TITLE:   GCN CIRCULAR
NUMBER:  20257
SUBJECT: GRB 161214B: Swift detection of a burst
DATE:    16/12/14 17:32:35 GMT
FROM:    David Burrows at PSU/Swift  <burrows@astro.psu.edu>

P. D'Avanzo (INAF-OAB), D. N. Burrows (PSU), J. A. Kennea (PSU),
H. A. Krimm (CRESST/NSF/USRA), N. P. M. Kuin (UCL-MSSL),
A. Y. Lien (GSFC/UMBC), A. Melandri (INAF-OAB),
K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU)
report on behalf of the Swift Team:

At 17:20:10 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 161214B (trigger=726885).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 3.850, +7.342 which is 
   RA(J2000) = 00h 15m 24s
   Dec(J2000) = +07d 20' 31"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single FRED-shaped
structure with a duration of about 20 sec.  The peak count rate
was ~2900 counts/sec (15-350 keV), at ~1 sec after the trigger. 

The XRT began observing the field at 17:21:25.5 UT, 74.9 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 3.85151, 7.35291 which is
equivalent to:
   RA(J2000)  = 00h 15m 24.36s
   Dec(J2000) = +07d 21' 10.5"
with an uncertainty of 4.2 arcseconds (radius, 90% containment). This
location is 39 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper.  We
cannot determine whether the source is fading at the present time. No
spectrum from the promptly downlinked event data is yet available to
determine the column density. 

The initial flux in the 2.5 s image was 1.29e-09 erg cm^-2 s^-1 (0.2-10
keV). 

UVOT data are unavailable at this time. 

Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT brera.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/too.html.)