GCN Circular 10952

V. D'Elia (ASDC), N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU),
E. A. Hoversten (PSU), K. L. Page (U Leicester) and M. H. Siegel (PSU)
report on behalf of the Swift Team:

Swift began a target of opportunity observation of GRB100713A on July
13, 2010 at 16:30 UT, approximately 1.9 hours after the burst was
detected by INTEGRAL. Swift data for these observations utilize Target
ID 20143. 

The XRT began observing the field at 16:20:34.3 UT, 6.2 ks after the
INTEGRAL trigger. Using promptly downlinked data we find an
uncatalogued X-ray source located at RA, Dec 255.20192, 28.39489 which
is equivalent to:
   RA(J2000)  = 17h 00m 48.46s
   Dec(J2000) = +28d 23' 41.6"
with an uncertainty of 4.9 arcseconds (radius, 90% containment). This
location is 29 arcseconds from the INTEGRAL position, within the
INTEGRAL 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. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (5.01e+20
cm^-2, Kalberla et al. 2005), with an excess column of 7.2
(+8.61/-6.14) x 10^21 cm^-2 (90% confidence). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 6246 seconds after the INTEGRAL 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 19.6 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 mag. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.06. 

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.)