[PWGJE] Add event count histograms (#11139)

Author: DonggukKim0

PWGJE/Tasks/dijetFinderQA.cxx

@@ -77,6 +77,7 @@ struct DijetFinderQATask {
   {
     eventSelection = jetderiveddatautilities::initialiseEventSelectionBits(static_cast<std::string>(eventSelections));
     trackSelection = jetderiveddatautilities::initialiseTrackSelection(static_cast<std::string>(trackSelections));
+    // Add histogram for event counts
 
     auto dijetMassTemp = 0.0;
     while (dijetMassTemp <= 2 * jetPtMax) {
@@ -85,17 +86,21 @@ struct DijetFinderQATask {
     }
 
     AxisSpec dijetMassAxis = {dijetMassBins, "M_{jj} (GeV/#it{c}^2)"};
+    AxisSpec eventCountAxis = {{0.5, 1.5}, "events"};
 
     if (doprocessDijetMCP) {
       registry.add("h_part_dijet_mass", "Dijet invariant mass;;entries", {HistType::kTH1F, {dijetMassAxis}});
+      registry.add("hColCounterFinal_MCP", "Event count;;entries", {HistType::kTH1F, {eventCountAxis}});
     }
 
     if (doprocessDijetMCD) {
       registry.add("h_detec_dijet_mass", "Dijet invariant mass;;entries", {HistType::kTH1F, {dijetMassAxis}});
+      registry.add("hColCounterFinal_MCD", "Event count;;entries", {HistType::kTH1F, {eventCountAxis}});
     }
 
     if (doprocessDijetData) {
       registry.add("h_data_dijet_mass", "Dijet invariant mass;;entries", {HistType::kTH1F, {dijetMassAxis}});
+      registry.add("hColCounterFinal_Data", "Event count;;entries", {HistType::kTH1F, {eventCountAxis}});
     }
 
     if (doprocessDijetMCMatched) {
@@ -175,8 +180,18 @@ struct DijetFinderQATask {
   }
   PROCESS_SWITCH(DijetFinderQATask, processDummy, "dummy", false);
 
-  void processDijetMCP(soa::Filtered<aod::JetMcCollisions>::iterator const&, soa::Filtered<aod::ChargedMCParticleLevelJets> const& jets)
+  void processDijetMCP(soa::Filtered<aod::JetMcCollisions>::iterator const&, soa::Filtered<aod::ChargedMCParticleLevelJets> const& jets, soa::SmallGroups<aod::JetCollisionsMCD> const& collisions)
   {
+    if (collisions.size() == 0) {
+      return;
+    }
+    for (auto& collision : collisions) {
+      if (fabs(collision.posZ()) > vertexZCut || !jetderiveddatautilities::selectCollision(collision, eventSelection))
+        return;
+    }
+
+    registry.fill(HIST("hColCounterFinal_MCP"), 1);
+
     std::vector<std::array<double, 3>> jetPtcuts;
     for (auto& jet : jets) {
       jetPtcuts.push_back({jet.pt(), jet.eta(), jet.phi()});
@@ -209,6 +224,9 @@ struct DijetFinderQATask {
     if (!jetderiveddatautilities::selectCollision(collision, eventSelection)) {
       return;
     }
+
+    registry.fill(HIST("hColCounterFinal_MCD"), 1);
+
     std::vector<std::array<double, 3>> jetPtcuts;
     for (auto& jet : jets) {
       jetPtcuts.push_back({jet.pt(), jet.eta(), jet.phi()});
@@ -242,6 +260,9 @@ struct DijetFinderQATask {
       return;
     }
 
+    // Fill event count histogram
+    registry.fill(HIST("hColCounterFinal_Data"), 1);
+
     std::vector<std::array<double, 3>> jetPtcuts;
     for (auto& jet : jets) {
       jetPtcuts.push_back({jet.pt(), jet.eta(), jet.phi()});