update neck tube cut to include time difference changes due to cable changes

1 files changed, 18 insertions, 1 deletions

diff --git a/src/dc.c b/src/dc.c
index ff99f3f..7242617 100644
--- a/src/dc.c
+++ b/src/dc.c
@@ -453,6 +453,20 @@ int qvnhit(event *ev)
     return qhl_ratio < QRATIO_THRESHOLD;
 }
 
+/* Returns the time difference between the neck PMT hit and the average ECA
+ * time of the PSUP PMTs required to tag an event as a neck event.
+ *
+ * These values come from the neck tube cut table in prod/filter_flth.dat. */
+double get_neck_tube_cut_time_diff(event *ev)
+{
+    if (ev->dte < 19991216 || (ev->dte == 19991216 && ev->hmsc < 20370000))
+        return 70.0;
+    else if (ev->dte < 20040923 || (ev->dte < 20040923 && ev->hmsc < 100222))
+        return 15.0;
+    else
+        return -85.0;
+}
+
 /* Returns 1 if the event is classified as a neck event. The definition of
  * a neck event is a combination of the neck flag in the DAMN word:
  *
@@ -480,6 +494,7 @@ int is_neck_event(event *ev)
     int high_charge;
     double avg_ept_psup;
     int nhit, nhit_bottom;
+    double time_diff;
 
     /* First, we compute the average ECA time for all the PSUP PMTs with z <= 0. */
 
@@ -501,6 +516,8 @@ int is_neck_event(event *ev)
 
     avg_ept_psup /= nhit;
 
+    time_diff = get_neck_tube_cut_time_diff(ev);
+
     /* Now, we check if two or more neck tubes fired *or* a single neck tube
      * fired with a high charge and 70 ns before the average time of the normal
      * PMTs. */
@@ -523,7 +540,7 @@ int is_neck_event(event *ev)
              * of the PSUP PMTS with z les than 0." When does this change take
              * place? */
             if ((ev->pmt_hits[i].ehs > 70 || ev->pmt_hits[i].ehs < -110) &&
-                (ev->pmt_hits[i].ept < avg_ept_psup - 70.0)) high_charge = 1;
+                (ev->pmt_hits[i].ept < avg_ept_psup - time_diff)) high_charge = 1;
             break;
         case PMT_NORMAL:
             nhit += 1;