TITLE:   GCN CIRCULAR
NUMBER:  30417
SUBJECT: GRB 210708B: Swift detection of a possible burst
DATE:    21/07/08 13:51:47 GMT
FROM:    Hans Krimm at NSF/NASA-GSFC  <hkrimm@nsf.gov>

B. Sbarufatti (PSU), P. A. Evans (U Leicester), H. A. Krimm (NSF),
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 13:23:24 UT, the Swift Burst Alert Telescope (BAT) triggered and
located possible GRB 210708B (trigger=1059494).  
The BAT on-board calculated location is 
RA, Dec 142.579, +14.471 which is 
   RA(J2000) = 09h 30m 19s
   Dec(J2000) = +14d 28' 16"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single-peaked
structure with a duration of about 100 sec.  The peak count rate
was ~1400 counts/sec (15-350 keV), at ~6 sec after the trigger. 

Due to a Sun observing constraint, Swift cannot slew to the BAT
position until 05:03 UT on 2021 September 30. There will thus be no XRT
or UVOT data for this trigger before this time. 

Due to a discrepancy between the on-board and ground analysis with
the limited data available, we cannot definitively determine
whether this is an astrophysical event.  Further analysis will
be done after the ground telemetry pass. 

Burst Advocate for this burst is B. Sbarufatti (bxs60 AT psu.edu). 
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/)