First prototype of strangeness tracking workflow

CODEOWNERS

@@ -73,6 +73,7 @@
 /Detectors/ZDC                     @coppedis
 /Detectors/CTF                     @shahor02
 /Detectors/Raw                     @shahor02
+/Detectors/StrangenessTracking     @mconcas @mpuccio @fmazzasc
 
 /EventVisualisation  @jmyrcha
 #/EventVisualisation/Base

DataFormats/Reconstruction/src/ReconstructionDataFormatsLinkDef.h

@@ -24,6 +24,8 @@
 #pragma link C++ class o2::track::TrackParCovD + ;
 #pragma link C++ class o2::track::TrackParCov + ;
 #pragma link C++ class o2::track::TrackParametrizationWithError < float> + ;
+#pragma link C++ class std::vector < o2::track::TrackParametrizationWithError < float>> + ;
+
 #pragma link C++ class o2::track::TrackParametrizationWithError < double> + ;
 #pragma link C++ class o2::track::TrackParFwd + ;
 #pragma link C++ class o2::track::PID + ;

Detectors/CMakeLists.txt

@@ -36,7 +36,7 @@ add_subdirectory(FOCAL)
 add_subdirectory(GlobalTracking)
 add_subdirectory(GlobalTrackingWorkflow)
 add_subdirectory(Vertexing)
-
+add_subdirectory(StrangenessTracking)
 if(BUILD_ANALYSIS)
   add_subdirectory(AOD)
 endif()

Detectors/StrangenessTracking/CMakeLists.txt

@@ -0,0 +1,14 @@
+# Copyright 2019-2020 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.
+
+add_subdirectory(workflow)
+add_subdirectory(tracking)
+add_subdirectory(macros)

Detectors/StrangenessTracking/macros/CMakeLists.txt

@@ -0,0 +1,10 @@
+o2_add_test_root_macro(XiTrackingStudy.C
+                       PUBLIC_LINK_LIBRARIES O2::MathUtils
+                                             O2::ITSBase
+                                             O2::ITSMFTReconstruction
+                                             O2::ITSMFTSimulation
+                                             O2::DataFormatsITSMFT
+                                             O2::DataFormatsITS
+                                             O2::SimulationDataFormat
+                                             O2::StrangenessTracking
+                       LABELS strangeness-tracking)

Detectors/StrangenessTracking/tracking/CMakeLists.txt

@@ -0,0 +1,32 @@
+# Copyright 2019-2020 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.
+
+o2_add_library(StrangenessTracking
+               SOURCES src/StrangenessTracker.cxx
+                       src/StrangenessTrackingConfigParam.cxx
+               PUBLIC_LINK_LIBRARIES O2::MathUtils
+                                             O2::ITSBase
+                                             O2::ITSMFTReconstruction
+                                             O2::ITSMFTSimulation
+                                             O2::DataFormatsITSMFT
+                                             O2::DataFormatsITS
+                                             O2::SimulationDataFormat
+                                             O2::DetectorsVertexing
+                                             O2::ReconstructionDataFormats
+               )
+
+o2_target_root_dictionary(StrangenessTracking
+               HEADERS include/StrangenessTracking/StrangenessTrackingConfigParam.h
+                       include/StrangenessTracking/IndexTableUtils.h
+                       include/StrangenessTracking/StrangenessTracker.h
+
+
+               LINKDEF src/StrangenessTrackingLinkDef.h)

Detectors/StrangenessTracking/tracking/include/StrangenessTracking/IndexTableUtils.h

