Feat: add rapidity cut for mother particles

Author: ariedel-cern

PWGCF/Femto/Core/femtoUtils.h

@@ -82,6 +82,15 @@ float itsSignal(T const& track)
   return static_cast<float>(signal);
 };
 
+// Delta(1232) baryons: no kXxx enum entry exists for these in TPDGCode.h (only the raw codes used
+// internally by TDatabasePDG's particle-table construction) and no mass constant exists in
+// PhysicsConstants.h either, so both the codes and the mass are hardcoded here, same as kRho770_0/
+// kRho770Plus below.
+constexpr int kDeltaMinus1232 = 1114;
+constexpr int kDelta01232 = 2114;
+constexpr int kDeltaPlus1232 = 2214;
+constexpr int kDeltaPlusPlus1232 = 2224;
+
 inline double getPdgMass(int pdgCode)
 {
   // use this function instead of TDatabasePDG to return masses defined in the PhysicsConstants.h header
@@ -149,6 +158,12 @@ inline double getPdgMass(int pdgCode)
     case o2::constants::physics::kEta:
       mass = o2::constants::physics::MassEta;
       break;
+    case kDeltaMinus1232:
+    case kDelta01232:
+    case kDeltaPlus1232:
+    case kDeltaPlusPlus1232:
+      mass = 1.232; // not defined in O2?
+      break;
     default:
       LOG(warn) << "PDG code " << pdgCode << " is not suppored. Return 0... ";
   }

PWGCF/Femto/Core/particleCleaner.h

@@ -16,6 +16,10 @@
 #ifndef PWGCF_FEMTO_CORE_PARTICLECLEANER_H_
 #define PWGCF_FEMTO_CORE_PARTICLECLEANER_H_
 
+#include "PWGCF/Femto/Core/femtoUtils.h"
+
+#include "Common/Core/RecoDecay.h"
+
 #include <CommonConstants/MathConstants.h>
 #include <Framework/Configurable.h>
 
@@ -45,6 +49,11 @@ struct ConfParticleCleaner : o2::framework::ConfigurableGroup {
   o2::framework::Configurable<float> motherPtMax{"motherPtMax", 1e6f, "Maximum pT of the mother. One shared window applies regardless of which requiredMotherPdgCodes/rejectMotherPdgCodes entry the mother's own pdg code matched"};
   o2::framework::Configurable<float> motherEtaMin{"motherEtaMin", -1e6f, "Minimum eta of the mother. One shared window applies regardless of which requiredMotherPdgCodes/rejectMotherPdgCodes entry the mother's own pdg code matched"};
   o2::framework::Configurable<float> motherEtaMax{"motherEtaMax", 1e6f, "Maximum eta of the mother. One shared window applies regardless of which requiredMotherPdgCodes/rejectMotherPdgCodes entry the mother's own pdg code matched"};
+  // Rapidity cut on the mother. FMcMothers has no mass column, so the mass is looked up from
+  // PdgCode via utils::getPdgMass() (the same lookup pairHistManager.h uses for kstar/Q3) and
+  // combined with the mother's pt/eta to get y -- see RecoDecay::y(pt, eta, m).
+  o2::framework::Configurable<float> motherRapidityMin{"motherRapidityMin", -1e6f, "Minimum rapidity of the mother. One shared window applies regardless of which requiredMotherPdgCodes/rejectMotherPdgCodes entry the mother's own pdg code matched"};
+  o2::framework::Configurable<float> motherRapidityMax{"motherRapidityMax", 1e6f, "Maximum rapidity of the mother. One shared window applies regardless of which requiredMotherPdgCodes/rejectMotherPdgCodes entry the mother's own pdg code matched"};
   o2::framework::Configurable<float> motherPhiMin{"motherPhiMin", 0.f, "Minimum phi of the mother. One shared window applies regardless of which requiredMotherPdgCodes/rejectMotherPdgCodes entry the mother's own pdg code matched"};
   o2::framework::Configurable<float> motherPhiMax{"motherPhiMax", 1.f * o2::constants::math::TwoPI, "Maximum phi of the mother. One shared window applies regardless of which requiredMotherPdgCodes/rejectMotherPdgCodes entry the mother's own pdg code matched -- not one window per pdg code."};
   o2::framework::Configurable<std::vector<int>> requiredPartonicMotherPdgCodes{"requiredPartonicMotherPdgCodes", {}, "Only consider particles whose partonic mothers have one of the supplied pdg codes (including the sign!)"};
@@ -135,6 +144,8 @@ class ParticleCleaner
     mMotherEtaMax = confMpc.motherEtaMax.value;
     mMotherPhiMin = confMpc.motherPhiMin.value;
     mMotherPhiMax = confMpc.motherPhiMax.value;
+    mMotherRapidityMin = confMpc.motherRapidityMin.value;
+    mMotherRapidityMax = confMpc.motherRapidityMax.value;
 
     mRequiredPartonicMotherPdgCodes = confMpc.requiredPartonicMotherPdgCodes.value;
     mRejectedPartonicMotherPdgCodes = confMpc.rejectPartonicMotherPdgCodes.value;
@@ -231,14 +242,23 @@ class ParticleCleaner
         }
       }
 
-      // One shared pt/eta/phi window, applied to the mother regardless of which (if any)
+      // One shared pt/eta/phi/rapidity window, applied to the mother regardless of which (if any)
       // requiredMotherPdgCodes/rejectMotherPdgCodes entry it matched above -- see the comment on
       // ConfParticleCleaner's motherPtMin et al.
       if (!(mother.pt() > mMotherPtMin && mother.pt() < mMotherPtMax &&
             mother.eta() > mMotherEtaMin && mother.eta() < mMotherEtaMax &&
             mother.phi() > mMotherPhiMin && mother.phi() < mMotherPhiMax)) {
         motherKinematicsOk = false;
       }
+
+      // rapidity needs the mother's mass, which FMcMothers does not store directly -- look it up
+      // from its pdg code (same mechanism as the kstar/Q3 mass lookup in pairHistManager.h)
+      if (mMotherRapidityMin > -1e6f || mMotherRapidityMax < 1e6f) {
+        double motherRapidity = RecoDecay::y(mother.pt(), mother.eta(), utils::getPdgMass(mother.pdgCode()));
+        if (!(motherRapidity > mMotherRapidityMin && motherRapidity < mMotherRapidityMax)) {
+          motherKinematicsOk = false;
+        }
+      }
     }
 
     // MC partonic mother — same idea, via mcParticle
@@ -291,6 +311,8 @@ class ParticleCleaner
   float mMotherEtaMax = 1e6f;
   float mMotherPhiMin = 0.f;
   float mMotherPhiMax = 1.f * o2::constants::math::TwoPI;
+  float mMotherRapidityMin = -1e6f;
+  float mMotherRapidityMax = 1e6f;
   std::vector<int> mRequiredPartonicMotherPdgCodes;
   std::vector<int> mRejectedPartonicMotherPdgCodes;
 };