Move the track extrapolation from dipole edge to z=800

JeffersonLab · Apr 15, 2024 · d43a25d · d43a25d
1 parent 3e40b0f
commit d43a25d
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Showing 2 changed files with 10 additions and 8 deletions.
diff --git a/tracking/src/main/java/org/hps/recon/tracking/BeamlineConstants.java b/tracking/src/main/java/org/hps/recon/tracking/BeamlineConstants.java
@@ -18,6 +18,8 @@ private BeamlineConstants() {
 
     public static final double DIPOLE_EDGE_ENG_RUN = 457.2 + 1080 / 2;
 
+    public static final double ECAL_TRACK_EXTRAPOLATION_START_Z = 800; // Starting point for track extrapolation to ECAL -- MWH 2024/4/15
+
     public static final double HODO_L1_ZPOS = 1103.5; //extracted from detector element mg--7/17/2019
     public static final double HODO_L2_ZPOS = 1115.5; //extracted from detector element mg--7/17/2019
 

diff --git a/tracking/src/main/java/org/hps/recon/tracking/TrackUtils.java b/tracking/src/main/java/org/hps/recon/tracking/TrackUtils.java
@@ -648,7 +648,7 @@ public static BaseTrackState getTrackExtrapAtEcal(TrackState track, FieldMap fie
         if (4441 < runNumber && runNumber < 8100)
             zAtEcal = BeamlineConstants.ECAL_FACE_ENGINEERING_RUNS;
 
-        BaseTrackState bts = extrapolateTrackUsingFieldMap(track, BeamlineConstants.DIPOLE_EDGE_ENG_RUN, zAtEcal, 5.0, fieldMap);
+        BaseTrackState bts = extrapolateTrackUsingFieldMap(track, BeamlineConstants.ECAL_TRACK_EXTRAPOLATION_START_Z, zAtEcal, 5.0, fieldMap);
         bts.setLocation(TrackState.AtCalorimeter);
         return bts;
     }
@@ -663,9 +663,9 @@ public static BaseTrackState getTrackExtrapAtEcalRK(TrackState ts, FieldMap fM,
         if (4441 < runNumber && runNumber < 8100)
             zAtEcal = BeamlineConstants.ECAL_FACE_ENGINEERING_RUNS;
 
-        Hep3Vector startPos = extrapolateHelixToXPlane(ts, BeamlineConstants.DIPOLE_EDGE_ENG_RUN);
+        Hep3Vector startPos = extrapolateHelixToXPlane(ts, BeamlineConstants.ECAL_TRACK_EXTRAPOLATION_START_Z);
         Hep3Vector startPosTrans = CoordinateTransformations.transformVectorToDetector(startPos);
-        double distanceZ = zAtEcal - BeamlineConstants.DIPOLE_EDGE_ENG_RUN;
+        double distanceZ = zAtEcal - BeamlineConstants.ECAL_TRACK_EXTRAPOLATION_START_Z;
         double charge = -1.0 * Math.signum(getR(ts));
 
         org.hps.util.Pair<Hep3Vector, Hep3Vector> RKresults = extrapolateTrackUsingFieldMapRK(ts, startPosTrans, distanceZ, stepSize, fM);
@@ -711,14 +711,14 @@ public static BaseTrackState getTrackExtrapAtHodoRK(TrackState ts, FieldMap fM,
     }
 
     public static BaseTrackState getTrackExtrapAtHodoRK(TrackState ts, FieldMap fM, double stepSize, int hodoLayer) {
-        Hep3Vector startPos = extrapolateHelixToXPlane(ts, BeamlineConstants.DIPOLE_EDGE_ENG_RUN);
+        Hep3Vector startPos = extrapolateHelixToXPlane(ts, BeamlineConstants.ECAL_TRACK_EXTRAPOLATION_START_Z);
         Hep3Vector startPosTrans = CoordinateTransformations.transformVectorToDetector(startPos);
         double distZHodo = BeamlineConstants.HODO_L1_ZPOS;
         int hodoTrackStateIndex = 0;
         if (hodoLayer == 2) {
             distZHodo = BeamlineConstants.HODO_L2_ZPOS; //            hodoTrackStateIndex = 7;
         }
-        double distanceZ = distZHodo - BeamlineConstants.DIPOLE_EDGE_ENG_RUN;
+        double distanceZ = distZHodo - BeamlineConstants.ECAL_TRACK_EXTRAPOLATION_START_Z;
         double charge = -1.0 * Math.signum(getR(ts));
 
         org.hps.util.Pair<Hep3Vector, Hep3Vector> RKresults = extrapolateTrackUsingFieldMapRK(ts, startPosTrans, distanceZ, stepSize, fM);
@@ -851,9 +851,9 @@ public static Hep3Vector extrapolateTrack(TrackState track, double z) {
 
         Hep3Vector trackPosition;
         double dz;
-        if (z >= BeamlineConstants.DIPOLE_EDGE_ENG_RUN) {
-            trackPosition = extrapolateHelixToXPlane(track, BeamlineConstants.DIPOLE_EDGE_ENG_RUN);
-            dz = z - BeamlineConstants.DIPOLE_EDGE_ENG_RUN;
+        if (z >= BeamlineConstants.ECAL_TRACK_EXTRAPOLATION_START_Z) {
+            trackPosition = extrapolateHelixToXPlane(track, BeamlineConstants.ECAL_TRACK_EXTRAPOLATION_START_Z);
+            dz = z - BeamlineConstants.ECAL_TRACK_EXTRAPOLATION_START_Z;
         } else if (z <= BeamlineConstants.DIPOLE_EDGELOW_TESTRUN) {
             trackPosition = extrapolateHelixToXPlane(track, BeamlineConstants.DIPOLE_EDGELOW_TESTRUN);
             dz = z - trackPosition.x();