From aa7ad8b89472b3217c3e078da37d7581fdfd3b8d Mon Sep 17 00:00:00 2001 From: aferrero2707 Date: Mon, 21 Sep 2026 17:44:53 +0200 Subject: [PATCH] [MUON] fix computation of delta phi in MFT-MCH matching The value of delta phi between the MFT and MCH tracks at the matching plane is restricted to the [-pi, pi] range, to fix the cases of large angular differences when the MFT and MCH tracks are at the opposite side of the horizontal plane at negative X values. --- Detectors/GlobalTracking/src/MatchGlobalFwd.cxx | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Detectors/GlobalTracking/src/MatchGlobalFwd.cxx b/Detectors/GlobalTracking/src/MatchGlobalFwd.cxx index 7ed50ce7400ae..58672d1f6886f 100644 --- a/Detectors/GlobalTracking/src/MatchGlobalFwd.cxx +++ b/Detectors/GlobalTracking/src/MatchGlobalFwd.cxx @@ -10,6 +10,7 @@ // or submit itself to any jurisdiction. #include "GlobalTracking/MatchGlobalFwd.h" +#include "MathUtils/Utils.h" #include using namespace o2::globaltracking; @@ -926,6 +927,9 @@ MatchGlobalFwd::MatchGlobalFwd() // Update Parameters r_k_kminus1 = m_k - H_k * GlobalMuonTrackParameters; // Residuals of prediction + // Restrict the phi residual to the [-pi, pi] range + o2::math_utils::bringToPMPiGend(r_k_kminus1[2]); + auto matchChi2Track = ROOT::Math::Similarity(r_k_kminus1, invResCov); return matchChi2Track; @@ -963,6 +967,9 @@ MatchGlobalFwd::MatchGlobalFwd() // Residuals of prediction r_k_kminus1 = m_k - H_k * GlobalMuonTrackParameters; + // Restrict the phi residual to the [-pi, pi] range + o2::math_utils::bringToPMPiGend(r_k_kminus1[2]); + auto matchChi2Track = ROOT::Math::Similarity(r_k_kminus1, invResCov); return matchChi2Track; };