GCN Circular 4867

C. Pagani (PSU), S. Barthelmy (GSFC), J. Cummings (GSFC/ORAU), N. Gehrels (GSFC),
D. Grupe (PSU), S.T. Holland (GSFC/USRA), S. Hunsberger (PSU),
C. Markwardt (GSFC/UMD), F. Marshall (GSFC), D. Palmer (LANL)
on behalf of the Swift team:

At 00:12:06 UT, Swift-BAT triggered and located GRB 060313 (trigger=201487).
The spacecraft slewed immediately.  The BAT on-board calculated location is
RA,Dec 66.609d,-10.872d {04h 26m 26s,-10d 52' 19"} (J2000), with an uncertainty
of 3 arcmin (radius, 90% containment, stat+sys).  The BAT light curve shows
two slightly overlapping peaks with a total duration of ~1.6 sec.
The first peak start at ~T-0.7 sec and the second peak ends by T+0.9 sec.
The peak count rate was ~40,000 counts/sec (15-350 keV), at ~0.0 seconds
after the trigger.  This is definitely a short hard burst.

The XRT began taking data at 00:13:24 UT, 79 seconds after the BAT trigger.
The XRT on-board centroid algorithm did not find a source in the image and
no prompt position is available.  We are waiting for down-linked data
to detect and determine a position for the source.

UVOT took a finding chart exposure of 200 seconds with the V filter starting
78 seconds after the BAT trigger.  No afterglow candidate has been found
in the initial data products.  The 2.7'x2.7' sub-image covers 25% of the
BAT error circle.  The typical 3-sigma upper limit has been about 18th mag.
The 8'x8' region for the list of sources generated on-board covers 100%
of the BAT error circle.  The list of sources is typically complete to
about 18.0 mag.  No correction has been made for the expected extinction
of about 0.2 magnitudes.

We note that the magnitude B=16.3 galaxy LEDA 3093309 (aka  NPM1G -10.0175)
is within 5 arcminutes of the BAT position, however there is currently
no evidence for a physical association between these two objects.