[vsnet-grb-info 20948] GRB 180728A: Swift detection of a bright burst

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23046
SUBJECT: GRB 180728A: Swift detection of a bright burst
DATE:    18/07/28 17:38:09 GMT
FROM:    David Palmer at LANL  <palmer at lanl.gov>

R. L. C. Starling (U Leicester), S. D. Barthelmy (GSFC),
A. Y. Lien (GSFC/UMBC), M. J. Moss (George Washington University),
K. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 17:29:00 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 180728A (trigger=850471).  Swift did not slew immediately
due to the Earth limb constraint.  The BAT on-board calculated location is 
RA, Dec 253.569, -54.031 which is 
   RA(J2000) = 16h 54m 17s
   Dec(J2000) = -54d 01' 50"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a small precursor
followed 10 seconds later by a bright FRED pulse of ~20 s duration. 
The peak count rate was ~100,000 counts/sec (15-350 keV), at ~13 sec 
after the trigger. 

Due to an observing constraint, Swift will not slew until T0+23.6
minutes. There will be no XRT or UVOT data until this time. 

Burst Advocate for this burst is R. L. C. Starling (rlcs1 AT star.le.ac.uk). 
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.)