[PWGCF] Add Omega mesons to femto framework

PWGCF/Femto/Core/dataTypes.h

@@ -50,6 +50,9 @@ using TwoTrackResonanceType = uint16_t;
 // datatype for resonances built from two photons (pi0, eta, ...)
 using TwoPhotonResonanceType = uint16_t;
 
+// datatype for resonances built from two tracks and a two-photon resonance (e.g. omega(782) -> pi+ pi- pi0)
+using TrackTrackTwoPhotonResonanceType = uint8_t;
+
 // datatypes for cascades
 using CascadeMaskType = uint32_t;
 using CascadeMaskType001 = uint16_t; // old data type, was too narrow

PWGCF/Femto/Core/modes.h

@@ -241,6 +241,12 @@ enum class TwoPhotonResonance : o2::analysis::femto::datatypes::TwoPhotonResonan
   kEta
 };
 
+// resonances reconstructed from two tracks and a two-photon resonance, e.g. omega(782) -> pi+ pi- pi0.
+// Named kOmegaMeson (not kOmega) to not collide with Cascade::kOmega, the Omega- baryon.
+enum class TrackTrackTwoPhotonResonance : o2::analysis::femto::datatypes::TrackTrackTwoPhotonResonanceType {
+  kOmegaMeson
+};
+
 enum class CharmHadron : o2::analysis::femto::datatypes::CharmHadronType {
   kD0,
   kD0Bar,

PWGCF/Femto/Core/partitions.h

@@ -95,19 +95,42 @@
            ncheckbit(o2::aod::femtotwotrackresonances::maskNegDau, (selection).negDauMaskBelowThres))
 
 // partition for resonances built from two photons (pi0, eta, ...): unlike MAKE_RESONANCE_0/1_PARTITON
-// there is no sign and no momentum-threshold PID switch, just a plain mask check per (unordered) daughter
-// NOLINTNEXTLINE(cppcoreguidelines-macro-usage)
-#define MAKE_TWOPHOTONRESONANCE_PARTITION(selection)                                \
-  (o2::aod::femtobase::stored::pt > (selection).ptMin) &&                           \
-    (o2::aod::femtobase::stored::pt < (selection).ptMax) &&                         \
-    (o2::aod::femtobase::stored::eta > (selection).etaMin) &&                       \
-    (o2::aod::femtobase::stored::eta < (selection).etaMax) &&                       \
-    (o2::aod::femtobase::stored::phi > (selection).phiMin) &&                       \
-    (o2::aod::femtobase::stored::phi < (selection).phiMax) &&                       \
-    (o2::aod::femtobase::stored::mass > (selection).massMin) &&                     \
-    (o2::aod::femtobase::stored::mass < (selection).massMax) &&                     \
-    ncheckbit(o2::aod::femtotwophotonresonances::maskDau1, (selection).dau1Mask) && \
-    ncheckbit(o2::aod::femtotwophotonresonances::maskDau2, (selection).dau2Mask)
+// there is no sign and no momentum-threshold PID switch, and just a single mask check -- both
+// daughters are plain photons with the same selection requirement, so the candidate only stores the
+// AND of both legs' own masks (see femtotwophotonresonances::MaskDau)
+// NOLINTNEXTLINE(cppcoreguidelines-macro-usage)
+#define MAKE_TWOPHOTONRESONANCE_PARTITION(selection)            \
