Removing interaction time for track times

- Storing track times with bunch crossing subtracted so that the float precision is sufficient
- Add debug messages

Author: njacazio

Detectors/AOD/src/AODProducerWorkflowSpec.cxx

@@ -325,23 +325,22 @@ void AODProducerWorkflowDPL::fillTrackTablesPerCollision(int collisionID,
             const auto& tofMatch = data.getTOFMatch(contributorsGID[GIndex::Source::ITSTPCTOF]);
             extraInfoHolder.tofChi2 = tofMatch.getChi2();
             const auto& tofInt = tofMatch.getLTIntegralOut();
-            float intLen = tofInt.getL();
+            const float intLen = tofInt.getL();
             extraInfoHolder.length = intLen;
             if (interactionTime > 0) {
-              extraInfoHolder.tofSignal = static_cast<float>(tofMatch.getSignal() - interactionTime);
+              extraInfoHolder.tofSignal = static_cast<float>(tofMatch.getSignal() - interactionTime * 1E3);
             }
             const float mass = o2::constants::physics::MassPionCharged; // default pid = pion
             if (tofInt.getTOF(o2::track::PID::Pion) > 0.f) {
               const float expBeta = (intLen / (tofInt.getTOF(o2::track::PID::Pion) * cSpeed));
               extraInfoHolder.tofExpMom = mass * expBeta / std::sqrt(1.f - expBeta * expBeta);
             }
-            const auto& tofCl = tofClus[contributorsGID[GIndex::Source::TOF]];
             // correct the time of the track
-            const float massZ = o2::track::PID::getMass2Z(trackPar.getPID());
-            const float energy = sqrt((massZ * massZ) + (extraInfoHolder.tofExpMom * extraInfoHolder.tofExpMom));
-            const float exp = extraInfoHolder.length * energy / (cSpeed * extraInfoHolder.tofExpMom);
-            extraInfoHolder.trackTime = (tofCl.getTime() - exp) * 1e-3; // tof time in \mus, FIXME: account for time of flight to R TOF
-            extraInfoHolder.trackTimeRes = 200e-3;                      // FIXME: calculate actual resolution (if possible?)
+            const double massZ = o2::track::PID::getMass2Z(trackPar.getPID());
+            const double energy = sqrt((massZ * massZ) + (extraInfoHolder.tofExpMom * extraInfoHolder.tofExpMom));
+            const double exp = extraInfoHolder.length * energy / (cSpeed * extraInfoHolder.tofExpMom);
+            extraInfoHolder.trackTime = static_cast<float>((tofMatch.getSignal() - exp) * 1e-3 - interactionTime); // tof time in \mus, FIXME: account for time of flight to R TOF
+            extraInfoHolder.trackTimeRes = 200e-3;                                                                 // FIXME: calculate actual resolution (if possible?)
           }
           if (src == GIndex::Source::TPCTRD || src == GIndex::Source::ITSTPCTRD) {
             const auto& trdOrig = data.getTrack<o2::trd::TrackTRD>(src, contributorsGID[src].getIndex());
@@ -1368,7 +1367,7 @@ void AODProducerWorkflowDPL::run(ProcessingContext& pc)
                      truncateFloatFraction(timeStamp.getTimeStampError() * 1E3, mCollisionPositionCov));
     auto& trackRef = primVer2TRefs[collisionID];
     // passing interaction time in [ps]
-    fillTrackTablesPerCollision(collisionID, interactionTime * 1E3, trackRef, primVerGIs, recoData, tracksCursor, tracksCovCursor, tracksExtraCursor, mftTracksCursor, fwdTracksCursor, fwdTracksCovCursor, vertex);
+    fillTrackTablesPerCollision(collisionID, interactionTime, trackRef, primVerGIs, recoData, tracksCursor, tracksCovCursor, tracksExtraCursor, mftTracksCursor, fwdTracksCursor, fwdTracksCovCursor, vertex);
     collisionID++;
   }
 

Detectors/TOF/base/src/EventTimeMaker.cxx

@@ -38,7 +38,7 @@ void computeEvTime(const std::vector<eventTimeTrack>& tracks, const std::vector<
   static constexpr float weightLimit = 1E-6; // Limit in the weights
 
   const int ntracks = tracks.size();
-  LOG(debug) << "For the collision time using " << ntracks;
+  LOG(debug) << "For the collision time using " << ntracks << " tracks";
 
   if (ntracks < 2) { // at least 2 tracks required
     LOG(debug) << "Skipping event because at least 2 tracks are required";
@@ -48,14 +48,20 @@ void computeEvTime(const std::vector<eventTimeTrack>& tracks, const std::vector<
   int hypo[MAXNTRACKINSET];
 
   int nmaxtracksinset = ntracks > 22 ? 6 : MAXNTRACKINSET; // max number of tracks in a set for event time computation
+  LOG(debug) << "nmaxtracksinset " << nmaxtracksinset;
   int ntracksinset = std::min(ntracks, nmaxtracksinset);
+  LOG(debug) << "ntracksinset " << ntracksinset;
 
   int nset = ((ntracks - 1) / ntracksinset) + 1;
+  LOG(debug) << "nset " << nset;
   int ntrackUsed = ntracks;
+  LOG(debug) << "ntrackUsed " << ntrackUsed;
 
   if (nset > maxNumberOfSets) {
     nset = maxNumberOfSets;
+    LOG(debug) << "resetting nset " << nset;
     ntrackUsed = nmaxtracksinset * nset;
+    LOG(debug) << "resetting ntrackUsed " << ntrackUsed;
   }
 
   // list of tracks in set
@@ -70,6 +76,7 @@ void computeEvTime(const std::vector<eventTimeTrack>& tracks, const std::vector<
   int status;
   // compute event time for each set
   for (int iset = 0; iset < nset; iset++) {
+    LOG(debug) << "iset " << iset << " has size " << trackInSet[iset].size();
     unsigned long bestComb = 0;
     while (!(status = getStartTimeInSet(tracks, trackInSet[iset], bestComb))) {
       ;
@@ -90,6 +97,7 @@ void computeEvTime(const std::vector<eventTimeTrack>& tracks, const std::vector<
         evtime.tracktime[index] = ctrack.mSignal - ctrack.expTimes[hypo[itrk]];
       }
     }
+    LOG(debug) << "iset " << iset << " did not have good status";
   } // end loop in set
 
   // do average among all tracks
@@ -120,8 +128,10 @@ int getStartTimeInSet(const std::vector<eventTimeTrack>& tracks, std::vector<int
 
   chi2best = 10000;
   int ntracks = trackInSet.size();
+  LOG(debug) << "Computing the start time in set with " << ntracks << " tracks";
 
   if (ntracks < 3) {
+    LOG(debug) << "Not enough tracks!";
     return 2; // no event time in the set
   }