@@ -0,0 +1,88 @@
+// Copyright 2019-2020 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 IndexTableUtils.h
+/// \brief
+///
+#ifndef STRTRACKING_INCLUDE_INDEXTABLEUTILS_H_
+#define STRTRACKING_INCLUDE_INDEXTABLEUTILS_H_
+
+#include "TMath.h"
+
+namespace o2
+{
+namespace strangeness_tracking
+{
+
+struct IndexTableUtils {
+  int getEtaBin(float eta);
+  int getPhiBin(float phi);
+  int getBinIndex(float eta, float phi);
+  std::vector<int> getBinRect(float eta, float phi, float deltaEta, float deltaPhi);
+  int mEtaBins = 64, mPhiBins = 64;
+  float minEta = -1.5, maxEta = 1.5;
+  float minPhi = 0., maxPhi = 2 * TMath::Pi();
+};
+
+inline int IndexTableUtils::getEtaBin(float eta)
+{
+  float deltaEta = (maxEta - minEta) / (mEtaBins);
+  int bEta = (eta - minEta) / deltaEta; // bins recentered to 0
+  return bEta;
+};
+
+inline int IndexTableUtils::getPhiBin(float phi)
+{
+  float deltaPhi = (maxPhi - minPhi) / (mPhiBins);
+  int bPhi = (phi - minPhi) / deltaPhi; // bin recentered to 0
+  return bPhi;
+}
+
+inline int IndexTableUtils::getBinIndex(float eta, float phi)
+{
+  float deltaPhi = (maxPhi - minPhi) / (mPhiBins);
+  float deltaEta = (maxEta - minEta) / (mEtaBins);
+  int bEta = getEtaBin(eta);
+  int bPhi = getPhiBin(phi);
+  return (bEta >= mEtaBins || bPhi >= mPhiBins || bEta < 0 || bPhi < 0) ? mEtaBins * mPhiBins : bEta + mEtaBins * bPhi;
+}
+
+inline std::vector<int> IndexTableUtils::getBinRect(float eta, float phi, float deltaEta, float deltaPhi)
+{
+  std::vector<int> idxVec;
+  int centralBin = getBinIndex(eta, phi);
+  if (centralBin == mPhiBins * mEtaBins) { // condition for overflows
+    idxVec.push_back(centralBin);
+    return idxVec;
+  }
+  int minEtaBin = TMath::Max(0, getEtaBin(eta - deltaEta));
+  int maxEtaBin = getEtaBin(eta + deltaEta);
+  int minPhiBin = TMath::Max(0, getPhiBin(phi - deltaPhi));
+  int maxPhiBin = getPhiBin(phi + deltaPhi);
+
+  for (int iPhi{minPhiBin}; iPhi <= maxPhiBin; iPhi++) {
+    if (iPhi >= mPhiBins) {
+      break;
+    }
+    for (int iEta{minEtaBin}; iEta <= maxEtaBin; iEta++) {
+      if (iEta >= mEtaBins) {
+        break;
+      }
+      idxVec.push_back(iEta + mEtaBins * iPhi);
+    }
+  }
+  return idxVec;
+};
+
+} // namespace strangeness_tracking
+} // namespace o2
+
+#endif

Detectors/StrangenessTracking/tracking/include/StrangenessTracking/StrangenessTracker.h

