From 207398b393cb4c19617396561881bfc1a6f776f6 Mon Sep 17 00:00:00 2001
From: Anantha Padmanabhan M Nair
 <82643666+ananthapadmanabhan18@users.noreply.github.com>
Date: Tue, 17 Dec 2024 02:11:19 +0530
Subject: [PATCH] [PWGUD] Applied pT and y cuts to invariant mass distributions
 (#9013)

---
 PWGUD/Tasks/exclusiveRhoTo4Pi.cxx | 88 ++++++++++++++++++++++---------
 1 file changed, 63 insertions(+), 25 deletions(-)

diff --git a/PWGUD/Tasks/exclusiveRhoTo4Pi.cxx b/PWGUD/Tasks/exclusiveRhoTo4Pi.cxx
index 9d4cc4ca728..bb90337e371 100644
--- a/PWGUD/Tasks/exclusiveRhoTo4Pi.cxx
+++ b/PWGUD/Tasks/exclusiveRhoTo4Pi.cxx
@@ -82,27 +82,35 @@ struct UPCAnalysis {
     histos.add("tofNSigmaPi_WTS_PID_Pi", "TOF nSigma Pion with track selection and PID Selection of Pi; Entries", kTH1F, {{100, -15, 15}});
 
     // Track Transverse Momentum
-    histos.add("pT_track_WOTS", "pT without track selection; pT [GeV/c]; Events", kTH1F, {{100, 0, 2}});
-    histos.add("pT_track_WTS", "pT with track selection; pT [GeV/c]; Events", kTH1F, {{100, 0, 2}});
-    histos.add("pT_track_WTS_PID_Pi", "pT with track selection and PID selection of Pi; pT [GeV/c]; Events", kTH1F, {{100, 0, 2}});
+    histos.add("pT_track_WOTS", "pT without track selection; pT [GeV/c]; Events", kTH1F, {{1000, 0, 2}});
+    histos.add("pT_track_WTS", "pT with track selection; pT [GeV/c]; Events", kTH1F, {{1000, 0, 2}});
+    histos.add("pT_track_WTS_PID_Pi", "pT with track selection and PID selection of Pi; pT [GeV/c]; Events", kTH1F, {{1000, 0, 2}});
 
     // Zero charge Event Transverse Momentum
-    histos.add("pT_event_0charge_WTS_PID_Pi", "Event pT in 0 Charge Events With Track Selection and PID Selection of Pi; pT [GeV/c]; Counts", kTH1F, {{100, 0, 2}});
+    histos.add("pT_event_0charge_WTS_PID_Pi", "Event pT in 0 Charge Events With Track Selection and PID Selection of Pi; pT [GeV/c]; Counts", kTH1F, {{1000, 0, 2}});
 
     // Non Zero charge Event Transverse Momentum
     histos.add("pT_event_non0charge_WTS_PID_Pi", "Event pT in Non 0 Charge Events With Track Selection and PID Selection of Pi; pT [GeV/c]; Counts", kTH1F, {{100, 0, 2}});
 
     // Rapidity of 0 charge Events
-    histos.add("rapidity_event_0charge_WTS_PID_Pi", "Rapidity of Events With Track Selection and PID Selection of Pi; y; Counts", kTH1F, {{100, -2.5, 2.5}});
+    histos.add("rapidity_event_0charge_WTS_PID_Pi_domainA", "Rapidity of Events With Track Selection and PID Selection of Pi for p_{T} < 0.15 GeV/c; y; Counts", kTH1F, {{1000, -2.5, 2.5}});
+    histos.add("rapidity_event_0charge_WTS_PID_Pi_domainB", "Rapidity of Events With Track Selection and PID Selection of Pi for 0.15< p_{T} < 0.80 GeV/c; y; Counts", kTH1F, {{1000, -2.5, 2.5}});
+    histos.add("rapidity_event_0charge_WTS_PID_Pi_domainC", "Rapidity of Events With Track Selection and PID Selection of Pi for p_{T} > 0.80 GeV/c; y; Counts", kTH1F, {{1000, -2.5, 2.5}});
 
     // Rapidity of non 0 charge Events
-    histos.add("rapidity_event_non0charge_WTS_PID_Pi", "Rapidity of Events With Track Selection and PID Selection of Pi; y; Counts", kTH1F, {{100, -2.5, 2.5}});
+    histos.add("rapidity_event_non0charge_WTS_PID_Pi_domainA", "Rapidity of Events With Track Selection and PID Selection of Pi for p_{T} < 0.15 GeV/c; y; Counts", kTH1F, {{1000, -2.5, 2.5}});
+    histos.add("rapidity_event_non0charge_WTS_PID_Pi_domainB", "Rapidity of Events With Track Selection and PID Selection of Pi for 0.15< p_{T} < 0.80 GeV/c$; y; Counts", kTH1F, {{1000, -2.5, 2.5}});
+    histos.add("rapidity_event_non0charge_WTS_PID_Pi_domainC", "Rapidity of Events With Track Selection and PID Selection of Pi for p_{T} > 0.80 GeV/c; y; Counts", kTH1F, {{1000, -2.5, 2.5}});
 