+  (o2::aod::femtobase::stored::pt > (selection).ptMin) &&       \
+    (o2::aod::femtobase::stored::pt < (selection).ptMax) &&     \
+    (o2::aod::femtobase::stored::eta > (selection).etaMin) &&   \
+    (o2::aod::femtobase::stored::eta < (selection).etaMax) &&   \
+    (o2::aod::femtobase::stored::phi > (selection).phiMin) &&   \
+    (o2::aod::femtobase::stored::phi < (selection).phiMax) &&   \
+    (o2::aod::femtobase::stored::mass > (selection).massMin) && \
+    (o2::aod::femtobase::stored::mass < (selection).massMax) && \
+    ncheckbit(o2::aod::femtotwophotonresonances::maskDau, (selection).dauMask)
+
+// partition for resonances built from two tracks and a two-photon resonance (e.g. omega(782) ->
+// pi+ pi- pi0): same pattern as MAKE_RESONANCE_1_PARTITON (daughter masks copied onto the candidate
+// at build time, systematics reselected here), just with 3 daughter masks instead of 2 -- the two
+// charged daughters keep their momentum-threshold PID switch, the neutral daughter does not
+// NOLINTNEXTLINE(cppcoreguidelines-macro-usage)
+#define MAKE_TRACKTRACKTWOPHOTONRESONANCE_PARTITION(selection)                                                  \
+  (o2::aod::femtobase::stored::pt > (selection).ptMin) &&                                                       \
+    (o2::aod::femtobase::stored::pt < (selection).ptMax) &&                                                     \
+    (o2::aod::femtobase::stored::eta > (selection).etaMin) &&                                                   \
+    (o2::aod::femtobase::stored::eta < (selection).etaMax) &&                                                   \
+    (o2::aod::femtobase::stored::phi > (selection).phiMin) &&                                                   \
+    (o2::aod::femtobase::stored::phi < (selection).phiMax) &&                                                   \
+    (o2::aod::femtobase::stored::mass > (selection).massMin) &&                                                 \
+    (o2::aod::femtobase::stored::mass < (selection).massMax) &&                                                 \
+    ifnode(o2::aod::femtotrackstwophotonresonances::posDauHasHighMomentum,                                      \
+           ncheckbit(o2::aod::femtotrackstwophotonresonances::maskPosDau, (selection).posDauMaskAboveThres),    \
+           ncheckbit(o2::aod::femtotrackstwophotonresonances::maskPosDau, (selection).posDauMaskBelowThres)) && \
+    ifnode(o2::aod::femtotrackstwophotonresonances::negDauHasHighMomentum,                                      \
+           ncheckbit(o2::aod::femtotrackstwophotonresonances::maskNegDau, (selection).negDauMaskAboveThres),    \
+           ncheckbit(o2::aod::femtotrackstwophotonresonances::maskNegDau, (selection).negDauMaskBelowThres)) && \
+    ncheckbit(o2::aod::femtotrackstwophotonresonances::maskNeutralDau, (selection).neutralDauMask)
 
