From ee4ef2b859b9b0a9240d232964b02b6ff1abf1f0 Mon Sep 17 00:00:00 2001
From: Seul I Jeong <tifa1289@gmail.com>
Date: Tue, 15 Sep 2026 21:08:28 +0900
Subject: [PATCH] [PWGHF] Add MC species templates for eID in
 taskSingleElectron

Add TPC nSigma(e) vs pT per MC truth species (e, pi, K, p, other) after track selection and after TOF selection, as templates for the eID fit.
---
 PWGHF/HFL/Tasks/taskSingleElectron.cxx | 50 ++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/PWGHF/HFL/Tasks/taskSingleElectron.cxx b/PWGHF/HFL/Tasks/taskSingleElectron.cxx
index cfe6e8434d5..3a66413094f 100644
--- a/PWGHF/HFL/Tasks/taskSingleElectron.cxx
+++ b/PWGHF/HFL/Tasks/taskSingleElectron.cxx
@@ -171,6 +171,18 @@ struct HfTaskSingleElectron {
     histos.add("hTpcNSigPtAfterTofCut", "", kTH2D, {{axisPtEl}, {axisNsig}});
     histos.add("hTpcNSigPtQA", "", kTH2D, {{axisPtEl}, {axisNsig}});
 
+    // TPC nSigma(e) vs pT per MC truth species (electron, pion, kaon, proton, other), after the track selection and after the TOF electron selection
+    histos.add("hTpcNSigPtRecElectron", "MC truth e^{#pm} after track selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtRecPion", "MC truth #pi^{#pm} after track selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtRecKaon", "MC truth K^{#pm} after track selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtRecProton", "MC truth p after track selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtRecOther", "MC truth other after track selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtAfterTofCutRecElectron", "MC truth e^{#pm} after TOF selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtAfterTofCutRecPion", "MC truth #pi^{#pm} after TOF selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtAfterTofCutRecKaon", "MC truth K^{#pm} after TOF selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtAfterTofCutRecProton", "MC truth p after TOF selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+    histos.add("hTpcNSigPtAfterTofCutRecOther", "MC truth other after TOF selection;#it{p}_{T} (GeV/#it{c});n#sigma_{e}^{TPC}", kTH2D, {{axisPtEl}, {axisNsig}});
+
     // track impact parameter
     histos.add("hDcaTrack", "", kTH2D, {{axisPtEl}, {axisTrackIp}});
     histos.add("hDcaBeauty", "", kTH2D, {{axisPtEl}, {axisTrackIp}});
@@ -205,6 +217,42 @@ struct HfTaskSingleElectron {
     histos.fill(HIST("hPtDcaZPreCut"), pt, track.dcaZ());
   }
 
+  template <typename TrackType>
+  void fillTpcNSigPtRec(const TrackType& track, bool afterTofCut)
+  {
+    if (!track.has_mcParticle()) {
+      return;
+    }
+    double const pt = track.pt();
+    double const nSigmaEl = track.tpcNSigmaEl();
+    int const absPdg = std::abs(track.mcParticle().pdgCode());
+    if (!afterTofCut) {
+      if (absPdg == kElectron) {
+        histos.fill(HIST("hTpcNSigPtRecElectron"), pt, nSigmaEl);
+      } else if (absPdg == kPiPlus) {
+        histos.fill(HIST("hTpcNSigPtRecPion"), pt, nSigmaEl);
+      } else if (absPdg == kKPlus) {
+        histos.fill(HIST("hTpcNSigPtRecKaon"), pt, nSigmaEl);
+      } else if (absPdg == kProton) {
+        histos.fill(HIST("hTpcNSigPtRecProton"), pt, nSigmaEl);
+      } else {
+        histos.fill(HIST("hTpcNSigPtRecOther"), pt, nSigmaEl);
+      }
+      return;
+    }
+    if (absPdg == kElectron) {
+      histos.fill(HIST("hTpcNSigPtAfterTofCutRecElectron"), pt, nSigmaEl);
+    } else if (absPdg == kPiPlus) {
+      histos.fill(HIST("hTpcNSigPtAfterTofCutRecPion"), pt, nSigmaEl);
+    } else if (absPdg == kKPlus) {
+      histos.fill(HIST("hTpcNSigPtAfterTofCutRecKaon"), pt, nSigmaEl);
+    } else if (absPdg == kProton) {
+      histos.fill(HIST("hTpcNSigPtAfterTofCutRecProton"), pt, nSigmaEl);
+    } else {
+      histos.fill(HIST("hTpcNSigPtAfterTofCutRecOther"), pt, nSigmaEl);
+    }
+  }
+
   template <typename TrackType>
   bool trackSel(const TrackType& track)
   {
@@ -566,6 +614,7 @@ struct HfTaskSingleElectron {
 
       histos.fill(HIST("hTofNSigPt"), track.pt(), track.tofNSigmaEl());
       histos.fill(HIST("hTpcNSigPt"), track.pt(), track.tpcNSigmaEl());
+      fillTpcNSigPtRec(track, false);
 
       int mpdg{};   // electron source pdg code
       double mpt{}; // electron source pt
@@ -599,6 +648,7 @@ struct HfTaskSingleElectron {
       }
       histos.fill(HIST("hTofNSigPtQA"), track.pt(), track.tofNSigmaEl());
       histos.fill(HIST("hTpcNSigPtAfterTofCut"), track.pt(), track.tpcNSigmaEl());
+      fillTpcNSigPtRec(track, true);
 
       if (track.tpcNSigmaEl() < nSigmaTpcMin || track.tpcNSigmaEl() > nSigmaTpcMax) {
         continue;