TITLE:   GCN CIRCULAR
NUMBER:  33163
SUBJECT: Trigger 1148770: Swift detection of Cyg X-1 due to Star Tracker loss of lock
DATE:    23/01/13 00:49:45 GMT
FROM:    Tyler Parsotan at UMBC/GSFC/CRESST II  <parsotat@umbc.edu>

C. Gronwall (PSU) and T. M. Parsotan (GSFC/UMBC/CRESSTII) report on
behalf of the Neil Gehrels Swift Observatory Team:

At 00:27:49 UT, the Swift Burst Alert Telescope (BAT) was triggered on a noise
event (trigger=1148770). The BAT on-board calculated location is 
RA, Dec 299.512, +35.075, which is 
   RA(J2000)  =  19h 58m 03s
   Dec(J2000) = +35d 04' 288"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a signal which is typical
for a rate trigger however there were  Star Tracker problems.