PWGCF: FemtoUniverse -- Added V0-V0 combination and clean pair check (#5133)

* Added V0-V0 combination and clean pair check

* clang format fix

---------

Co-authored-by: Shirajum Monira <shirajum.monira@cernch>

Author: Eloviyo

PWGCF/FemtoUniverse/Core/FemtoUniversePairCleaner.h

@@ -84,6 +84,22 @@ class FemtoUniversePairCleaner
         return false;
       }
       return part1.globalIndex() != part2.globalIndex();
+    } else if constexpr (mPartOneType == o2::aod::femtouniverseparticle::ParticleType::kV0 && mPartTwoType == o2::aod::femtouniverseparticle::ParticleType::kV0) {
+      /// V0-V0 combination both part1 and part2 are v0
+      if (part1.partType() != o2::aod::femtouniverseparticle::ParticleType::kV0 || part2.partType() != o2::aod::femtouniverseparticle::ParticleType::kV0) {
+        LOG(fatal) << "FemtoUniversePairCleaner: passed arguments don't agree with FemtoUniversePairCleaner instantiation! Please provide first and second arguments kV0 candidate.";
+        return false;
+      }
+      // Getting v0 children for part1
+      const auto& posChild1 = particles.iteratorAt(part1.index() - 2);
+      const auto& negChild1 = particles.iteratorAt(part1.index() - 1);
+      // Getting v0 children for part2
+      const auto& posChild2 = particles.iteratorAt(part2.index() - 2);
+      const auto& negChild2 = particles.iteratorAt(part2.index() - 1);
+      if (posChild1.globalIndex() == posChild2.globalIndex() || negChild1.globalIndex() == negChild2.globalIndex()) {
+        return false;
+      }
+      return part1.globalIndex() != part2.globalIndex();
     } else if constexpr (mPartOneType == o2::aod::femtouniverseparticle::ParticleType::kTrack && mPartTwoType == o2::aod::femtouniverseparticle::ParticleType::kD0) {
       /// Track-D0 combination part1 is hadron and part2 is D0
       if (part2.partType() != o2::aod::femtouniverseparticle::ParticleType::kD0) {

PWGCF/FemtoUniverse/Tasks/femtoUniversePairTaskTrackV0Extended.cxx

@@ -178,7 +178,7 @@ struct femtoUniversePairTaskTrackV0Extended {
       pairCloseRejection.init(&resultRegistry, &qaRegistry, ConfCPRdeltaPhiMax.value, ConfCPRdeltaEtaMax.value, ConfCPRdeltaPhiCut.value, ConfCPRdeltaEtaCut.value, ConfCPRPlotPerRadii.value);
     }
   }
-  /// This function processes the same event and takes care of all the histogramming
+  /// This function processes the same event for track - V0
   void processSameEvent(o2::aod::FDCollision& col, FemtoFullParticles& parts)
   {
     const auto& magFieldTesla = col.magField();
@@ -242,9 +242,53 @@ struct femtoUniversePairTaskTrackV0Extended {
     }
   }
 
-  PROCESS_SWITCH(femtoUniversePairTaskTrackV0Extended, processSameEvent, "Enable processing same event", true);
+  PROCESS_SWITCH(femtoUniversePairTaskTrackV0Extended, processSameEvent, "Enable processing same event for track - V0", false);
 