 // partition for lambdas
 // NOLINTNEXTLINE(cppcoreguidelines-macro-usage)

PWGCF/Femto/Core/trackTrackTwoPhotonResonanceBuilder.h

@@ -0,0 +1,236 @@
+// 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.
+
+/// \file trackTrackTwoPhotonResonanceBuilder.h
+/// \brief builder for resonances reconstructed from two tracks and a two-photon resonance
+///        (e.g. omega(782) -> pi+ pi- pi0)
+/// \author Anton Riedel, TU München, anton.riedel@tum.de
+
+#ifndef PWGCF_FEMTO_CORE_TRACKTRACKTWOPHOTONRESONANCEBUILDER_H_
+#define PWGCF_FEMTO_CORE_TRACKTRACKTWOPHOTONRESONANCEBUILDER_H_
+
+#include "PWGCF/Femto/Core/dataTypes.h"
+#include "PWGCF/Femto/Core/femtoUtils.h"
+#include "PWGCF/Femto/Core/modes.h"
+#include "PWGCF/Femto/DataModel/FemtoTables.h"
+
+#include "Common/Core/RecoDecay.h"
+
+#include <CommonConstants/MathConstants.h>
+#include <CommonConstants/PhysicsConstants.h>
+#include <Framework/ASoAHelpers.h>
+#include <Framework/AnalysisHelpers.h>
+#include <Framework/Configurable.h>
+#include <Framework/Logger.h>
+
+#include <Math/Vector4D.h> // IWYU pragma: keep (do not replace with Math/Vector4Dfwd.h)
+#include <Math/Vector4Dfwd.h>
+
+#include <string>
+
+namespace o2::analysis::femto::trackstwophotonresonancebuilder
+{
+// filters applied in the producer task (loose pre-selection, applied before the mass window itself)
+struct ConfOmegaMesonFilters : o2::framework::ConfigurableGroup {
+  std::string prefix = std::string("OmegaMesonFilters");
+  o2::framework::Configurable<float> ptMin{"ptMin", 0.f, "Minimum pT"};
+  o2::framework::Configurable<float> ptMax{"ptMax", 10.f, "Maximum pT"};
+  o2::framework::Configurable<float> etaMin{"etaMin", -0.9f, "Minimum eta"};
+  o2::framework::Configurable<float> etaMax{"etaMax", 0.9f, "Maximum eta"};
+  o2::framework::Configurable<float> phiMin{"phiMin", 0.f, "Minimum phi"};
+  o2::framework::Configurable<float> phiMax{"phiMax", 1.f * o2::constants::math::TwoPI, "Maximum phi"};
+  o2::framework::Configurable<float> massMin{"massMin", 0.6f, "Minimum invariant mass"};
+  o2::framework::Configurable<float> massMax{"massMax", 0.95f, "Maximum invariant mass"};
+};
+
+// selection used downstream (QA/pairing) to re-select already produced resonances by mass window
+// and daughter mask -- same pattern as the two-track resonances (TWOTRACKRESONANCE_DEFAULT_SELECTION),
+// just with a 3rd mask for the neutral daughter (no momentum-threshold split there, same as
+// femtotwophotonresonances' single dauMask)
+template <auto& Prefix>
+struct ConfOmegaMesonSelection : o2::framework::ConfigurableGroup {
+  std::string prefix = Prefix;
+  o2::framework::Configurable<int> pdgCodeAbs{"pdgCodeAbs", o2::constants::physics::Pdg::kOmega, "Absolute PDG code of the resonance (pdg[omega(782)]=223)"};
+  o2::framework::Configurable<float> ptMin{"ptMin", 0.f, "Minimum pT"};
+  o2::framework::Configurable<float> ptMax{"ptMax", 10.f, "Maximum pT"};
+  o2::framework::Configurable<float> etaMin{"etaMin", -0.9f, "Minimum eta"};
+  o2::framework::Configurable<float> etaMax{"etaMax", 0.9f, "Maximum eta"};
+  o2::framework::Configurable<float> phiMin{"phiMin", 0.f, "Minimum phi"};
+  o2::framework::Configurable<float> phiMax{"phiMax", 1.f * o2::constants::math::TwoPI, "Maximum phi"};
+  o2::framework::Configurable<float> massMin{"massMin", 0.6f, "Minimum invariant mass"};
+  o2::framework::Configurable<float> massMax{"massMax", 0.95f, "Maximum invariant mass"};
+  o2::framework::Configurable<o2::analysis::femto::datatypes::TrackMaskType> posDauMaskBelowThres{"posDauMaskBelowThres", 0x10u, "Bitmask for positive daughter below threshold"};
+  o2::framework::Configurable<o2::analysis::femto::datatypes::TrackMaskType> posDauMaskAboveThres{"posDauMaskAboveThres", 0x8u, "Bitmask for positive daughter above threshold"};
