adding missing file to the previous commit

Author: apalasciano

PWGHF/HFC/DataModel/CorrelationTables.h

@@ -498,19 +498,19 @@ DECLARE_SOA_TABLE(TrkRecInfoDplus, "AOD", "TRKRECINFODPLUS", //! Tracks Reconstr
                   aod::hf_correlation_dplus_hadron::TrackTPCNClsCrossedRows);
 
 // definition of columns and tables for the beauty-mother information of the charm-hadron trigger (MC only), usable by any D-hadron correlation analysis
-namespace hf_correlation_b_mother
+namespace hf_correlation_info_b_mother
 {
 DECLARE_SOA_COLUMN(PtB, ptB, float);                   //! Generated pT of the beauty mother of the charm hadron (-1 if not from beauty)
 DECLARE_SOA_COLUMN(DeltaPhiBtoD, deltaPhiBtoD, float); //! phi(charm hadron) - phi(B mother, generated) in [-pihalf, 3.*pihalf) (-999 if not from beauty)
-} // namespace hf_correlation_b_mother
+} // namespace hf_correlation_info_b_mother
 
 DECLARE_SOA_TABLE(BMotherPairInfo, "AOD", "BMOTHERPAIRINFO", //! Charm-hadron-hadron pairs beauty-mother information, joinable with the pair table
-                  aod::hf_correlation_b_mother::PtB,
-                  aod::hf_correlation_b_mother::DeltaPhiBtoD);
+                  aod::hf_correlation_info_b_mother::PtB,
+                  aod::hf_correlation_info_b_mother::DeltaPhiBtoD);
 
 DECLARE_SOA_TABLE(BMotherCandInfo, "AOD", "BMOTHERCANDINFO", //! Charm-hadron candidates beauty-mother information, joinable with the candidate table
-                  aod::hf_correlation_b_mother::PtB,
-                  aod::hf_correlation_b_mother::DeltaPhiBtoD);
+                  aod::hf_correlation_info_b_mother::PtB,
+                  aod::hf_correlation_info_b_mother::DeltaPhiBtoD);
 
 // definition of columns and tables for Dstar-Hadron correlation pair
 namespace hf_correlation_dstar_hadron

PWGHF/HFC/Utils/utilsCorrelations.h

@@ -18,6 +18,7 @@
 
 #include "PWGHF/Core/DecayChannels.h"
 
+#include "Common/Core/RecoDecay.h"
 #include "Common/DataModel/PIDResponseTOF.h"
 #include "Common/DataModel/PIDResponseTPC.h"
 
@@ -29,6 +30,9 @@
 
 #include <cmath>
 #include <cstddef>
+#include <cstdint>
+#include <utility>
+#include <vector>
 
 namespace o2::analysis::hf_correlations
 {
@@ -227,5 +231,62 @@ int findLeadingParticleMcGen(TMcParticles const& mcParticles, T1 const etaTrackM
   }
   return leadingParticle.globalIndex();
 }
+
+// ======= Beauty-mother information of non-prompt charm hadrons ============
+constexpr float PtBMotherDefault{-1.f};         // pT(B mother) returned when the charm hadron is not from beauty
+constexpr float DeltaPhiBMotherDefault{-999.f}; // phi(charm hadron) - phi(B mother) returned when the charm hadron is not from beauty
+
+/// Gets the generated beauty mother of a reconstructed charm-hadron candidate matched to a non-prompt charm hadron
+/// \tparam TTracks is the track table with MC labels, used to access the candidate prongs
+/// \param candidate is the reconstructed candidate (with originMcRec column)
+/// \param mcParticles is the table of MC particles
+/// \param pdgCharmHadron is the PDG code of the charm hadron (e.g. Pdg::kDPlus), antiparticles are accepted
+/// \param depthMaxDaughters is the max. depth of the candidate prong in the charm-hadron decay chain (> 1 for resonant channels)
+/// \return pair (pT of the B mother, phi(candidate, reco) - phi(B mother, gen) in [-pi, pi)), default values if the candidate is not from beauty
+template <typename TTracks, typename TCandidate, typename TMcParticles>
+std::pair<float, float> getBMotherInfoMcRec(TCandidate const& candidate, TMcParticles const& mcParticles, int pdgCharmHadron, int8_t depthMaxDaughters = 2)
+{
+  std::pair<float, float> bMotherInfo{PtBMotherDefault, DeltaPhiBMotherDefault};
+  if (candidate.originMcRec() != RecoDecay::OriginType::NonPrompt) {
+    return bMotherInfo;
+  }
+  // retrieve the generated charm hadron from the MC particle of one of its daughters
+  auto prong0 = candidate.template prong0_as<TTracks>();
+  if (!prong0.has_mcParticle()) {
+    return bMotherInfo;
+  }
+  auto prong0McPart = prong0.template mcParticle_as<TMcParticles>();
+  int const indexCharmHadronGen = RecoDecay::getMother(mcParticles, prong0McPart, pdgCharmHadron, true, nullptr, depthMaxDaughters);
+  if (indexCharmHadronGen < 0) {
+    return bMotherInfo;
+  }
+  // same procedure used in the candidate creators to fill PtBhadMotherPart
+  auto charmHadronGen = mcParticles.rawIteratorAt(indexCharmHadronGen - mcParticles.offset());
+  std::vector<int> idxBhadMothers{};
+  if (RecoDecay::getCharmHadronOrigin(mcParticles, charmHadronGen, false, &idxBhadMothers) != RecoDecay::OriginType::NonPrompt || idxBhadMothers.empty()) {
+    return bMotherInfo;
+  }
+  auto bHadMother = mcParticles.rawIteratorAt(idxBhadMothers[0] - mcParticles.offset());
+  bMotherInfo.first = bHadMother.pt();
+  bMotherInfo.second = RecoDecay::constrainAngle(candidate.phi() - bHadMother.phi(), -o2::constants::math::PI);
+  return bMotherInfo;
+}
+
+/// Gets the beauty mother of a generated charm hadron
+/// \param particle is the generated charm hadron (with originMcGen and idxBhadMotherPart columns)
+/// \param mcParticles is the table of MC particles containing the B mother
+/// \return pair (pT of the B mother, phi(charm hadron) - phi(B mother) in [-pi, pi)), default values if the charm hadron is not from beauty
+template <typename TParticle, typename TMcParticles>
+std::pair<float, float> getBMotherInfoMcGen(TParticle const& particle, TMcParticles const& mcParticles)
+{
+  std::pair<float, float> bMotherInfo{PtBMotherDefault, DeltaPhiBMotherDefault};
+  if (particle.originMcGen() != RecoDecay::OriginType::NonPrompt || particle.idxBhadMotherPart() < 0) {
+    return bMotherInfo;
+  }
+  auto bHadMother = mcParticles.rawIteratorAt(particle.idxBhadMotherPart() - mcParticles.offset());
+  bMotherInfo.first = bHadMother.pt();
+  bMotherInfo.second = RecoDecay::constrainAngle(particle.phi() - bHadMother.phi(), -o2::constants::math::PI);
+  return bMotherInfo;
+}
 } // namespace o2::analysis::hf_correlations
 #endif // PWGHF_HFC_UTILS_UTILSCORRELATIONS_H_