GCN Circular 23686

M. H. Siegel (PSU), D. N. Burrows (PSU), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. J. Klingler (PSU), H. A. Krimm (NSF/USRA),
N. P. M. Kuin (UCL-MSSL), S. J. LaPorte (PSU), A. Y. Lien (GSFC/UMBC),
M. J. Moss (George Washington University), K. L. Page (U Leicester),
B. Sbarufatti (PSU) and A. Tohuvavohu (PSU) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 19:31:12 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 190114B (trigger=883818).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 174.883, +18.877 which is 
   RA(J2000) = 11h 39m 32s
   Dec(J2000) = +18d 52' 36"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a weak pulse
with a duration of about 20 sec. Also, there is a possible precursor
at ~T-75 s. The peak count rate was ~800 counts/sec (15-350 keV), 
at ~4 sec after the trigger. 

The XRT began observing the field at 19:33:49.6 UT, 157.5 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source located at RA, Dec 174.87349, 18.89230 which
is equivalent to:
   RA(J2000)  = 11h 39m 29.64s
   Dec(J2000) = +18d 53' 32.3"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This
location is 63 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. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 1.75
x 10^20 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 250 seconds with the U filter starting
157 seconds after the BAT trigger. No credible afterglow candidate has been
found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the
XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. The
8'x8' region for the list of sources generated on-board covers 100% of the XRT
error circle. The list of sources is typically complete to about 18.0 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.02. 

Burst Advocate for this burst is M. H. Siegel (siegel AT swift.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.)