+  o2::framework::Configurable<o2::analysis::femto::datatypes::TrackMaskType> negDauMaskBelowThres{"negDauMaskBelowThres", 0x2u, "Bitmask for negative daughter below threshold"};
+  o2::framework::Configurable<o2::analysis::femto::datatypes::TrackMaskType> negDauMaskAboveThres{"negDauMaskAboveThres", 0x1u, "Bitmask for negative daughter above threshold"};
+  o2::framework::Configurable<o2::analysis::femto::datatypes::PhotonMaskType> neutralDauMask{"neutralDauMask", 0, "Bitmask required for the neutral (two-photon-resonance) daughter"};
+};
+
+constexpr const char PrefixOmegaMesonSelection1[] = "OmegaMesonSelection1";
+using ConfOmegaMesonSelection1 = ConfOmegaMesonSelection<PrefixOmegaMesonSelection1>;
+
+struct TrackTrackTwoPhotonResonanceBuilderProducts : o2::framework::ProducesGroup {
+  o2::framework::Produces<o2::aod::FOmegaMesons> producedOmegaMesons;
+  o2::framework::Produces<o2::aod::FOmegaMesonMasks> producedOmegaMesonMasks;
+};
+
+struct ConfTrackTrackTwoPhotonResonanceTables : o2::framework::ConfigurableGroup {
+  std::string prefix = std::string("TrackTrackTwoPhotonResonanceTables");
+  o2::framework::Configurable<int> produceOmegaMesons{"produceOmegaMesons", -1, "Produce OmegaMesons (-1: auto; 0 off; 1 on)"};
+  o2::framework::Configurable<int> produceOmegaMesonMasks{"produceOmegaMesonMasks", -1, "Produce OmegaMesonMasks (-1: auto; 0 off; 1 on)"};
+};
+
+/// \brief Builder for resonances reconstructed from two tracks and a two-photon resonance
+/// (e.g. omega(782) -> pi+ pi- pi0).
+///
+/// posDau/negDau are drawn from already-selected FTracks partitions (sign and PID handled by the
+/// normal track selection, same as any other track daughter use case), and neutralDau from an
+/// already-built FPi0s/FEtas partition. This builder does the 3-body combinatorics, the
+/// resonance's own mass window, and -- like TwoTrackResonanceBuilder -- copies the daughters'
+/// bitmasks onto the candidate so systematic variations can be reselected downstream from the
+/// candidate table alone, without rejoining the daughter tables.
+template <modes::TrackTrackTwoPhotonResonance resoType>
+class TrackTrackTwoPhotonResonanceBuilder
+{
+ public:
+  TrackTrackTwoPhotonResonanceBuilder() = default;
+  ~TrackTrackTwoPhotonResonanceBuilder() = default;
+
+  template <typename T1, typename T2, typename T3, typename T4, typename T5>
+  void init(T1& confFilter, T2& confPosDauSelection, T3& confNegDauSelection, T4& confTable, T5& initContext)
+  {
+    mMassMin = confFilter.massMin.value;
+    mMassMax = confFilter.massMax.value;
+    mPtMin = confFilter.ptMin.value;
+    mPtMax = confFilter.ptMax.value;
+    mEtaMin = confFilter.etaMin.value;
+    mEtaMax = confFilter.etaMax.value;
+    mPhiMin = confFilter.phiMin.value;
+    mPhiMax = confFilter.phiMax.value;
+
+    mPosDauThreshold = confPosDauSelection.pidThres.value;
+    mNegDauThreshold = confNegDauSelection.pidThres.value;
+
+    if constexpr (modes::isEqual(resoType, modes::TrackTrackTwoPhotonResonance::kOmegaMeson)) {
+      LOG(info) << "Initialize femto OmegaMeson builder...";
+      mPosDauMass = o2::constants::physics::MassPiPlus;
+      mNegDauMass = o2::constants::physics::MassPiMinus;
+      mProduceOmegaMesons = utils::enableTable("FOmegaMesons_001", confTable.produceOmegaMesons.value, initContext);
+      mProduceOmegaMesonMasks = utils::enableTable("FOmegaMesonMasks_001", confTable.produceOmegaMesonMasks.value, initContext);
+    }
+
+    if (mProduceOmegaMesons || mProduceOmegaMesonMasks) {
+      mFillAnyTable = true;
+    } else {
+      LOG(info) << "No tables configured, Selection object will not be configured...";
+      LOG(info) << "Initialization done...";
+      return;
+    }
+    LOG(info) << "Initialization done...";
+  }
+
+  template <typename T1, typename T2, typename T3, typename T4, typename T5, typename T6>
+  void fillResonances(T1 const& col, T2& resonanceProducts, T3& posDauPartition, T4& negDauPartition, T5& neutralDauPartition, T6& cache)
