TITLE:   GCN CIRCULAR
NUMBER:  28078
SUBJECT: GRB 200711A: Swift detection of a burst
DATE:    20/07/11 11:29:06 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC), E. Ambrosi (INAF-IASFPA),
S. D. Barthelmy (GSFC), A. D'Ai (INAF-IASFPA), V. D'Elia (SSDC),
J.D. Gropp (PSU), N. J. Klingler (PSU), K. L. Page (U Leicester),
D. M. Palmer (LANL) and A. Tohuvavohu (U Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 11:04:36 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200711A (trigger=981957).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 285.977, -0.136, which is 
   RA(J2000)  =  19h 03m 54s
   Dec(J2000) = -00d 08' 09"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed multiple peaks
with a duration of about 30 sec.  The peak count rate
was ~6000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 11:07:22.8 UT, 166.3 seconds after
the BAT trigger. Due to a poor slew, the promptly downlinked data only
cover 30% of the BAT error circle. No source was detected in 779 s within 
the small part of the BAT error region covered. We are waiting for the
full dataset covering the full field of view to detect and localise 
the XRT counterpart. 

UVOT took a finding chart exposure of 150 seconds with the White
filter starting 169 seconds after the BAT trigger. This is a very crowded
region with large extinction. No credible afterglow candidate has been
found in the initial data products. 

Burst Advocate for this burst is F. E. Marshall (marshall AT milkyway.gsfc.nasa.gov). 
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/)