don't flag PMT hits based on the uncalibrated QHS for MC

1 files changed, 34 insertions, 2 deletions

diff --git a/src/zdab_utils.c b/src/zdab_utils.c
index 416bd79..6d05d96 100644
--- a/src/zdab_utils.c
+++ b/src/zdab_utils.c
@@ -45,6 +45,17 @@ size_t get_nhit(event *ev)
     return nhit;
 }
 
+/* Returns 1 if the EV is produced by MC, otherwise zero.
+ *
+ *     Data type = 10*(1=real, 2=MC)
+ *               +  1*(1=SNO, 2=miniSNO)
+ *
+ * See id_data_types in the SNOMAN companion. */
+int is_mc(EVBank *ev)
+{
+    return ev->dtp/10 == 2;
+}
+
 int get_event(zebraFile *f, event *ev, zebraBank *bev)
 {
     /* Read all the PMT banks from the zebra file and update `ev`.
@@ -58,11 +69,14 @@ int get_event(zebraFile *f, event *ev, zebraBank *bev)
     static int pmt_types[] = {PMT_NORMAL,PMT_OWL,PMT_LG,PMT_CALIBRATION,PMT_BUTT,PMT_NECK};
     static char *pmt_names[] = {"PMT","OWL","LG","FECD","BUTT","NECK"};
     char pmt_type_string[256];
+    EVBank ev_bank;
 
     for (i = 0; i < MAX_PMTS; i++) {
         ev->pmt_hits[i].hit = 0;
     }
 
+    unpack_ev(bev->data, &ev_bank);
+
     for (i = 0; i < LEN(pmt_links); i++) {
         if (bev->links[pmt_links[i]-1] == 0) continue;
 
@@ -126,13 +140,31 @@ int get_event(zebraFile *f, event *ev, zebraBank *bev)
             if (bpmt.qms)
                 ev->pmt_hits[id].flags |= PMT_FLAG_CHARGE;
 
-            /* Currently, the charge model only deals with QHS, so we flag any hits which have a bad or railed QHS value.
+            /* Currently, the charge model only deals with QHS, so we flag any
+             * hits which have a bad or railed QHS value.
              *
              * FIXME: In the future, it would be nice to use the best charge
              * word (either QHS or QLX) depending on the if QHS is railed or
              * not, but I need to do more work to see how the QLX values are
              * normalized and if the existing charge model is good enough. */
-            if (bpmt.pihs >= 4095 || bpmt.pihs < 300)
+            if (is_mc(&ev_bank))
+                /* Skip uncalibrated charge check if this is MC. The reason is
+                 * that for some reason the uncalibrator in SNOMAN needs the
+                 * QSLP tables which aren't available for most runs. According
+                 * to Chris Kyba:
+                 *
+                 * > From summer 2000 on, we never ran charge slopes. I'm not
+                 * > sure if we did at the very start in 1999, because I didn't
+                 * > always understand what was going on when I was an undergrad
+                 * > :-)
+                 *
+                 * > I never looked at the charge slope data. My best
+                 * > recollection of the uncalibrator was everyone saying "it
+                 * > doesn't work, don't try to use it".
+                 *
+                 * Therefore, we ignore it for MC. */
+                ;
+            else if(bpmt.pihs >= 4095 || bpmt.pihs < 300)
                 ev->pmt_hits[id].flags |= PMT_FLAG_CHARGE;
 
             if (pmts[id].pmt_type != pmt_types[i]) {