+  {
+    if (!mFillAnyTable) {
+      return;
+    }
+    auto posDauSlice = posDauPartition->sliceByCached(o2::aod::femtobase::stored::fColId, col.globalIndex(), cache);
+    auto negDauSlice = negDauPartition->sliceByCached(o2::aod::femtobase::stored::fColId, col.globalIndex(), cache);
+    auto neutralDauSlice = neutralDauPartition->sliceByCached(o2::aod::femtobase::stored::fColId, col.globalIndex(), cache);
+    for (auto const& [posDau, negDau, neutralDau] : o2::soa::combinations(o2::soa::CombinationsFullIndexPolicy(posDauSlice, negDauSlice, neutralDauSlice))) {
+      this->fillResonance(col, posDau, negDau, neutralDau, resonanceProducts);
+    }
+  }
+
+ private:
+  template <typename T1, typename T2, typename T3>
+  void reconstructResonance(T1 const& posDau, T2 const& negDau, T3 const& neutralDau)
+  {
+    ROOT::Math::PtEtaPhiMVector vecPosDau{posDau.pt(), posDau.eta(), posDau.phi(), mPosDauMass};
+    ROOT::Math::PtEtaPhiMVector vecNegDau{negDau.pt(), negDau.eta(), negDau.phi(), mNegDauMass};
+    ROOT::Math::PtEtaPhiMVector vecNeutralDau{neutralDau.pt(), neutralDau.eta(), neutralDau.phi(), neutralDau.mass()};
+    ROOT::Math::PtEtaPhiMVector vecResonance = vecPosDau + vecNegDau + vecNeutralDau;
+
+    mPt = vecResonance.Pt();
+    mEta = vecResonance.Eta();
+    mPhi = RecoDecay::constrainAngle(vecResonance.Phi());
+    mMass = vecResonance.M();
+  }
+
+  [[nodiscard]] bool checkFilters() const
+  {
+    return ((mMass > mMassMin && mMass < mMassMax) &&
+            (mPt > mPtMin && mPt < mPtMax) &&
+            (mEta > mEtaMin && mEta < mEtaMax) &&
+            (mPhi >= mPhiMin && mPhi < mPhiMax));
+  }
+
+  template <typename T1, typename T2, typename T3, typename T4, typename T5>
+  void fillResonance(T1 const& col, T2 const& posDau, T3 const& negDau, T4 const& neutralDau, T5& resonanceProducts)
+  {
+    reconstructResonance(posDau, negDau, neutralDau);
+    if (!checkFilters()) {
+      return;
+    }
+
+    bool posDauHasHighMomentum = posDau.p() > mPosDauThreshold;
+    bool negDauHasHighMomentum = negDau.p() > mNegDauThreshold;
+
+    if constexpr (modes::isEqual(resoType, modes::TrackTrackTwoPhotonResonance::kOmegaMeson)) {
+      if (mProduceOmegaMesons) {
+        resonanceProducts.producedOmegaMesons(col.globalIndex(),
+                                              mPt,
+                                              mEta,
+                                              mPhi,
+                                              mMass,
+                                              posDau.globalIndex(),
+                                              negDau.globalIndex(),
+                                              neutralDau.globalIndex());
+      }
+      if (mProduceOmegaMesonMasks) {
+        resonanceProducts.producedOmegaMesonMasks(posDau.mask(),
+                                                  posDauHasHighMomentum,
+                                                  negDau.mask(),
+                                                  negDauHasHighMomentum,
+                                                  neutralDau.maskDau());
+      }
+    }
+  }
+
+  // cached kinematics of the resonance
+  float mPt = 0.f;
+  float mEta = 0.f;
+  float mPhi = 0.f;
+  float mMass = 0.f;
+
+  float mMassMin = 0.f;
+  float mMassMax = 1.f;
+  float mPtMin = 0.f;
+  float mPtMax = 10.f;
+  float mEtaMin = -0.9f;
+  float mEtaMax = 0.9f;
+  float mPhiMin = 0.f;
+  float mPhiMax = o2::constants::math::TwoPI;
+
+  float mPosDauMass = 0.f;
+  float mNegDauMass = 0.f;
+
+  float mPosDauThreshold = 0.f;
+  float mNegDauThreshold = 0.f;
+
+  bool mFillAnyTable = false;
+  bool mProduceOmegaMesons = false;
+  bool mProduceOmegaMesonMasks = false;
+};
+
+} // namespace o2::analysis::femto::trackstwophotonresonancebuilder
+#endif // PWGCF_FEMTO_CORE_TRACKTRACKTWOPHOTONRESONANCEBUILDER_H_