diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/dc.c | 43 | ||||
| -rw-r--r-- | src/dc.h | 8 |
2 files changed, 51 insertions, 0 deletions
@@ -29,6 +29,47 @@ #define MAX_PAIRS 10000 +/* Returns 1 if the event is tagged as failing the ITC cut. The definition for + * the ITC cut comes from the SNOMAN companion: + * + * This tags events having fewer than 60% of the tubes within 93 ns + * coincidence ("in-time"). The number of in-time hits is the maximum + * number in any position of a 93 ns sliding window applied to the PMT time + * spectrum of the event. + * + */ +int is_itc(event *ev) +{ + size_t i, j; + double t_array[MAX_PMTS]; + int nhit, n, maxn; + double start; + + nhit = 0; + for (i = 0; i < MAX_PMTS; i++) { + /* Only loop over hit PMTs with good calibrations. */ + if (!ev->pmt_hits[i].hit || ev->pmt_hits[i].flags) continue; + + t_array[nhit++] = ev->pmt_hits[i].t; + } + + /* Sort the times. */ + gsl_sort(t_array,1,nhit); + + maxn = 0; + for (i = 0; i < nhit; i++) { + start = t_array[i]; + n = 1; + for (j = i+1; j < nhit; j++) { + if (t_array[j] < start + ITC_TIME_WINDOW) n += 1; + else break; + } + if (n > maxn) maxn = n; + } + + return maxn/(double) nhit < ITC_TIME_FRACTION; +} + /* Returns 1 if the event is tagged as failing the FTS cut. The definition for * the FTS cut comes from the SNOMAN companion: * @@ -153,6 +194,8 @@ uint32_t get_dc_word(event *ev, zebraFile *f, zebraBank *bmast, zebraBank *bev) status |= DC_OWL_TRIGGER; if (is_fts(ev)) status |= DC_FTS; + if (is_itc(ev)) + status |= DC_ITC; return status; } @@ -32,6 +32,13 @@ #define DC_OWL 0x80 #define DC_OWL_TRIGGER 0x100 #define DC_FTS 0x200 +#define DC_ITC 0x400 + +/* Length of the sliding window used in the ITC cut (ns). */ +#define ITC_TIME_WINDOW 93.0 +/* Fraction of hits which must be in a sliding window of 93 ns to pass the ITC + * cut. */ +#define ITC_TIME_FRACTION 0.6 /* Height of PMTs which are considered to be at the "bottom" of the detector * for the neck cut. Comes from the SNOOP definition of a neck event in SNO. */ @@ -64,6 +71,7 @@ /* QvNHIT ratio threshold. */ #define QRATIO_THRESHOLD 0.25 +int is_itc(event *ev); int is_fts(event *ev); int is_owl_trigger(event *ev); int is_owl(event *ev); |