SVertexer: V0 Photon tuning

Signed-off-by: Felix Schlepper <f3sch.git@outlook.com>

Detectors/Vertexing/StrangenessTracking/include/StrangenessTracking/StrangenessTrackingConfigParam.h

@@ -32,10 +32,11 @@ struct StrangenessTrackingParamConfig : public o2::conf::ConfigurableParamHelper
   float mMinMotherClus = 3.;   // minimum number of cluster to be attached to the mother
   float mMaxChi2 = 50;         // Maximum matching chi2
   bool mVertexMatching = true; // Flag to enable/disable vertex matching
+  bool mSkipTPC = true;        // Flag to enable/disable TPC only tracks
 
   O2ParamDef(StrangenessTrackingParamConfig, "strtracker");
 };
 
 } // namespace strangeness_tracking
 } // namespace o2
-#endif
+#endif

Detectors/Vertexing/StrangenessTracking/src/StrangenessTracker.cxx

@@ -112,6 +112,9 @@ void StrangenessTracker::prepareITStracks() // sort tracks by eta and phi and se
 
 void StrangenessTracker::processV0(int iv0, const V0& v0, const V0Index& v0Idx, int iThread)
 {
+  if (mStrParams->mSkipTPC && (v0Idx.getProngID(kV0DauNeg).getSource() == GIndex::TPC || v0Idx.getProngID(kV0DauPos).getSource() == GIndex::TPC)) {
+    return;
+  }
   ClusAttachments structClus;
   auto& daughterTracks = mDaughterTracks[iThread];
   daughterTracks.resize(2); // resize to 2 prongs: first positive second negative
@@ -205,10 +208,10 @@ void StrangenessTracker::processCascade(int iCasc, const Cascade& casc, const Ca
         }
         decayVtxTrackClone.getPxPyPzGlo(strangeTrack.mDecayMom);
         std::array<float, 3> momV0, mombach;
-        mFitter3Body[iThread].getTrack(0).getPxPyPzGlo(momV0);                             // V0 momentum at decay vertex
-        mFitter3Body[iThread].getTrack(1).getPxPyPzGlo(mombach);                           // bachelor momentum at decay vertex
-        strangeTrack.mMasses[0] = calcMotherMass(momV0, mombach, PID::Lambda, PID::Pion);  // Xi invariant mass at decay vertex
-        strangeTrack.mMasses[1] = calcMotherMass(momV0, mombach, PID::Lambda, PID::Kaon);  // Omega invariant mass at decay vertex
+        mFitter3Body[iThread].getTrack(0).getPxPyPzGlo(momV0);                            // V0 momentum at decay vertex
+        mFitter3Body[iThread].getTrack(1).getPxPyPzGlo(mombach);                          // bachelor momentum at decay vertex
+        strangeTrack.mMasses[0] = calcMotherMass(momV0, mombach, PID::Lambda, PID::Pion); // Xi invariant mass at decay vertex
+        strangeTrack.mMasses[1] = calcMotherMass(momV0, mombach, PID::Lambda, PID::Kaon); // Omega invariant mass at decay vertex
 
         LOG(debug) << "ITS Track matched with a Cascade decay topology ....";
         LOG(debug) << "Number of ITS track clusters attached: " << itsTrack.getNumberOfClusters();

Detectors/Vertexing/include/DetectorsVertexing/SVertexer.h

@@ -100,8 +100,12 @@ class SVertexer
     VBracket vBracket{};
     float minR = 0; // track lowest point r
     bool hasTPC = false;
-    uint8_t nITSclu = -1;
+    int8_t nITSclu = -1;
     bool compatibleProton = false; // dE/dx compatibility with proton hypothesis (FIXME: use better, uint8_t compat mask?)
+    bool hasITS() const
+    {
+      return nITSclu > 0;
+    }
   };
 
   SVertexer(bool enabCascades = true, bool enab3body = false) : mEnableCascades{enabCascades}, mEnable3BodyDecays{enab3body}
@@ -112,6 +116,7 @@ class SVertexer
   void setEnable3BodyDecays(bool v) { mEnable3BodyDecays = v; }
   void init();
   void process(const o2::globaltracking::RecoContainer& recoTracks, o2::framework::ProcessingContext& pc);
+  void produceOutput(o2::framework::ProcessingContext& pc);
   int getNV0s() const { return mNV0s; }
   int getNCascades() const { return mNCascades; }
   int getN3Bodies() const { return mN3Bodies; }
@@ -152,7 +157,7 @@ class SVertexer
   void setupThreads();
   void buildT2V(const o2::globaltracking::RecoContainer& recoTracks);
   void updateTimeDependentParams();
-  bool acceptTrack(GIndex gid, const o2::track::TrackParCov& trc) const;
+  bool acceptTrack(const GIndex gid, const o2::track::TrackParCov& trc) const;
   bool processTPCTrack(const o2::tpc::TrackTPC& trTPC, GIndex gid, int vtxid);
   float correctTPCTrack(TrackCand& trc, const o2::tpc::TrackTPC& tTPC, float tmus, float tmusErr) const;
 
