[PWGEM/Dilepton] reduce number of calling propagateMuon

PWGEM/Dilepton/Core/DimuonCut.h

@@ -1,4 +1,4 @@
 // 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.
 //
@@ -8,7 +8,7 @@
 // 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.
 
 //
 // Class for dimuon selection
 //
@@ -32,7 +32,7 @@
 #include <utility>
 #include <vector>
 
 using namespace o2::aod::pwgem::dilepton::utils::emtrackutil;
 
 class DimuonCut : public TNamed
 {
@@ -67,7 +67,7 @@
   };
 
   template <typename TPair>
   bool IsSelected(TPair const& pair) const
   {
     auto t1 = std::get<0>(pair);
     auto t2 = std::get<1>(pair);
@@ -194,7 +194,7 @@
         return track.nClusters() >= mMinNClustersMCHMID;
 
       case DimuonCuts::kChi2:
-        return track.chi2() / (2.f * (track.nClusters() + track.nClustersMFT()) - 5.f) < mMaxChi2;
+        return (track.trackType() == static_cast<uint8_t>(o2::aod::fwdtrack::ForwardTrackTypeEnum::GlobalMuonTrack) ? track.chi2() / (2.f * (track.nClusters() + track.nClustersMFT()) - 5.f) : track.chi2()) < mMaxChi2;
 
       case DimuonCuts::kMatchingChi2MCHMFT:
         return track.chi2MatchMCHMFT() < mMaxMatchingChi2MCHMFT;
@@ -236,7 +236,7 @@
   void SetTrackType(int track_type); // 0: MFT-MCH-MID (global muon), 3: MCH-MID (standalone muon)
   void SetTrackPtRange(float minPt = 0.f, float maxPt = 1e10f);
   void SetTrackEtaRange(float minEta = -1e10f, float maxEta = 1e10f);
   void SetTrackPhiRange(float minPhi = 0.f, float maxPhi = 2.f * M_PI);
   void SetNClustersMFT(int min, int max);
   void SetNClustersMCHMID(int min, int max);
   void SetChi2(float min, float max);
@@ -261,7 +261,7 @@
   // kinematic cuts
   float mMinTrackPt{0.f}, mMaxTrackPt{1e10f};        // range in pT
   float mMinTrackEta{-1e10f}, mMaxTrackEta{1e10f};   // range in eta
   float mMinTrackPhi{0.f}, mMaxTrackPhi{2.f * M_PI}; // range in phi
 
   // track quality cuts
   int mTrackType{3};

PWGEM/Dilepton/TableProducer/skimmerPrimaryMuon.cxx

@@ -183,7 +183,7 @@ struct skimmerPrimaryMuon {
       if (maxDCAxy < dcaXY) {
         return false;
       }
-      if (chi2_per_ndf < 0.f || maxChi2GL < chi2_per_ndf) {
+      if (maxChi2GL < chi2_per_ndf) {
         return false;
       }
       if (rAtAbsorberEnd < minRabsGL || maxRabs < rAtAbsorberEnd) {
@@ -193,7 +193,7 @@ struct skimmerPrimaryMuon {
       if (eta < minEtaSA || maxEtaSA < eta) {
         return false;
       }
-      if (chi2_per_ndf < 0.f || maxChi2SA < chi2_per_ndf) {
+      if (maxChi2SA < chi2_per_ndf) {
         return false;
       }
     } else {
@@ -214,14 +214,17 @@ struct skimmerPrimaryMuon {
       return;
     }
 
-    o2::dataformats::GlobalFwdTrack propmuonAtPV = propagateMuon(fwdtrack, collision, propagationPoint::kToVertex);
-    o2::dataformats::GlobalFwdTrack propmuonAtDCA = propagateMuon(fwdtrack, collision, propagationPoint::kToDCA);
+    if (fwdtrack.chi2() < 0.f) { // this should never happen. only for protection.
+      return;
+    }
 
