TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4355
SUBJECT: Swift Trigger 172767 is not a GRB
DATE:    05/12/15 03:49:08 GMT
FROM:    Hans Krimm at NASA-GSFC  <krimm@milkyway.gsfc.nasa.gov>

H. Krimm (GSFC/USRA), S. Barthelmy (GSFC), J. Cummings (GSFC/NRC)
and C. Markwardt (GSFC/UMD) on behalf of the Swift-BAT team:

The Swift-BAT trigger (trigger=172767) at 00:39:49 UT on 15 Dec 2005
(reported in GCN Circular 4352, Holland et al.) is not due to a GRB 
or any other astrophysical source.  Using the full event-by-event data 
from the recent telemetry downlink, all 42 events in the trigger occurred 
within a single 100 microsec bin. This trigger was due to a cosmic 
shower event in BAT.