From c43211e66502539b08c6e0d1c280e4b86e7fbec8 Mon Sep 17 00:00:00 2001
From: Stefanie Mrozinski <smrozins@cern.ch>
Date: Fri, 17 Apr 2026 08:51:59 +0200
Subject: [PATCH 1/2] Fix process function subscription

---
 PWGEM/PhotonMeson/Tasks/photonhbt.cxx | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/PWGEM/PhotonMeson/Tasks/photonhbt.cxx b/PWGEM/PhotonMeson/Tasks/photonhbt.cxx
index d7793efb694..3a698abb84b 100644
--- a/PWGEM/PhotonMeson/Tasks/photonhbt.cxx
+++ b/PWGEM/PhotonMeson/Tasks/photonhbt.cxx
@@ -93,8 +93,10 @@ using namespace o2::aod::pwgem::dilepton::utils;
 
 // EMMCEventLabels needed for processMC truth-efficiency loop
 using MyCollisions = soa::Join<aod::PMEvents, aod::EMEventsAlias, aod::EMEventsMult_000,
-                               aod::EMEventsCent_000, aod::EMEventsQvec_001,
-                               aod::EMMCEventLabels>;
+                               aod::EMEventsCent_000, aod::EMEventsQvec_001>;
+using MyCollisionsMC = soa::Join<aod::PMEvents, aod::EMEventsAlias, aod::EMEventsMult_000,
+                                 aod::EMEventsCent_000, aod::EMEventsQvec_001,
+                                 aod::EMMCEventLabels>;
 using MyCollision = MyCollisions::iterator;
 
 using MyV0Photons = soa::Join<aod::V0PhotonsKF, aod::V0KFEMEventIds, aod::V0PhotonsPhiVPsi>;
@@ -2279,6 +2281,8 @@ struct Photonhbt {
     o2::aod::evsel::ft0cOccupancyInTimeRange < eventcuts.cfgFT0COccupancyMax;
 
   using FilteredMyCollisions = soa::Filtered<MyCollisions>;
+  using FilteredMyMCCollisions = soa::Filtered<MyCollisionsMC>;
+
   int ndf = 0;
 
   void processAnalysis(FilteredMyCollisions const& collisions,
@@ -2291,7 +2295,8 @@ struct Photonhbt {
   }
   PROCESS_SWITCH(Photonhbt, processAnalysis, "pairing for analysis", true);
 
-  void processMC(FilteredMyCollisions const& collisions,
+  void processMC(FilteredMyMCCollisions const& mccollisions,
+                 FilteredMyCollisions const& collisions,
                  MyV0Photons const& v0photons,
                  MyMCV0Legs const& v0legs,
                  aod::EMMCParticles const& mcParticles,
@@ -2300,7 +2305,7 @@ struct Photonhbt {
 
     runPairingMC(collisions, v0photons, v0legs, mcParticles,
                  perCollisionPCM, fV0PhotonCut);
-    runTruthEfficiency(collisions, v0photons, v0legs, mcParticles, mcEvents,
+    runTruthEfficiency(mccollisions, v0photons, v0legs, mcParticles, mcEvents,
                        perMCCollisionEMMCParts, perCollisionV0Legs, fV0PhotonCut);
 
     ndf++;

From ac599a0c7e4346b45e87949d74765f6c22a32fc3 Mon Sep 17 00:00:00 2001
From: Stefanie Mrozinski <smrozins@cern.ch>
Date: Fri, 17 Apr 2026 13:15:27 +0200
Subject: [PATCH 2/2] Fix subscription in MC process function

---
 PWGEM/PhotonMeson/Tasks/photonhbt.cxx | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/PWGEM/PhotonMeson/Tasks/photonhbt.cxx b/PWGEM/PhotonMeson/Tasks/photonhbt.cxx
index 3a698abb84b..0abc24b3cad 100644
--- a/PWGEM/PhotonMeson/Tasks/photonhbt.cxx
+++ b/PWGEM/PhotonMeson/Tasks/photonhbt.cxx
@@ -91,7 +91,6 @@ using namespace o2::framework::expressions;
 using namespace o2::soa;
 using namespace o2::aod::pwgem::dilepton::utils;
 
-// EMMCEventLabels needed for processMC truth-efficiency loop
 using MyCollisions = soa::Join<aod::PMEvents, aod::EMEventsAlias, aod::EMEventsMult_000,
                                aod::EMEventsCent_000, aod::EMEventsQvec_001>;
 using MyCollisionsMC = soa::Join<aod::PMEvents, aod::EMEventsAlias, aod::EMEventsMult_000,
@@ -2296,14 +2295,13 @@ struct Photonhbt {
   PROCESS_SWITCH(Photonhbt, processAnalysis, "pairing for analysis", true);
 
   void processMC(FilteredMyMCCollisions const& mccollisions,
-                 FilteredMyCollisions const& collisions,
                  MyV0Photons const& v0photons,
                  MyMCV0Legs const& v0legs,
                  aod::EMMCParticles const& mcParticles,
                  aod::EMMCEvents const& mcEvents)
   {
 
-    runPairingMC(collisions, v0photons, v0legs, mcParticles,
+    runPairingMC(mccollisions, v0photons, v0legs, mcParticles,
                  perCollisionPCM, fV0PhotonCut);
     runTruthEfficiency(mccollisions, v0photons, v0legs, mcParticles, mcEvents,
                        perMCCollisionEMMCParts, perCollisionV0Legs, fV0PhotonCut);