@@ -0,0 +1,140 @@
+// Copyright 2019-2020 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 StrangenessTracker.h
+/// \brief
+///
+
+#ifndef _ALICEO2_STRANGENESS_TRACKER_
+#define _ALICEO2_STRANGENESS_TRACKER_
+
+#include <gsl/gsl>
+#include <TLorentzVector.h>
+#include "TMath.h"
+#include "StrangenessTracking/IndexTableUtils.h"
+#include "StrangenessTracking/StrangenessTrackingConfigParam.h"
+#include "ReconstructionDataFormats/PID.h"
+#include "ReconstructionDataFormats/V0.h"
+#include "ReconstructionDataFormats/Cascade.h"
+
+#include "DataFormatsITS/TrackITS.h"
+#include "ITSBase/GeometryTGeo.h"
+#include "ReconstructionDataFormats/Track.h"
+#include "DataFormatsITSMFT/CompCluster.h"
+
+#include "DetectorsVertexing/DCAFitterN.h"
+#include "DetectorsBase/Propagator.h"
+
+namespace o2
+{
+namespace strangeness_tracking
+{
+
+enum kPartType { kV0,
+                 kCascade,
+                 kThreeBody };
+
+struct ClusAttachments {
+
+  std::array<unsigned int, 7> arr;
+};
+
+struct StrangeTrack {
+  kPartType mPartType;
+  o2::track::TrackParCovF mMother;
+  int mITSRef = -1;
+  int mDecayRef = -1;
+  std::array<float, 3> decayVtx;
+  std::array<float, 3> decayMom;
+  float mInvMass;
+  float mMatchChi2;
+  float mTopoChi2;
+};
+
+class StrangenessTracker
+{
+ public:
+  using PID = o2::track::PID;
+  using TrackITS = o2::its::TrackITS;
+  using ITSCluster = o2::BaseCluster<float>;
+  using V0 = o2::dataformats::V0;
+  using Cascade = o2::dataformats::Cascade;
+  using GIndex = o2::dataformats::VtxTrackIndex;
+  using DCAFitter2 = o2::vertexing::DCAFitterN<2>;
+  using DCAFitter3 = o2::vertexing::DCAFitterN<3>;
+
+  StrangenessTracker() = default;
+  ~StrangenessTracker() = default;
+
+  void initialise();
+  void process();
+
+  std::vector<ClusAttachments>& getClusAttachments() { return mClusAttachments; };
+  std::vector<StrangeTrack>& getStrangeTrackVec() { return mStrangeTrackVec; };
+
+  float getBz() const { return mBz; }
+  void setBz(float d) { mBz = d; }
+  void setCorrType(const o2::base::PropagatorImpl<float>::MatCorrType& type) { mCorrType = type; }
+
+  void setupFitters()
+  {
+    mFitterV0.setBz(mBz);
+    mFitter3Body.setBz(mBz);
+    mFitterV0.setUseAbsDCA(true);
+    mFitter3Body.setUseAbsDCA(true);
+  }
+
+  bool loadData(gsl::span<const o2::its::TrackITS> InputITStracks, std::vector<ITSCluster>& InputITSclusters, gsl::span<const int> InputITSidxs, gsl::span<const V0> InputV0tracks, gsl::span<const Cascade> InputCascadeTracks, o2::its::GeometryTGeo* geomITS);
+  double calcV0alpha(const V0& v0);
+  std::vector<ITSCluster> getTrackClusters();
+  float getMatchingChi2(o2::track::TrackParCovF, const TrackITS ITSTrack, ITSCluster matchingClus);
+  bool recreateV0(const o2::track::TrackParCov& posTrack, const o2::track::TrackParCov& negTrack, V0& newV0);
+
+  bool updateTrack(const ITSCluster& clus, o2::track::TrackParCov& track);
+  bool matchDecayToITStrack(float decayR);
+
+ protected:
+  gsl::span<const o2::its::TrackITS> mInputITStracks; // input ITS tracks
+  std::vector<int> mTracksIdxTable;                   // index table for ITS tracks
+  std::vector<ITSCluster> mInputITSclusters;          // input ITS clusters
+  gsl::span<const int> mInputITSidxs;                 // input ITS track-cluster indexes
+  gsl::span<const V0> mInputV0tracks;                 // input V0 of decay daughters
+  gsl::span<const Cascade> mInputCascadeTracks;       // input V0 of decay daughters
+
+  std::vector<o2::its::TrackITS> mSortedITStracks; // sorted ITS tracks
+  std::vector<int> mSortedITSindexes;              // indexes of sorted ITS tracks
+  IndexTableUtils mUtils;                          // structure for computing eta/phi matching selections
+
+  std::vector<StrangeTrack> mStrangeTrackVec;    // structure containing updated mother and daughter tracks
+  std::vector<ClusAttachments> mClusAttachments; // # of attached tracks, 1 for mother, 2 for daughter
+
+  const StrangenessTrackingParamConfig* mStrParams = nullptr;
+  float mBz = -5; // Magnetic field
+
+  DCAFitter2 mFitterV0;    // optional DCA Fitter for recreating V0 with hypertriton mass hypothesis
+  DCAFitter3 mFitter3Body; // optional DCA Fitter for final 3 Body refit
+
+  o2::base::PropagatorImpl<float>::MatCorrType mCorrType = o2::base::PropagatorImpl<float>::MatCorrType::USEMatCorrNONE; // use mat correction
+  o2::its::GeometryTGeo* mGeomITS;                                                                                       // ITS geometry
+
+  std::vector<o2::track::TrackParCovF> mDaughterTracks; // vector of daughter tracks
+  StrangeTrack mStrangeTrack;                           // structure containing updated mother and daughter track refs
+  ClusAttachments mStructClus;                          // # of attached tracks, 1 for mother, 2 for daughter
+  o2::its::TrackITS mITStrack;                          // ITS track
+  std::array<GIndex, 2> mV0dauIDs;                      // V0 daughter IDs
+
+  ClassDefNV(StrangenessTracker, 1);
+};
+
+} // namespace strangeness_tracking
+} // namespace o2
+
+#endif //  _ALICEO2_STRANGENESS_TRACKER_

Detectors/StrangenessTracking/tracking/include/StrangenessTracking/StrangenessTrackingConfigParam.h

@@ -0,0 +1,40 @@
+// Copyright 2019-2020 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 StrangenessTrackingConfigParam.h
+/// \brief
+
+#ifndef ALICEO2_STRANGENESS_TRACKING_PARAM_H_
+#define ALICEO2_STRANGENESS_TRACKING_PARAM_H_
+
+#include "CommonUtils/ConfigurableParam.h"
+#include "CommonUtils/ConfigurableParamHelper.h"
+
+namespace o2
+{
+namespace strangeness_tracking
+{
+
+struct StrangenessTrackingParamConfig : public o2::conf::ConfigurableParamHelper<StrangenessTrackingParamConfig> {
+
+  // parameters
+  float mRadiusTolIB = .3;   // Radius tolerance for matching V0s in the IB
+  float mRadiusTolOB = .1;   // Radius tolerance for matching V0s in the OB
+  float mPhiBinSize = 0.1;   // Phi bin size for the matching grid
+  float mEtaBinSize = 0.1;   // Eta bin size for the matching grid
+  float mMinMotherClus = 3.; // minimum number of cluster to be attached to the mother
+  float mMaxChi2 = 50;       // Maximum matching chi2
+
+  O2ParamDef(StrangenessTrackingParamConfig, "strtracker");
+};
+
+} // namespace strangeness_tracking
+} // namespace o2
+#endif