From f0032e5a7153ad6cdb03e92e0bfa8a122ceac9b1 Mon Sep 17 00:00:00 2001
From: rspijkers <rik.spijkers@gmail.com>
Date: Fri, 3 Oct 2025 15:20:36 +0200
Subject: [PATCH] add evsel at gen level

---
 PWGLF/Tasks/Strangeness/cascadecorrelations.cxx | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/PWGLF/Tasks/Strangeness/cascadecorrelations.cxx b/PWGLF/Tasks/Strangeness/cascadecorrelations.cxx
index 05d7c23b63d..56354e1502f 100644
--- a/PWGLF/Tasks/Strangeness/cascadecorrelations.cxx
+++ b/PWGLF/Tasks/Strangeness/cascadecorrelations.cxx
@@ -502,9 +502,14 @@ struct CascadeSelector {
 
   } // processCandidate
 
-  void processGenMC(aod::McCollision const&, soa::SmallGroups<soa::Join<aod::McCollisionLabels, MyCollisions>> const& collisions, aod::McParticles const& mcParticles)
+  void processGenMC(aod::McCollision const& mcCollision, soa::SmallGroups<soa::Join<aod::McCollisionLabels, MyCollisions>> const& collisions, aod::McParticles const& mcParticles)
   {
-    // N gen events without any event selection or matched reco event
+    // evsel
+    if (INEL < 0 || pwglf::isINELgtNmc(mcParticles, INEL, pdgDB))
+      return;
+    if (std::abs(mcCollision.posZ()) > maxVertexZ)
+      return;
+
     registry.fill(HIST("gen/hNevents"), 0);
 
     for (auto const& mcPart : mcParticles) {