[vsnet-grb-info 2845] GRB060206: Swift-BAT detection of a burst

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4682
SUBJECT: GRB060206: Swift-BAT detection of a burst
DATE:    06/02/06 05:36:23 GMT
FROM:    David Palmer at LANL  <dmpalmer at mac.com>

D. Morris (PSU), L. Barbier (GSFC), S. Barthelmy (GSFC),
J. Cummings (GSFC/ORAU), N. Gehrels (GSFC), S. Hunsberger (PSU),
C. Markwardt (GSFC/UMd), D. Palmer (LANL), and E. Rol (U. Leicester)
on behalf of the Swift team:

At 04:46:53 UT, Swift-BAT triggered and located GRB060206  
(trigger=180455).
The spacecraft slewed immediately. The BAT on-board location is
RA,Dec 202.946d,+35.075d {13h 31m 47s,+35d 04' 29"} (J2000), with
an uncertainty of 3 arcmin (radius, 90% containment, stat+sys).
The BAT light curve showed a single bright gaussian-peak
structure from T-1 to T+10 sec. The peak count rate was ~6000
counts/sec (15-350 keV), at ~2 seconds after the trigger.

The XRT began taking data at 04:47:52, 58 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. The burst occurred shortly before
entry into the SAA, and therefore the count-rate lightcurve may be
insensitive to a fading source.  We are waiting for down-linked data
to determine a position.

UVOT took a finding chart exposure of 72 seconds with the V filter
starting 58 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 8'x8' region for the list
of sources generated on-board covers 100% of the BAT error circle.
No correction has been made forthe expected extinction of
about 0.04 magnitudes.