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GCN Circular 9325

GRB 090509: Swift detection of a burst
2009-05-09T05:21:22Z (15 years ago)
Scott Barthelmy at NASA/GSFC <>
D. Grupe (PSU), S. D. Barthelmy (GSFC), M. M. Chester (PSU),
H. A. Krimm (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC),
D. M. Palmer (LANL), J. L. Racusin (PSU) and M. H. Siegel (PSU)
report on behalf of the Swift Team:

At 05:10:03 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090509 (trigger=351525).  Swift did not slew to this burst. 
The BAT on-board calculated location is 
RA, Dec 241.404, -28.404 which is 
   RA(J2000)  =  16h 05m 37s
   Dec(J2000) = -28d 24' 12"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows multiple peaks
with a duration of about 30 sec.  The peak count rate
was ~1300 counts/sec (15-350 keV), at ~20 sec after the trigger. 

Due to the Moon observing constraint, Swift cannot slew to the 
BAT position until May 12.  There will thus be no XRT or UVOT data 
for this trigger. 

Burst Advocate for this burst is D. Grupe (grupe AT 
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:
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