[PWGHF] Add configurable for mixed event pair in correlatorHfeHadrons (#11591)

Co-authored-by: Rashi Gupta <rashi.gupta@cern.ch>

Author: rashigupt

PWGHF/HFC/TableProducer/correlatorHfeHadrons.cxx

@@ -54,6 +54,7 @@ struct HfCorrelatorHfeHadrons {
   Configurable<float> zPvPosMax{"zPvPosMax", 10., "Maximum z of the primary vertex (cm)"};
   Configurable<bool> isRun3{"isRun3", true, "Data is from Run3 or Run2"};
 
+  Configurable<int> numberEventsMixed{"numberEventsMixed", 5, "number of events mixed in ME process"};
   // Associated Hadron selection
   Configurable<float> ptTrackMin{"ptTrackMin", 0.1f, "Transverse momentum range for associated hadron tracks"};
   Configurable<float> etaTrackMax{"etaTrackMax", 0.8f, "Eta range  for associated hadron tracks"};
@@ -377,7 +378,7 @@ struct HfCorrelatorHfeHadrons {
   void processDataMixedEvent(TableCollisions const& collision, aod::HfCorrSelEl const& electron, TableTracks const& tracks)
   {
     auto tracksTuple = std::make_tuple(electron, tracks);
-    Pair<TableCollisions, aod::HfCorrSelEl, TableTracks, BinningType> pair{corrBinning, 5, -1, collision, tracksTuple, &cache};
+    Pair<TableCollisions, aod::HfCorrSelEl, TableTracks, BinningType> pair{corrBinning, numberEventsMixed, -1, collision, tracksTuple, &cache};
 
     // loop over the rows of the new table
     for (const auto& [c1, tracks1, c2, tracks2] : pair) {
@@ -392,7 +393,7 @@ struct HfCorrelatorHfeHadrons {
   void processMcRecMixedEvent(McTableCollisions const& mccollision, aod::HfCorrSelEl const& electron, McTableTracks const& mcTracks)
   {
     auto tracksTuple = std::make_tuple(electron, mcTracks);
-    Pair<McTableCollisions, aod::HfCorrSelEl, McTableTracks, BinningType> pairMcRec{corrBinning, 5, -1, mccollision, tracksTuple, &cache};
+    Pair<McTableCollisions, aod::HfCorrSelEl, McTableTracks, BinningType> pairMcRec{corrBinning, numberEventsMixed, -1, mccollision, tracksTuple, &cache};
 
     // loop over the rows of the new table
     for (const auto& [c1, tracks1, c2, tracks2] : pairMcRec) {

PWGHF/HFL/TableProducer/electronSelectionWithTpcEmcal.cxx

@@ -202,8 +202,9 @@ struct HfElectronSelectionWithTpcEmcal {
 
     registry.add("hAfterPIDEtaPhi", "PID Info after PID Cuts Eta vs Phi ; #eta; #varphi; ", {HistType::kTH2F, {{axisEta}, {axisPhi}}});
     registry.add("hEPRatioAfterPID", "E/P Ratio after PID Cuts apply only trackwodca filter", {HistType::kTH2F, {{axisPt}, {axisEmcEnergy}}});
-    registry.add("hPIDAfterPIDCuts", "PID Info after PID cuts; E/P;#it{p}_{T} (GeV#it{/c});n#sigma;m02; m20;", {HistType::kTHnSparseF, {{binsEoP}, {binsPt}, {binsnSigma}, {binsM02}, {binsM20}}});
-    registry.add("hEmcClsTrkEtaPhiDiffTime", "EmcClsTrkEtaPhiDiffTime;#Delta#eta;#Delta#varphi;Sec;", {HistType::kTH3F, {{binsDeltaEta}, {binsDeltaPhi}, {binsEmcClsTime}}});
+
+    registry.add("hPIDAfterPIDCuts", "PID Info after PID cuts; E/P;#it{p}_{T} (GeV#it{/c});n#sigma;m02; m20;", {HistType::kTHnSparseF, {{axisEoP}, {axisPt}, {axisnSigma}, {axisM02}, {axisM20}}});
+    registry.add("hEmcClsTrkEtaPhiDiffTime", "EmcClsTrkEtaPhiDiffTime;#Delta#eta;#Delta#varphi;Sec;", {HistType::kTH3F, {{axisDeltaEta}, {axisDeltaPhi}, {axisEmcClsTime}}});
   }
   // Track Selection Cut
   template <typename T>
@@ -365,6 +366,11 @@ struct HfElectronSelectionWithTpcEmcal {
       return;
 
     registry.fill(HIST("hNevents"), 1);
+
+    // skip events with no clusters
+    if (emcClusters.size() == 0) {
+      return;
+    }
     registry.fill(HIST("hZvertex"), collision.posZ());
 
     /////////////////////////////////