TITLE:   GCN CIRCULAR
NUMBER:  21420
SUBJECT: GRB 170807A: Swift detection of a burst
DATE:    17/08/07 22:08:20 GMT
FROM:    David Palmer at LANL  <palmer@lanl.gov>

J.D. Gropp (PSU), S. D. Barthelmy (GSFC), D. M. Palmer (LANL),
B. Sbarufatti (INAF-OAB/PSU) and A. Tohuvavohu (PSU) report on behalf
of the Swift Team:

At 21:56:09 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 170807A (trigger=766821).  Swift could not slew to the 
burst due to a Sun constraint.  The BAT on-board calculated location is 
RA, Dec 143.379, -17.329 which is 
   RA(J2000) = 09h 33m 31s
   Dec(J2000) = -17d 19' 44"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed two FRED
structures with a total duration of about 40 sec.  The peak count rate
was ~2500 counts/sec (15-350 keV), at ~1 sec after the trigger. 

Due to a Sun observing constraint, Swift cannot slew to the BAT
position until 06:56 UT on 2017 October 03. There will thus be no XRT
or UVOT data for this trigger before this time. 

Burst Advocate for this burst is J.D. Gropp (jdg44 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/too.html.)