o2::aod::evsel::kIsTriggerTVX)) {
+      return false;
+    }
+    histos.fill(HIST("BcHist"), 2);
+    if (isApplyTFcut && !bc.selection_bit(o2::aod::evsel::kNoTimeFrameBorder)) {
+      return false;
+    }
+    histos.fill(HIST("BcHist"), 3);
+    if (isApplyITSROcut && !bc.selection_bit(o2::aod::evsel::kNoITSROFrameBorder)) {
+      return false;
+    }
+    histos.fill(HIST("BcHist"), 4);
+    if (isApplySameBunchPileup && !bc.selection_bit(o2::aod::evsel::kNoSameBunchPileup)) {
+      return false;
+    }
+    histos.fill(HIST("BcHist"), 5);
+    if (isApplyGoodZvtxFT0vsPV && !bc.selection_bit(o2::aod::evsel::kIsGoodZvtxFT0vsPV)) {
+      return false;
+    }
+    histos.fill(HIST("BcHist"), 6);
+    if (isApplyNoCollInTimeRangeStandard && !bc.selection_bit(o2::aod::evsel::kNoCollInTimeRangeStandard)) {
+      return false;
+    }
+    histos.fill(HIST("BcHist"), 7);
+    return true;
+  }
+
   template <typename CheckColCent>
   float selColCent(CheckColCent const& col)
   {
@@ -971,6 +1019,29 @@ struct HeavyionMultiplicity {
     } // collision loop
   }
 
+  PresliceUnsorted<o2::soa::Join<o2::aod::Collisions, o2::aod::EvSels, aod::CentFT0Cs, aod::CentFT0Ms>> perFoundBC = aod::evsel::foundBCId;
+  void processBcData(soa::Join<aod::BCs, aod::BcSels, aod::Timestamps, aod::BCCentFT0Cs, aod::BCCentFT0Ms, aod::Run3MatchedToBCSparse> const& bcs, soa::Join<aod::Collisions, aod::EvSels, aod::PVMults, aod::CentFT0Cs, aod::CentFT0Ms> const& collisions)
+  {
+    for (const auto& bc : bcs) {
+      if (!isBCSelected(bc)) {
+        continue;
+      }
+      histos.fill(HIST("BcCentFT0CHist"), bc.centFT0C());
+      histos.fill(HIST("BcCentFT0MHist"), bc.centFT0M());
+      auto collisionsInBC = collisions.sliceBy(perFoundBC, bc.globalIndex());
+      for (const auto& collision : collisionsInBC) {
+        if (!isEventSelected(collision)) {
+          continue;
+        }
+        if (std::abs(collision.posZ()) >= vtxRange) {
+          continue;
+        }
+        histos.fill(HIST("CollCentFT0CHist"), collision.centFT0C());
+        histos.fill(HIST("CollCentFT0MHist"), collision.centFT0M());
+      } // collision table
+    } // bc table
+  }
+
   PROCESS_SWITCH(HeavyionMultiplicity, processData, "process data CentFT0C", false);
   PROCESS_SWITCH(HeavyionMultiplicity, processCorrelation, "do correlation study in data", false);
   PROCESS_SWITCH(HeavyionMultiplicity, processMonteCarlo, "process MC CentFT0C", false);
@@ -979,6 +1050,7 @@ struct HeavyionMultiplicity {
   PROCESS_SWITCH(HeavyionMultiplicity, processGen, "process pure MC gen", false);
   PROCESS_SWITCH(HeavyionMultiplicity, processEvtLossSigLossMC, "process Signal Loss, Event Loss", false);
   PROCESS_SWITCH(HeavyionMultiplicity, processMCeff, "process extra efficiency function", false);
+  PROCESS_SWITCH(HeavyionMultiplicity, processBcData, "process BC Centrality", false);
 };
 
 WorkflowSpec defineDataProcessing(ConfigContext const& cfgc)