-  /// This function processes the mixed event
+  /// This function processes the same event for V0 - V0
+  void processSameEventV0(o2::aod::FDCollision& col, FemtoFullParticles& parts)
+  {
+    const auto& magFieldTesla = col.magField();
+
+    auto groupPartsTwo = partsTwo->sliceByCached(aod::femtouniverseparticle::fdCollisionId, col.globalIndex(), cache);
+    const int multCol = col.multNtr();
+
+    eventHisto.fillQA(col);
+
+    /// Histogramming same event
+    for (auto& part : groupPartsTwo) {
+      const auto& posChild = parts.iteratorAt(part.index() - 2);
+      const auto& negChild = parts.iteratorAt(part.index() - 1);
+      // printf("-- V0 d- %d d+ %d\n",negChild.globalIndex(),posChild.globalIndex());
+      if ((ConfV0Type > 0 && !IsParticleTPC(posChild, 0)) || (ConfV0Type < 0 && !IsParticleTPC(negChild, 0)))
+        continue;
+
+      trackHistoPartTwo.fillQA<false, false>(part);
+      posChildHistos.fillQA<false, false>(posChild);
+      negChildHistos.fillQA<false, false>(negChild);
+    }
+
+    /// Now build the combinations
+    for (auto& [p1, p2] : combinations(CombinationsFullIndexPolicy(groupPartsTwo, groupPartsTwo))) {
+      if (ConfIsCPR.value) {
+        if (pairCloseRejection.isClosePair(p1, p2, parts, magFieldTesla)) {
+          continue;
+        }
+      }
+      // track cleaning
+      if (!pairCleaner.isCleanPair(p1, p2, parts)) {
+        continue;
+      }
+      const auto& posChild = parts.iteratorAt(p2.index() - 2);
+      const auto& negChild = parts.iteratorAt(p2.index() - 1);
+      if ((ConfV0Type > 0 && !IsParticleTPC(posChild, 0)) || (ConfV0Type < 0 && !IsParticleTPC(negChild, 0)))
+        continue;
+      sameEventCont.setPair<false>(p1, p2, multCol, ConfUse3D);
+    }
+  }
+
+  PROCESS_SWITCH(femtoUniversePairTaskTrackV0Extended, processSameEventV0, "Enable processing same event for V0 - V0", false);
+
+  /// This function processes the mixed event for track - V0
   void processMixedEvent(o2::aod::FDCollisions& cols, FemtoFullParticles& parts)
   {
     ColumnBinningPolicy<aod::collision::PosZ, aod::femtouniversecollision::MultNtr> colBinning{{ConfVtxBins, ConfMultBins}, true};
@@ -285,7 +329,47 @@ struct femtoUniversePairTaskTrackV0Extended {
     }
   }
 
-  PROCESS_SWITCH(femtoUniversePairTaskTrackV0Extended, processMixedEvent, "Enable processing mixed events", true);
+  PROCESS_SWITCH(femtoUniversePairTaskTrackV0Extended, processMixedEvent, "Enable processing mixed events for track - V0", false);
+
+  /// This function processes the mixed event for V0 - V0
+  void processMixedEventV0(o2::aod::FDCollisions& cols, FemtoFullParticles& parts)
+  {
+    ColumnBinningPolicy<aod::collision::PosZ, aod::femtouniversecollision::MultNtr> colBinning{{ConfVtxBins, ConfMultBins}, true};
+
+    for (auto& [collision1, collision2] : soa::selfCombinations(colBinning, 5, -1, cols, cols)) {
+
+      const int multCol = collision1.multNtr();
+
+      auto groupPartsOne = partsOne->sliceByCached(aod::femtouniverseparticle::fdCollisionId, collision1.globalIndex(), cache);
+      auto groupPartsTwo = partsTwo->sliceByCached(aod::femtouniverseparticle::fdCollisionId, collision2.globalIndex(), cache);
+
+      const auto& magFieldTesla1 = collision1.magField();
+      const auto& magFieldTesla2 = collision2.magField();
+
+      if (magFieldTesla1 != magFieldTesla2) {
+        continue;
+      }
+
+      for (auto& [p1, p2] : combinations(CombinationsFullIndexPolicy(groupPartsTwo, groupPartsTwo))) {
+        if (ConfIsCPR.value) {
+          if (pairCloseRejection.isClosePair(p1, p2, parts, magFieldTesla1)) {
+            continue;
+          }
+        }
+        // track cleaning
+        if (!pairCleaner.isCleanPair(p1, p2, parts)) {
+          continue;
+        }
+        const auto& posChild = parts.iteratorAt(p2.index() - 2);
+        const auto& negChild = parts.iteratorAt(p2.index() - 1);
+        if ((ConfV0Type > 0 && !IsParticleTPC(posChild, 0)) || (ConfV0Type < 0 && !IsParticleTPC(negChild, 0)))
+          continue;
+        mixedEventCont.setPair<false>(p1, p2, multCol, ConfUse3D);
+      }
+    }
+  }
+
+  PROCESS_SWITCH(femtoUniversePairTaskTrackV0Extended, processMixedEventV0, "Enable processing mixed events for V0 - V0", false);
 };
 
 WorkflowSpec defineDataProcessing(ConfigContext const& cfgc)