+    o2::dataformats::GlobalFwdTrack propmuonAtPV = propagateMuon(fwdtrack, collision, propagationPoint::kToVertex);
     float pt = propmuonAtPV.getPt();
     float eta = propmuonAtPV.getEta();
     float phi = propmuonAtPV.getPhi();
     o2::math_utils::bringTo02Pi(phi);
 
+    o2::dataformats::GlobalFwdTrack propmuonAtDCA = propagateMuon(fwdtrack, collision, propagationPoint::kToDCA);
     float cXXatDCA = propmuonAtDCA.getSigma2X();
     float cYYatDCA = propmuonAtDCA.getSigma2Y();
     float cXYatDCA = propmuonAtDCA.getSigmaXY();
@@ -255,24 +258,41 @@ struct skimmerPrimaryMuon {
     int ndf_mchmft = 1;
 
     if (fwdtrack.trackType() == o2::aod::fwdtrack::ForwardTrackTypeEnum::GlobalMuonTrack) {
+      // apply r-absorber cut here to minimize the number of calling propagateMuon.
+      if (fwdtrack.rAtAbsorberEnd() < minRabsGL || maxRabs < fwdtrack.rAtAbsorberEnd()) {
+        return;
+      }
+
+      // apply dca cut here to minimize the number of calling propagateMuon.
+      if (maxDCAxy < dcaXY) {
+        return;
+      }
+
       const auto& mchtrack = fwdtrack.template matchMCHTrack_as<TFwdTracks>(); // MCH-MID
+      const auto& mfttrack = fwdtrack.template matchMFTTrack_as<TMFTTracks>(); // MFTsa
+      nClustersMFT = mfttrack.nClusters();
+      mftClusterSizesAndTrackFlags = mfttrack.mftClusterSizesAndTrackFlags();
+      ndf_mchmft = 2.f * (mchtrack.nClusters() + nClustersMFT) - 5.f;
+      chi2mft = mfttrack.chi2();
+      // chi2mft = mfttrack.chi2() / (2.f * nClustersMFT - 5.f);
+
+      // apply chi2/ndf cut here to minimize the number of calling propagateMuon.
+      if (maxChi2GL < fwdtrack.chi2() / ndf_mchmft) {
+        return;
+      }
+
       o2::dataformats::GlobalFwdTrack propmuonAtPV_Matched = propagateMuon(mchtrack, collision, propagationPoint::kToVertex);
       ptMatchedMCHMID = propmuonAtPV_Matched.getPt();
       etaMatchedMCHMID = propmuonAtPV_Matched.getEta();
       phiMatchedMCHMID = propmuonAtPV_Matched.getPhi();
       o2::math_utils::bringTo02Pi(phiMatchedMCHMID);
+
       o2::dataformats::GlobalFwdTrack propmuonAtDCA_Matched = propagateMuon(mchtrack, collision, propagationPoint::kToDCA);
       float dcaX_Matched = propmuonAtDCA_Matched.getX() - collision.posX();
       float dcaY_Matched = propmuonAtDCA_Matched.getY() - collision.posY();
       float dcaXY_Matched = std::sqrt(dcaX_Matched * dcaX_Matched + dcaY_Matched * dcaY_Matched);
       pDCA = mchtrack.p() * dcaXY_Matched;
 
-      const auto& mfttrack = fwdtrack.template matchMFTTrack_as<TMFTTracks>();
-      nClustersMFT = mfttrack.nClusters();
-      mftClusterSizesAndTrackFlags = mfttrack.mftClusterSizesAndTrackFlags();
-      chi2mft = mfttrack.chi2() / (2.f * nClustersMFT - 5.f);
-      ndf_mchmft = 2.f * (mchtrack.nClusters() + nClustersMFT) - 5.f;
-
       if (refitGlobalMuon) {
         eta = mfttrack.eta();
         phi = mfttrack.phi();