[PWGJE] eventWeight fix for fake collisions (AliceO2Group#10959)

Author: aimeric-landou

PWGJE/TableProducer/derivedDataProducer.cxx

@@ -241,12 +241,11 @@ struct JetDerivedDataProducerTask {
 
   void processMcCollisionLabels(soa::Join<aod::Collisions, aod::McCollisionLabels>::iterator const& collision, aod::McCollisions const&)
   {
+    products.jMcCollisionsLabelTable(collision.mcCollisionId()); // collision.mcCollisionId() returns -1 if collision has no associated mcCollision
     if (collision.has_mcCollision()) {
-      products.jMcCollisionsLabelTable(collision.mcCollisionId());
       products.jCollisionMcInfosTable(collision.mcCollision().weight(), collision.mcCollision().getSubGeneratorId());
     } else {
-      products.jMcCollisionsLabelTable(-1);
-      products.jCollisionMcInfosTable(-1.0, jetderiveddatautilities::JCollisionSubGeneratorId::none);
+      products.jCollisionMcInfosTable(0.0, jetderiveddatautilities::JCollisionSubGeneratorId::none);
     }
   }
   PROCESS_SWITCH(JetDerivedDataProducerTask, processMcCollisionLabels, "produces derived MC collision labels table", false);

PWGJE/TableProducer/jetEventWeightMCD.cxx

@@ -40,14 +40,14 @@ struct JetEventWeightMCDTask {
   void processMCDetectorLevelEventWeight(MCDetectorLevelJetTable const& jet, soa::Join<aod::JetCollisions, aod::JMcCollisionLbs> const&, aod::JetMcCollisions const&)
   {
     auto collision = jet.template collision_as<soa::Join<aod::JetCollisions, aod::JMcCollisionLbs>>();
-    mcDetectorLevelWeightsTable(jet.globalIndex(), collision.mcCollision().weight());
+    mcDetectorLevelWeightsTable(jet.globalIndex(), collision.weight());
   }
   PROCESS_SWITCH(JetEventWeightMCDTask, processMCDetectorLevelEventWeight, "Fill event weight tables for detector level MC jets", false);
 
   void processMCDetectorLevelEventWiseSubtractedEventWeight(MCDetectorLevelEventWiseSubtractedJetTable const& jet, soa::Join<aod::JetCollisions, aod::JMcCollisionLbs> const&, aod::JetMcCollisions const&)
   {
     auto collision = jet.template collision_as<soa::Join<aod::JetCollisions, aod::JMcCollisionLbs>>();
-    mcDetectorLevelEventWiseSubtractedWeightsTable(jet.globalIndex(), collision.mcCollision().weight());
+    mcDetectorLevelEventWiseSubtractedWeightsTable(jet.globalIndex(), collision.weight());
   }
   PROCESS_SWITCH(JetEventWeightMCDTask, processMCDetectorLevelEventWiseSubtractedEventWeight, "Fill event weight tables for detector level MC jets", false);
 };

PWGJE/Tasks/jetFinderQA.cxx

@@ -1191,7 +1191,7 @@ struct JetFinderQATask {
                              aod::JetMcCollisions const&,
                              soa::Filtered<soa::Join<aod::JetTracks, aod::JTrackExtras>> const& tracks)
   {
-    float eventWeight = collision.mcCollision().weight();
+    float eventWeight = collision.weight();
     if (skipMBGapEvents && collision.subGeneratorId() == jetderiveddatautilities::JCollisionSubGeneratorId::mbGap) {
       return;
     }

PWGJE/Tasks/jetSpectraCharged.cxx

@@ -552,10 +552,7 @@ struct JetSpectraCharged {
                          aod::JetMcCollisions const&,
                          soa::Filtered<soa::Join<aod::JetTracks, aod::JTrackExtras>> const& tracks)
   {
-    if (!collision.has_mcCollision()) { // the collision is fake and has no associated mc coll; skip as .mccollision() cannot be called
-      return;
-    }
-    float eventWeight = collision.mcCollision().weight();
+    float eventWeight = collision.weight();
     if (!jetderiveddatautilities::selectCollision(collision, eventSelectionBits, skipMBGapEvents)) {
       return;
     }
@@ -590,11 +587,10 @@ struct JetSpectraCharged {
   void processCollisionsWeighted(soa::Join<aod::JetCollisions, aod::JMcCollisionLbs>::iterator const& collision,
                                  aod::JetMcCollisions const&)
   {
-    if (!collision.has_mcCollision()) { // the collision is fake and has no associated mc coll; skip as .mccollision() cannot be called
+    if (!collision.has_mcCollision()) {
       registry.fill(HIST("h_fakecollisions"), 0.5);
-      return;
     }
-    float eventWeight = collision.mcCollision().weight();
+    float eventWeight = collision.weight();
     registry.fill(HIST("h_collisions"), 0.5);
     registry.fill(HIST("h_collisions_weighted"), 0.5, eventWeight);
     if (!jetderiveddatautilities::selectCollision(collision, eventSelectionBits, skipMBGapEvents)) {