[vsnet-grb-info 14783] GRB 140412A: Swift detection of a burst

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16097
SUBJECT: GRB 140412A: Swift detection of a burst
DATE:    14/04/12 22:33:10 GMT
FROM:    David Burrows at PSU/Swift  <burrows at astro.psu.edu>

V. D'Elia (ASDC), D. N. Burrows (PSU), S. T. Holland (STScI),
L. Izzo (URoma/ICRA), F. E. Marshall (NASA/GSFC), T. Sakamoto (AGU)
and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:

At 22:20:49 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 140412A (trigger=595608).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 145.050, -65.809 which is 
   RA(J2000) = 09h 40m 12s
   Dec(J2000) = -65d 48' 31"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a FRED-like 
structure with a duration of about 20 sec.  The peak count rate
was ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger. 

The XRT began observing the field at 22:24:17.0 UT, 207.2 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 144.9713, -65.8226
which is equivalent to:
   RA(J2000)  = 09h 39m 53.11s
   Dec(J2000) = -65d 49' 21.3"
with an uncertainty of 3.2 arcseconds (radius, 90% containment). This
location is 125 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. No spectrum from the promptly downlinked
event data is yet available to determine the column density. 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 236 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 none of
the XRT error circle. 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 mag. No correction has been made for the expected
extinction corresponding to E(B-V) of 0.22. 

Burst Advocate for this burst is V. D'Elia (delia AT asdc.asi.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.)