@@ -193,6 +198,7 @@ class SVertexer
 
   int mNThreads = 1;
   int mNV0s = 0, mNCascades = 0, mN3Bodies = 0, mNStrangeTracks = 0;
+  float mBz = 0;
   float mMinR2ToMeanVertex = 0;
   float mMaxDCAXY2ToMeanVertex = 0;
   float mMaxDCAXY2ToMeanVertexV0Casc = 0;

Detectors/Vertexing/include/DetectorsVertexing/SVertexerParams.h

@@ -40,6 +40,7 @@ struct SVertexerParams : public o2::conf::ConfigurableParamHelper<SVertexerParam
   float minParamChange = 1e-3;  ///< stop when tracks X-params being minimized change by less that this value
   float minRelChi2Change = 0.9; ///< stop when chi2 changes by less than this value
   float maxDZIni = 5.;          ///< don't consider as a seed (circles intersection) if Z distance exceeds this
+  float maxDXYIni = 4.;         ///< don't consider as a seed (circles intersection) if XY distance exceeds this
   float maxRIni = 150;          ///< don't consider as a seed (circles intersection) if its R exceeds this
   //
   // propagation options
@@ -51,21 +52,21 @@ struct SVertexerParams : public o2::conf::ConfigurableParamHelper<SVertexerParam
   bool usePropagator = false;                                           ///< use external propagator
   bool refitWithMatCorr = false;                                        ///< refit V0 applying material corrections
   //
-  int maxPVContributors = 2;             ///< max number PV contributors to allow in V0
-  float minDCAToPV = 0.05;               ///< min DCA to PV of single track to accept
-  float minRToMeanVertex = 0.5;          ///< min radial distance of V0 from beam line (mean vertex)
-  float maxDCAXYToMeanVertex = 0.2;      ///< max DCA of V0 from beam line (mean vertex) for prompt V0 candidates
-  float maxDCAXYToMeanVertexV0Casc = 2.; ///< max DCA of V0 from beam line (mean vertex) for cascade V0 candidates
-  float maxDCAXYToMeanVertex3bodyV0 = 2; ///< max DCA of V0 from beam line (mean vertex) for 3body V0 candidates
-  float minPtV0 = 0.01;                  ///< v0 minimum pT
-  float minPtV0FromCascade = 0.3;        ///< v0 minimum pT for v0 to be used in cascading (lowest pT Run 2 lambda: 0.4)
-  float maxTglV0 = 2.;                   ///< maximum tgLambda of V0
+  int maxPVContributors = 2;              ///< max number PV contributors to allow in V0
+  float minDCAToPV = 0.05;                ///< min DCA to PV of single track to accept
+  float minRToMeanVertex = 0.5;           ///< min radial distance of V0 from beam line (mean vertex)
+  float maxDCAXYToMeanVertex = 0.2;       ///< max DCA of V0 from beam line (mean vertex) for prompt V0 candidates
+  float maxDCAXYToMeanVertexV0Casc = 2.;  ///< max DCA of V0 from beam line (mean vertex) for cascade V0 candidates
+  float maxDCAXYToMeanVertex3bodyV0 = 2.; ///< max DCA of V0 from beam line (mean vertex) for 3body V0 candidates
+  float minPtV0 = 0.01;                   ///< v0 minimum pT
+  float minPtV0FromCascade = 0.3;         ///< v0 minimum pT for v0 to be used in cascading (lowest pT Run 2 lambda: 0.4)
+  float maxTglV0 = 2.;                    ///< maximum tgLambda of V0
 
   float causalityRTolerance = 1.; ///< V0 radius cannot exceed its contributors minR by more than this value
   float maxV0ToProngsRDiff = 50.; ///< V0 radius cannot be lower than this ammount wrt minR of contributors
 
-  float minCosPAXYMeanVertex = 0.95;      ///< min cos of PA to beam line (mean vertex) in tr. plane for prompt V0 candidates
-  float minCosPAXYMeanVertexCascV0 = 0.8; ///< min cos of PA to beam line (mean vertex) in tr. plane for V0 of cascade cand.
+  float minCosPAXYMeanVertex = 0.95;       ///< min cos of PA to beam line (mean vertex) in tr. plane for prompt V0 candidates
+  float minCosPAXYMeanVertexCascV0 = 0.8;  ///< min cos of PA to beam line (mean vertex) in tr. plane for V0 of cascade cand.
   float minCosPAXYMeanVertex3bodyV0 = 0.9; ///< min cos of PA to beam line (mean vertex) in tr. plane for 3body V0 cand.
 
