GCN Circular 4629
Subject
GRB 060202: Swift detection of a burst
Date
2006-02-02T09:33:04Z (19 years ago)
From
Scott Barthelmy at NASA/GSFC <Scott@lheamail.gsfc.nasa.gov>
D. Fox (PSU), S. Barthelmy (GSFC), D. Burrows (PSU), J. Cummings (GSFC/NRC),
N. Gehrels (GSFC), S.T. Holland (GSFC/USRA), S. Hunsberger (PSU),
H. Krimm (GSFC/USRA), D. Morris (PSU), D. Palmer (LANL)
on behalf of the Swift team:
At 08:40:55 UT, Swift-BAT triggered and located GRB 060202 (trigger=179968).
The spacecraft slewed immediately. The BAT on-board calculated location
is RA,Dec 35.843d,+38.362d {02h 23m 22s,+38d 21' 43"} (J2000),
with an uncertainty of 3 arcmin (radius, 90% containment, stat+sys).
This was a 64-sec image trigger. The BAT light curve shows a broad and
weak peak with a total duration of >20 sec. The peak count rate was
~500 counts/sec (15-350 keV), at ~5 seconds after the trigger.
XRT began observing the GRB at 08:43:18 UT, 143.3s after the BAT trigger.
A bright, uncatalogued, fading source, was found by the on-board
centroiding algorithm at
RA(J2000)=02h 23m 23.1s
DEC(J2000)=+38d 23' 09.2"
with an uncertainty of 6 arcseconds radius (90% containment).
This position lies 87 arcseconds from the center of the BAT error
circle. The XRT count rate clearly decreases as a power law
in the first 100s. The initial XRT flux was ~2.5E-8 ergs/cm2/s.
UVOT took a finding chart exposure of 200 seconds with the V filter
starting 148 seconds after the BAT trigger. No 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 18th 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 of about 0.2 magnitudes.