     // Invariant Mass of 0 charge events
-    histos.add("invMass_event_0charge_WTS_PID_Pi", "Invariant Mass Distribution of 0 charge Events with PID Selection of Pi; m(#pi^{+}#pi^{-}#pi^{+}#pi^{-}) [GeV/c]", kTH1F, {{1000, 0.8, 2.5}});
+    histos.add("invMass_event_0charge_WTS_PID_Pi_domainA", "Invariant Mass Distribution of 0 charge Events with PID Selection of Pi for p_{T} < 0.15 GeV/c; m(#pi^{+}#pi^{-}#pi^{+}#pi^{-}) [GeV/c]", kTH1F, {{1000, 0.8, 2.5}});       // pT < 0.15GeV
+    histos.add("invMass_event_0charge_WTS_PID_Pi_domainB", "Invariant Mass Distribution of 0 charge Events with PID Selection of Pi for 0.15< p_{T} < 0.80 GeV/c; m(#pi^{+}#pi^{-}#pi^{+}#pi^{-}) [GeV/c]", kTH1F, {{1000, 0.8, 2.5}}); // 0.15GeV < pT < 0.8GeV
+    histos.add("invMass_event_0charge_WTS_PID_Pi_domainC", "Invariant Mass Distribution of 0 charge Events with PID Selection of Pi for p_{T} > 0.80 GeV/c; m(#pi^{+}#pi^{-}#pi^{+}#pi^{-}) [GeV/c]", kTH1F, {{1000, 0.8, 2.5}});       // 0.8GeV < pT
 
     // Invariant mass of non 0 charge events
-    histos.add("invMass_event_non0charge_WTS_PID_Pi", "Invariant Mass Distribution of non 0 charge Events with PID Selection of Pi; m(#pi^{+}#Pi^{-}#pi^{+}#pi^{-}) [GeV/c]", kTH1F, {{1000, 0.8, 2.5}});
+    histos.add("invMass_event_non0charge_WTS_PID_Pi_domainA", "Invariant Mass Distribution of non 0 charge Events with PID Selection of Pi for p_{T} < 0.15 GeV/c; m(#pi^{+}#pi^{-}#pi^{+}#pi^{-}) [GeV/c]", kTH1F, {{1000, 0.8, 2.5}});       // pT < 0.15GeV
+    histos.add("invMass_event_non0charge_WTS_PID_Pi_domainB", "Invariant Mass Distribution of non 0 charge Events with PID Selection of Pi for 0.15< p_{T} < 0.80 GeV/c; m(#pi^{+}#pi^{-}#pi^{+}#pi^{-}) [GeV/c]", kTH1F, {{1000, 0.8, 2.5}}); // 0.15GeV < pT < 0.8GeV
+    histos.add("invMass_event_non0charge_WTS_PID_Pi_domainC", "Invariant Mass Distribution of non 0 charge Events with PID Selection of Pi for p_{T} > 0.80 GeV/c; m(#pi^{+}#pi^{-}#pi^{+}#pi^{-}) [GeV/c]", kTH1F, {{1000, 0.8, 2.5}});       // 0.8GeV < pT
 
     // tpc signal
     histos.add("tpcSignal", "TPC dEdx vs p; p [GeV/c]; dEdx [a.u.]", kTH2F, {{500, 0, 10}, {5000, 0.0, 5000.0}});
@@ -120,8 +128,10 @@ struct UPCAnalysis {
     histos.add("V0A", "V0A amplitude", kTH1F, {{1000, 0.0, 100}});
 
     // Collin Soper Theta and Phi
-    histos.add("CS_phi", "#phi Distribution; #phi; Entries", kTH1F, {{200, -3.2, 3.2}});
-    histos.add("CS_costheta", "#theta Distribution;cos(#theta); Entries", kTH1F, {{200, -1, 1}});
+    histos.add("CS_phi_pair_1", "#phi Distribution; #phi; Entries", kTH1F, {{200, -3.2, 3.2}});
+    histos.add("CS_phi_pair_2", "#phi Distribution; #phi; Entries", kTH1F, {{200, -3.2, 3.2}});
+    histos.add("CS_costheta_pair_1", "#theta Distribution;cos(#theta); Entries", kTH1F, {{200, -1, 1}});
+    histos.add("CS_costheta_pair_2", "#theta Distribution;cos(#theta); Entries", kTH1F, {{200, -1, 1}});
 
   } // End of init function
   //----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
@@ -284,6 +294,7 @@ struct UPCAnalysis {
       return;
     }
 
+    // Selecting Events with net charge = 0
     if (len_Pi_minus == 2 && len_Pi_plus == 2) {
 
