From d3cd63ce333e1a9b26476028b1314c190d952da0 Mon Sep 17 00:00:00 2001
From: tongtongcao <tongtongcao1@gmail.com>
Date: Tue, 24 Mar 2026 12:25:57 -0400
Subject: [PATCH] fix null issue for finalSV in KF for new HB tracking

---
 .../main/java/org/jlab/rec/dc/track/TrackCandListFinder.java    | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/reconstruction/dc/src/main/java/org/jlab/rec/dc/track/TrackCandListFinder.java b/reconstruction/dc/src/main/java/org/jlab/rec/dc/track/TrackCandListFinder.java
index 6f68d554ab..b643cfccc7 100644
--- a/reconstruction/dc/src/main/java/org/jlab/rec/dc/track/TrackCandListFinder.java
+++ b/reconstruction/dc/src/main/java/org/jlab/rec/dc/track/TrackCandListFinder.java
@@ -294,6 +294,8 @@ public List<Track> getTrackCandsAI(CrossList crossList, DCGeant4Factory DcDetect
                 
                 if(cand.get_Vtx0() != null){
                     Point3D VTCS = cand.get(cand.size()-1).getCoordsInTiltedSector(cand.get_Vtx0().x(), cand.get_Vtx0().y(), cand.get_Vtx0().z());
+                    finalSV.k = measSurfaces.size()-1;
+                    kFZRef.finalStateVec = finalSV;                    
                     double deltaPathToVtx =  kFZRef.getDeltaPathToVtx(sector, VTCS.z());
 
                     List<org.jlab.rec.dc.trajectory.StateVec> kfStateVecsAlongTrajectory = setKFStateVecsAlongTrajectory(kFZRef, deltaPathToVtx);