[PWGJE,Infrastructure] Create qg tree creator

PWGJE/Tasks/CMakeLists.txt

@@ -403,4 +403,13 @@
                         SOURCES bjetCentMult.cxx
                         PUBLIC_LINK_LIBRARIES O2::Framework O2Physics::PWGJECore O2Physics::AnalysisCore
                         COMPONENT_NAME Analysis)
+
+o2physics_add_dpl_workflow(qg-tree-creator
+  SOURCES qgTreeCreator.cxx
+  PUBLIC_LINK_LIBRARIES
+    O2::Framework
+    O2Physics::AnalysisCore
+    O2Physics::PWGJECore
+  COMPONENT_NAME Analysis)
+
 endif()

PWGJE/Tasks/qgTreeCreator.cxx

@@ -0,0 +1,210 @@
+// Copyright 2019-2026 CERN and copyright holders of ALICE O2.
+// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
+// All rights not expressly granted are reserved.
+//
+// This software is distributed under the terms of the GNU General Public
+// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
+//
+// In applying this license CERN does not waive the privileges and immunities
+// granted to it by virtue of its status as an Intergovernmental Organization
+// or submit itself to any jurisdiction.
+
+#include "Framework/runDataProcessing.h"
+#include "Framework/AnalysisTask.h"
+#include "Framework/HistogramRegistry.h"
+#include "Framework/Configurable.h"
+
+#include "PWGJE/DataModel/Jet.h"
+#include "PWGJE/DataModel/JetMatching.h"
+#include "Common/DataModel/TrackSelectionTables.h"
+#include "Common/DataModel/MCTruthContainer.h"
+
+#include <cmath>
+
+using namespace o2;
+using namespace o2::framework;
+
+namespace o2::aod
+{
+DECLARE_SOA_COLUMN(JetPt, jetPt, float);
+DECLARE_SOA_COLUMN(JetEta, jetEta, float);
+DECLARE_SOA_COLUMN(JetPhi, jetPhi, float);
+DECLARE_SOA_COLUMN(NConst, nConst, int);
+DECLARE_SOA_COLUMN(Girth, girth, float);
+DECLARE_SOA_COLUMN(PTD, pTD, float);
+DECLARE_SOA_COLUMN(MatchDeltaR, matchDeltaR, float);
+DECLARE_SOA_COLUMN(PtResponse, ptResponse, float);
+DECLARE_SOA_COLUMN(QGLabel, qgLabel, int);
+
+DECLARE_SOA_TABLE(QGJetTable, "AOD", "QGJET",
+                  JetPt,
+                  JetEta,
+                  JetPhi,
+                  NConst,
+                  Girth,
+                  PTD,
+                  MatchDeltaR,
+                  PtResponse,
+                  QGLabel);
+}
+
+//------------------------------------------------
+// helper functions
+//------------------------------------------------
+float deltaPhi(float phi1, float phi2)
+{
+  return std::remainder(phi1 - phi2, 2.f * static_cast<float>(M_PI));
+}
+
+float deltaR(float eta1, float phi1, float eta2, float phi2)
+{
+  float deta = eta1 - eta2;
+  float dphi = deltaPhi(phi1, phi2);
+  return std::sqrt(deta * deta + dphi * dphi);
+}
+
+//------------------------------------------------
+// find initiating parton by ancestry
+//------------------------------------------------
+int getInitiatingParton(auto const& particle,
+                        aod::McParticles const& mcParticles)
+{
+  auto p = particle;
+  int pdg = p.pdgCode();
+
+  while (p.has_mothers()) {
+    auto mothers = p.mothers_as<aod::McParticles>();
+    if (mothers.size() == 0) {
+      break;
+    }
+
+    auto mom = mothers.iteratorAt(0);
+    int mpdg = mom.pdgCode();
+
+    // stop at quark or gluon
+    if (std::abs(mpdg) == 21 || (std::abs(mpdg) >= 1 && std::abs(mpdg) <= 6)) {
+      pdg = mpdg;
+    }
+
+    p = mom;
+  }
+
+  return pdg;
+}
+
+//------------------------------------------------
+// main task
+//------------------------------------------------
+struct QGTreeCreator {
+
+  Configurable<float> jetPtMin{"jetPtMin",10.f};
+  Configurable<float> maxMatchDeltaR{"maxMatchDeltaR",0.3f};
+
+  Produces<aod::QGJetTable> qgjets;
+
+  void process(aod::ChargedMCDetectorLevelJets const& recoJets,
+               aod::ChargedMCParticleLevelJets const& truthJets,
+               aod::ChargedMCDetectorLevelJetsMatchedToChargedMCParticleLevelJets const& matches,
+               aod::McParticles const& mcParticles)
+  {
+    for (auto const& jet : recoJets) {
+
+      if (jet.pt() < jetPtMin)
+        continue;
+
+      //----------------------------------
+      // compute jet observables
+      //----------------------------------
+      int nconst = 0;
+      float sumPt = 0;
+      float sumPt2 = 0;
+      float sumPtDr = 0;
+
+      for (auto const& c : jet.tracks_as<aod::ChargedMCDetectorLevelJetConstituent>()) {
+        float pt = c.pt();
+        float dr = deltaR(c.eta(), c.phi(), jet.eta(), jet.phi());
+
+        nconst++;
+        sumPt += pt;
+        sumPt2 += pt*pt;
+        sumPtDr += pt*dr;
+      }
+
+      float girth = sumPt>0 ? sumPtDr/sumPt : -1;
+      float ptd   = sumPt>0 ? std::sqrt(sumPt2)/sumPt : -1;
+
+      //----------------------------------
+      // matching block
+      //----------------------------------
+      float matchDr = -1;
+      float ptResp = -1;
+      int qg = -1;
+
+      for (auto const& match : matches) {
+
+        if (match.chargedMCDetectorLevelJetId() != jet.globalIndex())
+          continue;
+
+        auto truthJet = truthJets.iteratorAt(
+            match.chargedMCParticleLevelJetId());
+
+        matchDr = deltaR(jet.eta(), jet.phi(),
+                         truthJet.eta(), truthJet.phi());
+
+        if (matchDr > maxMatchDeltaR)
+          continue;
+
+        ptResp = jet.pt() / truthJet.pt();
+
+        //----------------------------------
+        // find initiating parton
+        //----------------------------------
+        float maxPt = -1;
+        int pdg = 0;
+
+        for (auto const& tc :
+             truthJet.tracks_as<aod::ChargedMCParticleLevelJetConstituent>())
+        {
+          if (!tc.has_mcParticle())
+            continue;
+
+          auto mc = tc.mcParticle();
+
+          if (tc.pt() > maxPt) {
+            maxPt = tc.pt();
+            pdg = getInitiatingParton(mc, mcParticles);
+          }
+        }
+
+        //----------------------------------
+        // assign q/g label
+        //----------------------------------
+        if (std::abs(pdg) == 21)
+          qg = 1; // gluon
+        else if (std::abs(pdg) >= 1 && std::abs(pdg) <= 6)
+          qg = 0; // quark
+
+        break;
+      }
+
+      //----------------------------------
+      // store
+      //----------------------------------
+      qgjets(jet.pt(),
+             jet.eta(),
+             jet.phi(),
+             nconst,
+             girth,
+             ptd,
+             matchDr,
+             ptResp,
+             qg);
+    }
+  }
+};
+
+WorkflowSpec defineDataProcessing(ConfigContext const& cfgc)
+{
+  return WorkflowSpec{
+    adaptAnalysisTask<QGTreeCreator>(cfgc, TaskName{"qg-tree-creator"})};
+}