[vsnet-grb-info 5686] GRB080229: Possible optical afterglow

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  7341
SUBJECT: GRB080229: Possible optical afterglow
DATE:    08/03/01 03:16:54 GMT
FROM:    Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida at oao.nao.ac.jp>

M. Yoshida, K. Yanagisawa, Y. Shimizu, S. Nagayama, H. Toda
 (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf of the
MITSuME collaboration:

We performed optical imaging observations (g', Rc, and Ic) of the
field of GRB 080229 (Cannizzo et al. GCN 7335) with 50cm MITSuME
telescope at Okayama Astrophysical Observatory from UT 17:06:55
(117sec after the trigger) to UT 17:24:40 on Feb 29 2008.

We found a faint fading source in the XRT error circle (Cannizzo
et al: GCN 7335) only in the Ic band. There was no source in the
g' and the Rc bands. Together with the UVOT results (Kuin and
Cannizzo GCN7339), this may suggest that this GRB is a high-
redshift one. Follow-up observations in infrared bands are
encouraged.

The magnitude of the fading source and 3-sigma upper limits are
summarized below.

Observation date  2008-02-29 UT

mid-UT    exp-T      g'      Rc       Ic
---------------------------------------------
17:09:40   5 min   >17.5   >17.8    17.1+-0.3
17:18:58  11 min   >17.6   >18.2    >18.0
---------------------------------------------

The values quoted above are not corrected for the Galactic
extinction.