GRB 060211

C. Hurkett (U Leicester), A. Beardmore (U. Leicester), O. Godet (U. Leicester),
J. A. Kennea (PSU), H. Krimm (GSFC/USRA), F. Marshall (GSFC),
J. Osborne (U. Leicester), D. Palmer (LANL), A. Parsons (GSFC)
on behalf of the Swift Team:

At 09:39:11 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 060211 (trigger=181126).   The BAT on-board calculated
location is RA,Dec 58.402d, +21.486d {03h 53m 36s, +21d 29' 09"} (J2000)
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty).  Since this was a 128 second image trigger,
we cannot determine the nature of the light curve from the TDRSS light curve.
We will be able to comment on the time structure when we receive the
full data set in a few hours.  The Swift spacecraft slewed promptly onto the
BAT position.

The XRT began observing the field at 09:42:07 UT, 177 seconds after the
BAT trigger. XRT found a bright, fading, uncatalogued X-ray source
located at RA(J2000) = 03h 53m 32.5s, Dec(J2000) = +21d 29' 19.3", with
an estimated uncertainty of 5.0 arcseconds (90% confidence radius).
This location is 55 arcseconds from the BAT on-board position, within
the BAT error circle. The initial flux in the 2.5s image was
6.7e-09 erg/cm2/s (0.2-10 keV).

UVOT took a finding chart exposure of 200 seconds with the V filter starting
183 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 0.6 magnitudes.

W. Rujopakarn (U Mich), E.S. Rykoff (U Mich), B. E. Schaefer (Louisiana 
State), F. Yuan (U Mich), S.A. Yost (U Mich), report on behalf of the 
ROTSE collaboration:

ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded 
to GRB 060211 (Hurkett et al., GCN 4736
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 ), producing images beginning 
6.2 s after the GCN notice time. An automated response took the first 
image at 09:41:38.2 UT, 147.2 s after the burst, under twilight 
conditions. We took 10 5-sec, and 100 20-sec exposures. These 
unfiltered images are calibrated relative to USNO A2.0 (R).

Comparison to the DSS (second epoch) reveals no new sources within the 
3-sigma error circle, for both single images and coadding into sets of 
10. Individual images have limiting magnitudes ranging from 14.0-16.2; 
we set the following specific limits.

start UT       end UT      t_exp(s)   mlim   t_start-tGRB(s)  Coadd?
--------------------------------------------------------------------
09:41:38.2   09:41:43.2         5     14.3          147.2       N
09:41:38.2   09:43:51.7       133     15.7          147.2       Y
09:44:00.9   09:48:44.2       283     16.1          289.9       Y

A. Gomboc, C. Guidorzi, I. A. Steele, S. Kobayashi, C.G. Mundell, A.
Monfardini, A. Melandri,
C.J. Mottram, R.J. Smith, D. Bersier,
D. Carter, M.F. Bode (Liverpool JMU), P. O'Brien, E. Rol, N. Bannister
(U. of Leicester) report:

"The 2-m Faulkes Telescope North robotically followed up GRB060211
(SWIFT trigger 181126, Hurkett et al. GCN 4736
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 ) starting 5.4 min after
the GRB trigger time.
Within the XRT position, we do not find an optical counterpart to a 
limiting magnitude of R~18.5 in 3x10s co-added images. In addition, we 
find no obvious candidates in a 4.6' x 4.6' region centered on the 
BAT position, to the same limiting magnitude.
Limiting magnitude has been derived with reference to USNOB1."