   float maxRToMeanVertexCascV0 = 80; // don't consider as a cascade V0 seed if above this R
@@ -83,17 +84,26 @@ struct SVertexerParams : public o2::conf::ConfigurableParamHelper<SVertexerParam
   float maxDCAZ3Body = 1.;   // max DCA of 3 body decay to PV in Z
   float minCosPACasc = 0.7;  // min cos of PA to PV for cascade candidates
   float minCosPA3body = 0.8; // min cos of PA to PV for 3body decay candidates
-  float minPtCasc = 0.01;   // cascade minimum pT
-  float maxTglCasc = 2.;    // maximum tgLambda of cascade
-  float minPt3Body = 0.01;  // minimum pT of 3body V0
-  float maxTgl3Body = 2.;   // maximum tgLambda of 3body V0
+  float minPtCasc = 0.01;    // cascade minimum pT
+  float maxTglCasc = 2.;     // maximum tgLambda of cascade
+  float minPt3Body = 0.01;   // minimum pT of 3body V0
+  float maxTgl3Body = 2.;    // maximum tgLambda of 3body V0
 
   float maxRIni3body = 90.; // don't consider as a 3body seed (circles/line intersection) if its R exceeds this
 
-  bool mExcludeTPCtracks = false; // don't loop over TPC tracks if true (if loaded, dEdx info is used instead)
-  float mTPCTrackMaxX = -1.f;     // don't use TPC standalone tracks with X exceeding this
-  float minTPCdEdx = 250;         // starting from this dEdx value, tracks with p > minMomTPCdEdx are always accepted
-  float minMomTPCdEdx = 0.8;      // minimum p for tracks with dEdx > mMinTPCdEdx to be accepted
+  // Cuts for TPC only tracks
+  bool mExcludeTPCtracks = false;  // don't loop over TPC tracks if true (if loaded, dEdx info is used instead)
+  float mTPCTrackMaxX = -1.;       // don't use TPC standalone tracks with X exceeding this;
+  float mTPCTrack2Beam = 14.f;     // straight line for TPC track back to beamline
+  bool mTPCTrackPhotonTune = true; // use TPC-only photon tuning
+  int mTPCTrackMinNClusters = -1;  // minimum number of clusters
+  float mTPCTrackXY2Radius = 90.f; // check for realistic conversion point, e.g., in material
+  float mTPCTrackD2R = 4.f;        // check for maximal distance of pairs and their radii
+  float mTPCTrackDR = 90.f;        // check if preliminary conversion point can lie somewhere reasonable
+  float minTPCdEdx = 250;          // starting from this dEdx value, tracks with p > minMomTPCdEdx are always accepted
+  float minMomTPCdEdx = 0.8;       // minimum p for tracks with dEdx > mMinTPCdEdx to be accepted
+  float maxV0TglAbsDiff = 0.05;    ///< max absolute difference in tgl for V0 for photons only
+  float maxV0PhiAbsDiff = 2.0;     ///< max absolute difference in phi for V0 for photons only
 
   uint8_t mITSSAminNclu = 6;             // global requirement of at least this many ITS clusters if no TPC info present (N.B.: affects all secondary vertexing)
   uint8_t mITSSAminNcluCascades = 6;     // require at least this many ITS clusters if no TPC info present for cascade finding.
@@ -108,10 +118,15 @@ struct SVertexerParams : public o2::conf::ConfigurableParamHelper<SVertexerParam
   float mBBpars[5] = {0.217553, 4.02762, 0.00850178, 2.33324, 0.880904};
 
   // cuts on different V0 PID params
-  bool checkV0Hypothesis = true;
-  float pidCutsPhoton[SVertexHypothesis::NPIDParams] = {0.001, 20, 0.60, 20, 0.60, 0.0, 0.0, 0.0, 0.0};                        // Photon
+  bool checkV0Hypothesis = true;                                                                                               // enable Mass Hypothesis check
+  bool checkV0AP = false;                                                                                                      // enable Armenteros-Podolanski check
+  float pidCutsPhoton[SVertexHypothesis::NPIDParams] = {0.001, 20, 0.10, 20, 0.10, 0.0, 0.0, 0.0, 0.0};                        // Photon
+  float pidCutsPhotonAP_qT = 0.04;                                                                                             // Loose Armenteros-Podolanski q_T cut for photons in case mass-hypothesis was good
   float pidCutsK0[SVertexHypothesis::NPIDParams] = {0., 20, 0., 5.0, 0.0, 2.84798e-03, 9.84206e-04, 3.31951e-03, 2.39438};     // K0
+  float pidCutsK0AP_qT = 0.6;                                                                                                  // Loose Armenteros-Podolanski q_T cut for K0s in case mass-hypothesis was good
   float pidCutsLambda[SVertexHypothesis::NPIDParams] = {0., 20, 0., 5.0, 0.0, 1.09004e-03, 2.62291e-04, 8.93179e-03, 2.83121}; // Lambda
+  float pidCutsLambdaAP_qT = 0.9;                                                                                              // Loose Armenteros-Podolanski q_T cut for Lambda in case mass-hypothesis was good
+  float pidCutsLambdaAP_a = 0.9;                                                                                               // Loose Armenteros-Podolanski alpha cut for Lambda in case mass-hypothesis was good
   float pidCutsHTriton[SVertexHypothesis::NPIDParams] = {0.0025, 14, 0.07, 14, 0.0, 0.5, 0.0, 0.0, 0.0};                       // HyperTriton
   float pidCutsHhydrog4[SVertexHypothesis::NPIDParams] = {0.0025, 14, 0.07, 14, 0.0, 0.5, 0.0, 0.0, 0.0};                      // Hyperhydrog4 - Need to update
   //