PWGHF: Added parametrized pT differential cut in Dplus candidate selector (#7333)

* Added parametrized invariant mass cut to Dplus candidate selector to analyse triggered data

* Please consider the following formatting changes

* Update utilsAnalysis.h

* Please consider the following formatting changes

---------

Co-authored-by: ALICE Action Bot <alibuild@cern.ch>

Author: Luca610

PWGHF/TableProducer/candidateSelectorDplusToPiKPi.cxx

@@ -25,6 +25,7 @@
 #include "PWGHF/Core/HfMlResponseDplusToPiKPi.h"
 #include "PWGHF/DataModel/CandidateReconstructionTables.h"
 #include "PWGHF/DataModel/CandidateSelectionTables.h"
+#include "PWGHF/Utils/utilsAnalysis.h"
 
 using namespace o2;
 using namespace o2::analysis;
@@ -72,6 +73,8 @@ struct HfCandidateSelectorDplusToPiKPi {
   Configurable<std::vector<std::string>> onnxFileNames{"onnxFileNames", std::vector<std::string>{"ModelHandler_onnx_DPlusToKPiPi.onnx"}, "ONNX file names for each pT bin (if not from CCDB full path)"};
   Configurable<int64_t> timestampCCDB{"timestampCCDB", -1, "timestamp of the ONNX file for ML model used to query in CCDB"};
   Configurable<bool> loadModelsFromCCDB{"loadModelsFromCCDB", false, "Flag to enable or disable the loading of models from CCDB"};
+  // Mass Cut for trigger analysis
+  Configurable<bool> useTriggerMassCut{"useTriggerMassCut", false, "Flag to enable parametrize pT differential mass cut for triggered data"};
 
   o2::analysis::HfMlResponseDplusToPiKPi<float> hfMlResponse;
   std::vector<float> outputMlNotPreselected = {};
@@ -80,6 +83,7 @@ struct HfCandidateSelectorDplusToPiKPi {
   TrackSelectorPi selectorPion;
   TrackSelectorKa selectorKaon;
   HfHelper hfHelper;
+  o2::analysis::HfTriggerCuts hfTriggerCuts;
 
   using TracksSel = soa::Join<aod::TracksWExtra, aod::TracksPidPi, aod::PidTpcTofFullPi, aod::TracksPidKa, aod::PidTpcTofFullKa>;
 
@@ -149,6 +153,9 @@ struct HfCandidateSelectorDplusToPiKPi {
     if (std::abs(hfHelper.invMassDplusToPiKPi(candidate) - o2::constants::physics::MassDPlus) > cuts->get(pTBin, "deltaM")) {
       return false;
     }
+    if (useTriggerMassCut && !hfTriggerCuts.isSelectedDplusInMassRange(hfHelper.invMassDplusToPiKPi(candidate), candpT)) {
+      return false;
+    }
     if (candidate.decayLength() < cuts->get(pTBin, "decay length")) {
       return false;
     }

PWGHF/Utils/utilsAnalysis.h

@@ -17,6 +17,9 @@
 
 #include <algorithm> // std::upper_bound
 #include <iterator>  // std::distance
+#include <string>    //std::string
+#include "Common/Core/RecoDecay.h"
+#include "CommonConstants/PhysicsConstants.h"
 
 namespace o2::analysis
 {
@@ -108,6 +111,34 @@ bool isSelectedTrackTpcQuality(T const& track, const int tpcNClustersFoundMin, c
   return true;
 }
 
+struct HfTriggerCuts : o2::framework::ConfigurableGroup {
+  std::string prefix = "hfMassCut"; // JSON group name
+
+  static constexpr float defaultDeltaMassPars3Prong[1][2] = {{-0.0025f, 0.0001f}};
+  static constexpr float defaultSigmaPars3Prong[1][2] = {{0.00796f, 0.00176f}};
+  o2::framework::Configurable<float> nSigma{"nSigma", 2.5, "Number of Sigmas for pT differential mass cut"};
+  o2::framework::Configurable<float> pTMaxDeltaMass{"pTMaxDeltaMass", 10., "Max pT to apply delta mass shift to PDG mass value"};
+  o2::framework::Configurable<float> pTMaxMassCut{"pTMaxMassCut", 8., "Max pT to apply pT differential cut"};
+  o2::framework::Configurable<o2::framework::LabeledArray<float>> deltaMassPars3Prong{"deltaMassPars3Prong", {defaultDeltaMassPars3Prong[0], 2, {"constant", "linear"}}, "delta mass parameters for HF 3 prong trigger mass cut"};
+  o2::framework::Configurable<o2::framework::LabeledArray<float>> sigmaPars3Prong{"sigmaPars3Prong", {defaultSigmaPars3Prong[0], 2, {"constant", "linear"}}, "sigma parameters for HF 3 prong trigger mass cut"};
+
+  /// Mass selection of D+ candidates to build B0 candidates
+  /// \param pTrackSameChargeFirst is the first same-charge track momentum
+  /// \param pTrackSameChargeFirst is the second same-charge track momentum
+  /// \param pTrackSameChargeFirst is the opposite charge track momentum
+  /// \param ptD is the pt of the D+ meson candidate
+  /// \return true if D+ passes selection
+  bool isSelectedDplusInMassRange(const float& invMassDplus, const float& ptD)
+  {
+    float peakMean = (ptD < pTMaxDeltaMass) ? ((o2::constants::physics::MassDPlus + deltaMassPars3Prong->get("constant")) + deltaMassPars3Prong->get("linear") * ptD) : o2::constants::physics::MassDPlus;
+    float peakWidth = sigmaPars3Prong->get("constant") + sigmaPars3Prong->get("linear") * ptD;
+
+    if (std::fabs(invMassDplus - peakMean) > nSigma * peakWidth && ptD < pTMaxMassCut) {
+      return false;
+    }
+    return true;
+  }
+};
 } // namespace o2::analysis
 
 #endif // PWGHF_UTILS_UTILSANALYSIS_H_