TITLE:   GCN CIRCULAR
NUMBER:  8980
SUBJECT: GRB 090313: Swift detection of a burst
DATE:    09/03/13 09:34:52 GMT
FROM:    Jirong Mao at INAF-OAB  <jirong.mao@brera.inaf.it>

J. Mao (INAF-OAB), A. P. Beardmore (U Leicester),
P. A. Evans (U Leicester), C. Guidorzi (U Ferrara),
E. A. Hoversten (PSU), H. A. Krimm (CRESST/GSFC/USRA),
R. Margutti (Univ Bicocca&OAB), P. T. O'Brien (U Leicester),
K. L. Page (U Leicester), P. Romano (INAF-IASFPA),
T. Sakamoto (NASA/UMBC), G. Tagliaferri (INAF-OAB) and
H. Ziaeepour (UCL-MSSL) report on behalf of the Swift Team:

At 09:06:27 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090313 (trigger=346386).  The BAT on-board calculated 
location is RA, Dec 198.397, +8.107 which is 
   RA(J2000) = 13h 13m 35s
   Dec(J2000) = +08d 06' 23"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a broad series
of multiple peaks from approximately T-10 to T+40.  The peak count rate
was ~1300 counts/sec (15-350 keV), at ~4 sec after the trigger.  Since 
this was an image trigger, the light curve shows only rather weak peaks. 
We will have more information upon receipt of the BAT event data 
in a few hours. 

Due to a Moon observing constraint, Swift cannot slew to the BAT position
until 16:45 UT. There will thus be no prompt XRT or UVOT data for this trigger. 

Burst Advocate for this burst is J. Mao (jirong.mao AT brera.inaf.it). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)