TITLE:   GCN CIRCULAR
NUMBER:  20982
SUBJECT: LIGO/Virgo G275404: Update on significance from offline analyses
DATE:    17/04/05 17:03:39 GMT
FROM:    Alexander H Nitz at Albert Einstein Inst/Hannover  <alex.nitz@ligo.org>

The LIGO Scientific Collaboration and Virgo report:

We report an update on the significance of the gravitational-wave trigger
G275404 (GCN 20738). This trigger was reported by the online PyCBC search
with a false alarm rate (FAR) of 6 per year; i.e. background noise in the
detectors produces 6 triggers per year as loud as G275404 in the PyCBC
low-latency search. This trigger had low significance, but passed the FAR
threshold of ~ 1 / month for generating an alert.

We have completed the offline search over the time containing G275404 using
the PyCBC (Usman et al. 2016, CQG 33, 215004) and GstLAL (Messick et al.
2016, PRD 95, 042001) searches. These offline analyses provide the final
significance for candidate events.

Neither search produced a significant trigger at the time of G275404. We
conclude that G275404 is not a trigger of interest and does not warrant
further follow-up.