       TLorentzVector p1, p2, p3, p4, p1234;
@@ -307,21 +318,35 @@ struct UPCAnalysis {
       k23 = k2 + k3;
       k24 = k2 + k4;
 
-      auto phi_pair_1 = PhiCollinsSoperFrame(k13, k24, k1234);
-      auto phi_pair_2 = PhiCollinsSoperFrame(k14, k23, k1234);
-      auto cos_theta_1 = CosThetaCollinsSoperFrame(k13, k24, k1234);
-      auto cos_theta_2 = CosThetaCollinsSoperFrame(k14, k23, k1234);
-
-      histos.fill(HIST("pT_event_0charge_WTS_PID_Pi"), p1234.Pt());
-      histos.fill(HIST("rapidity_event_0charge_WTS_PID_Pi"), p1234.Rapidity());
-      histos.fill(HIST("invMass_event_0charge_WTS_PID_Pi"), p1234.M());
-      histos.fill(HIST("CS_phi"), phi_pair_1);
-      histos.fill(HIST("CS_phi"), phi_pair_2);
-      histos.fill(HIST("CS_costheta"), cos_theta_1);
-      histos.fill(HIST("CS_costheta"), cos_theta_2);
+      if (fabs(p1234.Rapidity()) < 0.5) {
+        histos.fill(HIST("pT_event_0charge_WTS_PID_Pi"), p1234.Pt());
+        if (p1234.Pt() < 0.15) {
+          histos.fill(HIST("rapidity_event_0charge_WTS_PID_Pi_domainA"), p1234.Rapidity());
+          histos.fill(HIST("invMass_event_0charge_WTS_PID_Pi_domainA"), p1234.M());
+
+          auto phi_pair_1 = PhiCollinsSoperFrame(k13, k24, k1234);
+          auto phi_pair_2 = PhiCollinsSoperFrame(k14, k23, k1234);
+          auto cos_theta_1 = CosThetaCollinsSoperFrame(k13, k24, k1234);
+          auto cos_theta_2 = CosThetaCollinsSoperFrame(k14, k23, k1234);
+
+          histos.fill(HIST("CS_phi_pair_1"), phi_pair_1);
+          histos.fill(HIST("CS_phi_pair_2"), phi_pair_2);
+          histos.fill(HIST("CS_costheta_pair_1"), cos_theta_1);
+          histos.fill(HIST("CS_costheta_pair_2"), cos_theta_2);
+        }
+        if (p1234.Pt() > 0.15 && p1234.Pt() < 0.80) {
+          histos.fill(HIST("rapidity_event_0charge_WTS_PID_Pi_domainB"), p1234.Rapidity());
+          histos.fill(HIST("invMass_event_0charge_WTS_PID_Pi_domainB"), p1234.M());
+        }
+        if (p1234.Pt() > 0.80) {
+          histos.fill(HIST("rapidity_event_0charge_WTS_PID_Pi_domainC"), p1234.Rapidity());
+          histos.fill(HIST("invMass_event_0charge_WTS_PID_Pi_domainC"), p1234.M());
+        }
+      } // End of Rapidity range selection
 
     } // End of Analysis for 0 charge events
 
+    // Selecting Events with net charge != 0 for estimation of background
     if (len_Pi_minus != 2 && len_Pi_plus != 2) {
 
       TLorentzVector p1, p2, p3, p4, p1234;
@@ -332,9 +357,22 @@ struct UPCAnalysis {
 
       p1234 = p1 + p2 + p3 + p4;
 
-      histos.fill(HIST("pT_event_non0charge_WTS_PID_Pi"), p1234.Pt());
-      histos.fill(HIST("rapidity_event_non0charge_WTS_PID_Pi"), p1234.Rapidity());
-      histos.fill(HIST("invMass_event_non0charge_WTS_PID_Pi"), p1234.M());
+      if (fabs(p1234.Rapidity()) < 0.5) {
+        histos.fill(HIST("pT_event_non0charge_WTS_PID_Pi"), p1234.Pt());
+
+        if (p1234.Pt() < 0.15) {
+          histos.fill(HIST("rapidity_event_non0charge_WTS_PID_Pi_domainA"), p1234.Rapidity());
+          histos.fill(HIST("invMass_event_non0charge_WTS_PID_Pi_domainA"), p1234.M());
+        }
+        if (p1234.Pt() > 0.15 && p1234.Pt() < 0.80) {
+          histos.fill(HIST("rapidity_event_non0charge_WTS_PID_Pi_domainB"), p1234.Rapidity());
+          histos.fill(HIST("invMass_event_non0charge_WTS_PID_Pi_domainB"), p1234.M());
+        }
+        if (p1234.Pt() > 0.80) {
+          histos.fill(HIST("rapidity_event_non0charge_WTS_PID_Pi_domainC"), p1234.Rapidity());
+          histos.fill(HIST("invMass_event_non0charge_WTS_PID_Pi_domainC"), p1234.M());
+        }
+      } // End of Rapidity range selection
 
     } // End of Analysis for non 0 charge events