From fbf4d3f14f546888384e794950b1ff9f89e13279 Mon Sep 17 00:00:00 2001
From: creetz16 <carolina@reetz.name>
Date: Mon, 10 Aug 2026 14:23:44 +0200
Subject: [PATCH] Add MC table to store ITS track DCA to SV

---
 PWGLF/DataModel/Vtx3BodyTables.h              |  8 +++---
 .../Nuspex/trackedHypertritonRecoTask.cxx     | 26 ++++++++++++++++---
 2 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/PWGLF/DataModel/Vtx3BodyTables.h b/PWGLF/DataModel/Vtx3BodyTables.h
index a2c8ad8a396..76a89e80193 100644
--- a/PWGLF/DataModel/Vtx3BodyTables.h
+++ b/PWGLF/DataModel/Vtx3BodyTables.h
@@ -141,8 +141,8 @@ DECLARE_SOA_COLUMN(IsReco, isreco, int);               //! flag if candidate was
 DECLARE_SOA_COLUMN(MotherLabel, motherLabel, int);     //! label of the mother particle (signal: MC index, bkg: negative value)
 
 // strangeness tracking information
-DECLARE_SOA_COLUMN(ITSTrackDCAXYToSVXY, itsTrackDcaXYToSv, float); //! DCAxy of ITS track to SV
-DECLARE_SOA_COLUMN(ITSTrackDCAZToSVXY, itsTrackDcaZToSv, float);   //! DCAz of ITS track to SV
+DECLARE_SOA_COLUMN(ITSTrackDCAXYToSV, itsTrackDcaXYToSv, float); //! DCAxy of ITS track to SV
+DECLARE_SOA_COLUMN(ITSTrackDCAZToSV, itsTrackDcaZToSv, float);   //! DCAz of ITS track to SV
 
 // Derived expressions
 // Momenta
@@ -264,8 +264,8 @@ DECLARE_SOA_TABLE(Vtx3BodyCovs, "AOD", "VTX3BODYCOV", //!
 
 // strangeness tracked extra table
 DECLARE_SOA_TABLE(Vtx3BodyTrackedInfo, "AOD", "VTX3BODYTR", //!
-                  vtx3body::ITSTrackDCAXYToSVXY,
-                  vtx3body::ITSTrackDCAZToSVXY);
+                  vtx3body::ITSTrackDCAXYToSV,
+                  vtx3body::ITSTrackDCAZToSV);
 
 // MC candidate table for analysis
 DECLARE_SOA_TABLE(McVtx3BodyDatas, "AOD", "MC3BODYDATA", //!
diff --git a/PWGLF/TableProducer/Nuspex/trackedHypertritonRecoTask.cxx b/PWGLF/TableProducer/Nuspex/trackedHypertritonRecoTask.cxx
index bb15833d0e1..d45040524d8 100644
--- a/PWGLF/TableProducer/Nuspex/trackedHypertritonRecoTask.cxx
+++ b/PWGLF/TableProducer/Nuspex/trackedHypertritonRecoTask.cxx
@@ -773,6 +773,16 @@ struct TrackedHypertritonRecoTask {
     return deuteronTOFPIDMC.GetTOFNSigma(tofResponse, track, originalCollision, collision);
   }
 
+  template <class TTracksTo, typename TTracked3body>
+  std::array<float, 2> getItsTrackDCAToSV(TTracked3body tracked3Body)
+  {
+    const auto itsTrack = tracked3Body.template itsTrack_as<TTracksTo>();
+    auto itsTrackParCov = getTrackParCov(itsTrack);
+    std::array<float, 2> dcaInfo{};
+    o2::base::Propagator::Instance()->propagateToDCABxByBz({builder3Body.decay3body.position[0], builder3Body.decay3body.position[1], builder3Body.decay3body.position[2]}, itsTrackParCov, 2.f, fitter2Body.getMatCorrType(), &dcaInfo);
+    return dcaInfo;
+  }
+
   void fillThreeBodyTables()
   {
     const auto& candidate = builder3Body.decay3body;
@@ -831,6 +841,8 @@ struct TrackedHypertritonRecoTask {
                     static_cast<int>(info.isReco), info.motherLabel, info.motherPdgCode,
                     info.protonPdgCode, info.pionPdgCode, info.deuteronPdgCode,
                     info.isDeuteronPrimary, static_cast<int>(info.survivedEventSelection));
+    vtx3BodyCovs(candidate.covProton.data(), candidate.covPion.data(), candidate.covDeuteron.data(), candidate.covariance.data());
+    vtx3BodyTrackedInfo(candidate.itsTrackDCAToSV[0], candidate.itsTrackDCAToSV[1]);
   }
 
   void fillGeneratedThreeBodyMCTable(ThreeBodyMCInfo const& info)
@@ -926,10 +938,7 @@ struct TrackedHypertritonRecoTask {
                                                 threeBody.useSelections, threeBody.useChi2Selection, threeBody.useTPCforPion,
                                                 threeBody.acceptTPCOnly, threeBody.askOnlyITSMatch, threeBody.calculateCovariance)) {
         // get DCA of ITS track to SV
-        const auto itsTrack = tracked3Body.itsTrack_as<Tracks>();
-        auto itsTrackParCov = getTrackParCov(itsTrack);
-        std::array<float, 2> dcaInfoItsTrack{};
-        o2::base::Propagator::Instance()->propagateToDCABxByBz({builder3Body.decay3body.position[0], builder3Body.decay3body.position[1], builder3Body.decay3body.position[2]}, itsTrackParCov, 2.f, fitter2Body.getMatCorrType(), &dcaInfoItsTrack);
+        std::array<float, 2> dcaInfoItsTrack = getItsTrackDCAToSV<Tracks>(tracked3Body);
         builder3Body.decay3body.itsTrackDCAToSV[0] = dcaInfoItsTrack[0];
         builder3Body.decay3body.itsTrackDCAToSV[1] = dcaInfoItsTrack[1];
         if (threeBody.useSelections && (std::abs(builder3Body.decay3body.itsTrackDCAToSV[0]) > threeBody.maxITSDCAxytrackToSV || std::abs(builder3Body.decay3body.itsTrackDCAToSV[1]) > threeBody.maxITSDCAztrackToSV)) {
@@ -1025,6 +1034,15 @@ struct TrackedHypertritonRecoTask {
       if (mcInfo.motherLabel < 0 && !mc.storeBackground) {
         continue;
       }
+
+      // get DCA of ITS track to SV
+      std::array<float, 2> dcaInfoItsTrack = getItsTrackDCAToSV<TracksMC>(tracked3Body);
+      builder3Body.decay3body.itsTrackDCAToSV[0] = dcaInfoItsTrack[0];
+      builder3Body.decay3body.itsTrackDCAToSV[1] = dcaInfoItsTrack[1];
+      if (threeBody.useSelections && (std::abs(builder3Body.decay3body.itsTrackDCAToSV[0]) > threeBody.maxITSDCAxytrackToSV || std::abs(builder3Body.decay3body.itsTrackDCAToSV[1]) > threeBody.maxITSDCAztrackToSV)) {
+        continue;
+      }
+
       fillThreeBodyMCTable(mcInfo);
       if (mcInfo.motherLabel >= 0) {
         reconstructedThreeBody[mcInfo.motherLabel] = true;