TITLE:   GCN CIRCULAR
NUMBER:  35343
SUBJECT: GRB 231215A: Swift detection of a burst
DATE:    23/12/15 09:55:59 GMT
FROM:    David Palmer at LANL <palmer@lanl.gov>


P. D'Avanzo (INAF-OAB), R. Brivio (INAF-OAB), M. Ferro (INAF-OAB),
J.D. Gropp (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL),
T. Sakamoto (AGU), C. Salvaggio (INAF-OAB), T. Sbarrato (INAF-OAB),
B. Sbarufatti (INAF-OAB) and M. H. Siegel (PSU) report on behalf of
the Neil Gehrels Swift Observatory Team:

At 09:47:25 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 231215A (trigger=1202522).  Swift could not immediately slew
due to an Earth limb observing constraint. 
The BAT on-board calculated location is 
RA, Dec 9.750, +57.642 which is 
   RA(J2000) = 00h 39m 00s
   Dec(J2000) = +57d 38' 32"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a complex
structure with a duration of about 30 sec.  The peak count rate
was ~6000 counts/sec (15-350 keV), at ~1 sec after the trigger. 

Due to an observing constraint, Swift will not slew until T0+42.6
minutes. There will be no XRT or UVOT data until this time. 

Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT inaf.it). 
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/)