From b56a4c3ac6d52e9a984f46d5b20f0338ac980b52 Mon Sep 17 00:00:00 2001
From: jikim1290 <jikim1290@gmail.com>
Date: Mon, 3 Aug 2026 15:35:34 +0900
Subject: [PATCH] add rapidity selection for rotational bkg

---
 PWGLF/Tasks/Strangeness/lambdalambda.cxx | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/PWGLF/Tasks/Strangeness/lambdalambda.cxx b/PWGLF/Tasks/Strangeness/lambdalambda.cxx
index 2a861ea7ac9..47ba728a94a 100644
--- a/PWGLF/Tasks/Strangeness/lambdalambda.cxx
+++ b/PWGLF/Tasks/Strangeness/lambdalambda.cxx
@@ -527,6 +527,9 @@ struct lambdalambda {
                 RanPhi += RecoV02.Phi();
                 RecoV02Rot = ROOT::Math::PxPyPzMVector(RecoV02.Pt() * std::cos(RanPhi), RecoV02.Pt() * std::sin(RanPhi), RecoV02.Pz(), RecoV02.M());
                 RecoV0V0Rot = RecoV01 + RecoV02Rot;
+                if (std::abs(RecoV0V0Rot.Rapidity()) > cfgV0V0RapMax)
+                  continue;
+
                 histos.fill(HIST("h_InvMass_rot"), RecoV0V0Rot.M(), RecoV0V0Rot.Pt(), centrality, V01Tag + V02Tag);
               }
             }