GRB 021204

K. Torii (RIKEN), H. Yamaoka (Kyushu U.), and T. Kato (Kyoto U.)
report:

 Starting at 15:21:26 UT on December 4th, the central 53x53 arcmin of
the error region of GRB 021204 (HETE trigger 2486; GRB time
13:14:46.11 UT) was observed at RIKEN with 0.2-m f/4 reflector
equipped with unfiltered CCD AP7p.

 Visual comparison of the first frame (30-s integration) with DSS does
not show a new object brighter than ~16.5 (USNO-A2.0 red magnitude).

M. Nysewander, D. Reichart (U. North Carolina) and M. Schwartz
(Tenagra Observatories) report:


We imaged 100% of the error box of GRB 021204 with the 32-inch Tenagra II
telescope beginning at 07:58:37 UT on Dec 5 and 08:07:35 UT on Dec 6, 0.7
and 1.7 days after the burst.  For both epochs we integrated in the Ic band
for 600s in eight pointings.  We note that the Galactic extinction along
this line of sight is approximately A_Ic = 0.9 mag (Schlegel et al. 1998).

Using the image subtraction software ISIS2 (Alard 2000), we find no
transient to the limiting magnitude of our first epoch images, which we
estimate to be Ic = 21.3 (3 sigma) using 5 USNO-A2.0 stars.

Alard, C., 2000, A&AS 114, 363
Schlegel, D., et al. 1998, ApJ, 500, 525

M. Ishiguro, Y. Sarugaku, H. Nonaka, S. M. Kwon (ISAS)
S. Nishiura, H. Mito, and Y. Urata on behalf of the Kiso GRB team:

" We observed the central 50 x 50 arcmin of the error region of GRB
021204 (HETE trigger 2486; GRB time 13:14:46.11 UT) with the 105-cm
Schmidt telescope at the Kiso observatory, the University of
Tokyo. Starting at 2002 December 4.812 UT, 300-s exposures were made
in B, V, R, I band.  Comparison with the DPOSS image did not show an
optical afterglow candidate brighter than 18.7R mag."

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