[PWGCF] Updating to allow for a minimum cut value in multiplicity (#8574)

Author: coppedis

PWGCF/TableProducer/filterCorrelations.cxx

@@ -63,6 +63,7 @@ struct FilterCF {
   O2_DEFINE_CONFIGURABLE(cfgCollisionFlags, uint16_t, aod::collision::CollisionFlagsRun2::Run2VertexerTracks, "Request collision flags if non-zero (0 = off, 1 = Run2VertexerTracks)")
   O2_DEFINE_CONFIGURABLE(cfgTransientTables, bool, false, "Output transient tables for collision and track IDs")
   O2_DEFINE_CONFIGURABLE(cfgTrackSelection, int, 0, "Type of track selection (0 = Run 2/3 without systematics | 1 = Run 3 with systematics)")
+  O2_DEFINE_CONFIGURABLE(cfgMinMultiplicity, float, -1, "Minimum multiplicity considered for filtering (if value positive)")
 
   // Filters and input definitions
   Filter collisionZVtxFilter = nabs(aod::collision::posZ) < cfgCutVertex;
@@ -92,22 +93,26 @@ struct FilterCF {
   template <typename TCollision>
   bool keepCollision(TCollision& collision)
   {
+    bool isMultSelected = false;
+    if (collision.multiplicity() >= cfgMinMultiplicity)
+      isMultSelected = true;
+
     if (cfgTrigger == 0) {
       return true;
     } else if (cfgTrigger == 7) {
-      return collision.alias_bit(kINT7) && collision.sel7();
+      return isMultSelected && collision.alias_bit(kINT7) && collision.sel7();
     } else if (cfgTrigger == 8) {
-      return collision.sel8();
+      return isMultSelected && collision.sel8();
     } else if (cfgTrigger == 9) { // relevant only for Pb-Pb
-      return collision.sel8() && collision.selection_bit(aod::evsel::kNoSameBunchPileup) && collision.selection_bit(aod::evsel::kIsGoodZvtxFT0vsPV);
+      return isMultSelected && collision.sel8() && collision.selection_bit(aod::evsel::kNoSameBunchPileup) && collision.selection_bit(aod::evsel::kIsGoodZvtxFT0vsPV);
     } else if (cfgTrigger == 10) { // TVX trigger only (sel8 selection before April, 2024)
-      return collision.selection_bit(aod::evsel::kIsTriggerTVX);
+      return isMultSelected && collision.selection_bit(aod::evsel::kIsTriggerTVX);
     } else if (cfgTrigger == 11) { // sel8 selection for MC
-      return collision.selection_bit(aod::evsel::kIsTriggerTVX) && collision.selection_bit(aod::evsel::kNoTimeFrameBorder);
+      return isMultSelected && collision.selection_bit(aod::evsel::kIsTriggerTVX) && collision.selection_bit(aod::evsel::kNoTimeFrameBorder);
     } else if (cfgTrigger == 12) { // relevant only for Pb-Pb with occupancy cuts and rejection of the collisions which have other events nearby
       int occupancy = collision.trackOccupancyInTimeRange();
       if (occupancy >= 0 && occupancy < 500)
-        return collision.sel8() && collision.selection_bit(aod::evsel::kNoSameBunchPileup) && collision.selection_bit(aod::evsel::kIsGoodZvtxFT0vsPV) && collision.selection_bit(aod::evsel::kNoCollInTimeRangeStandard);
+        return isMultSelected && collision.sel8() && collision.selection_bit(aod::evsel::kNoSameBunchPileup) && collision.selection_bit(aod::evsel::kIsGoodZvtxFT0vsPV) && collision.selection_bit(aod::evsel::kNoCollInTimeRangeStandard);
       else
         return false;
     }