Add occupancy cut to trackEfficiency task

1. Add occupancy cut to trackEfficiency.cxx for general purpose Pb-Pb MC 
2. Fix some cuts in weighted process functions

Author: wefeng1110

PWGJE/Tasks/jetSpectraCharged.cxx

@@ -549,7 +549,7 @@ struct JetSpectraCharged {
     if (!jetderiveddatautilities::selectCollision(collision, eventSelectionBits, skipMBGapEvents)) {
       return;
     }
-    if (collision.trackOccupancyInTimeRange() < trackOccupancyInTimeRangeMin || trackOccupancyInTimeRangeMax < collision.trackOccupancyInTimeRange()) {
+    if (std::abs(collision.posZ()) > vertexZCut) {
       return;
     }
     for (auto const& track : tracks) {
@@ -591,7 +591,7 @@ struct JetSpectraCharged {
     }
     registry.fill(HIST("h_collisions"), 1.5);
     registry.fill(HIST("h_collisions_weighted"), 1.5, eventWeight);
-    if (collision.trackOccupancyInTimeRange() < trackOccupancyInTimeRangeMin || trackOccupancyInTimeRangeMax < collision.trackOccupancyInTimeRange()) {
+    if (std::abs(collision.posZ()) > vertexZCut) {
       return;
     }
     registry.fill(HIST("h_collisions"), 2.5);
@@ -869,6 +869,7 @@ struct JetSpectraCharged {
     }
     registry.fill(HIST("h_mcColl_counts"), 2.5);
     registry.fill(HIST("h_mcColl_counts_weight"), 2.5, eventWeight);
+    registry.fill(HIST("h_mc_zvertex"), mccollision.posZ(), eventWeight);
 
     bool hasSel8Coll = false;
     for (auto const& collision : collisions) {

PWGJE/Tasks/trackEfficiency.cxx

@@ -53,6 +53,7 @@ struct TrackEfficiency {
   // Tracking efficiency process function configurables:
   Configurable<bool> checkPrimaryPart{"checkPrimaryPart", true, "0: doesn't check mcparticle.isPhysicalPrimary() - 1: checks particle.isPhysicalPrimary()"};
   Configurable<bool> checkCentrality{"checkCentrality", false, ""};
+  Configurable<bool> checkOccupancy{"checkOccupancy", false, "check occupancy only in general purpose Pb-Pb MC, default as false"};
   Configurable<int> acceptSplitCollisions{"acceptSplitCollisions", 0, "0: only look at mcCollisions that are not split; 1: accept split mcCollisions, 2: accept split mcCollisions but only look at the first reco collision associated with it"};
   Configurable<float> trackEtaAcceptanceCountQA{"trackEtaAcceptanceCountQA", 0.9, "eta acceptance"}; // removed from actual cuts for now because all the histograms have an eta axis
   Configurable<float> centralityMin{"centralityMin", -999, ""};
@@ -164,6 +165,9 @@ struct TrackEfficiency {
       registry.get<TH1>(HIST("hMcCollCutsCounts"))->GetXaxis()->SetBinLabel(5, "recoCollEvtSel");
       registry.get<TH1>(HIST("hMcCollCutsCounts"))->GetXaxis()->SetBinLabel(6, "centralityCut");
       registry.get<TH1>(HIST("hMcCollCutsCounts"))->GetXaxis()->SetBinLabel(7, "ptHatCut");
+      if(checkOccupancy){
+        registry.get<TH1>(HIST("hMcCollCutsCounts"))->GetXaxis()->SetBinLabel(8, "occupancyCut");
+      }
 
       registry.add("hMcPartCutsCounts", "McPart cuts count checks", {HistType::kTH1F, {{10, 0., 10.}}});
       registry.get<TH1>(HIST("hMcPartCutsCounts"))->GetXaxis()->SetBinLabel(1, "allPartsInSelMcColl");
@@ -315,13 +319,17 @@ struct TrackEfficiency {
 
     bool hasSel8Coll = false;
     bool centralityCheck = false;
+    bool occupancyCheck = false;
     if (acceptSplitCollisions == SplitOkCheckFirstAssocCollOnly || acceptSplitCollisions == NonSplitOnly) {    // check only that the first reconstructed collision passes the check (for the NonSplitOnly case, there's only one associated collision)
       if (jetderiveddatautilities::selectCollision(collisions.begin(), eventSelectionBits, skipMBGapEvents)) { // Skipping MC events that have not a single selected reconstructed collision ; effect unclear if mcColl is split
         hasSel8Coll = true;
       }
       if (!checkCentrality || ((centralityMin < collisions.begin().centrality()) && (collisions.begin().centrality() < centralityMax))) { // effect unclear if mcColl is split
         centralityCheck = true;
       }
+      if (!checkOccupancy || ((trackOccupancyInTimeRangeMin < collisions.begin().trackOccupancyInTimeRange()) && (collisions.begin().trackOccupancyInTimeRange() < trackOccupancyInTimeRangeMax))) { // check occupancy only in GP Pb-Pb MC
+        occupancyCheck = true;
+      }
     } else if (acceptSplitCollisions == SplitOkCheckAnyAssocColl) { // check that at least one of the reconstructed collisions passes the checks
       for (auto const& collision : collisions) {
         if (jetderiveddatautilities::selectCollision(collision, eventSelectionBits, skipMBGapEvents)) { // Skipping MC events that have not a single selected reconstructed collision ; effect unclear if mcColl is split
@@ -330,6 +338,9 @@ struct TrackEfficiency {
         if (!checkCentrality || ((centralityMin < collision.centrality()) && (collision.centrality() < centralityMax))) { // effect unclear if mcColl is split
           centralityCheck = true;
         }
+        if (!checkOccupancy || ((trackOccupancyInTimeRangeMin < collisions.begin().trackOccupancyInTimeRange()) && (collisions.begin().trackOccupancyInTimeRange() < trackOccupancyInTimeRangeMax))) { // check occupancy only in GP Pb-Pb MC
+          occupancyCheck = true;
+        }
       }
     }
     if (!hasSel8Coll) {
@@ -348,6 +359,13 @@ struct TrackEfficiency {
     }
     registry.fill(HIST("hMcCollCutsCounts"), 6.5); // ptHat condition
 
+    if(checkOccupancy){
+      if(!occupancyCheck){
+        return;
+      }
+      registry.fill(HIST("hMcCollCutsCounts"), 7.5);
+    }
+
     for (auto const& jMcParticle : jMcParticles) {
       registry.fill(HIST("hMcPartCutsCounts"), 0.5); // allPartsInSelMcColl