GCN Circular 9266
Subject
GRB 090426: Okayama MITSuME optical observation
Date
2009-04-26T23:13:33Z (15 years ago)
From
Michitoshi Yoshida at Okayama Astrophysical Obs <yoshida@oao.nao.ac.jp>
M. Yoshida, D. Kuroda, K. Yanagisawa, Y. Shimizu, S. Nagayama,
H. Toda (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf
of the MITSuME collaboration:
We detected the optical afterglow of GRB 090426 (Cummings et al.
GCN 9254; Xin et al. GCN 9255; Oates et al. GCN 9265) with the
optical three color (g', Rc and Ic) CCD camera attached to the
MITSuME 50cm telescope of Okayama Astrophysical Observatory.
The observation started on 2009-04-26 12:49:50 UT (63 sec after
the alert). We found the afterglow at the UVOT position of the
GRB (Oates et al. GCN 9265) in all the three bands. It rapidly
faded from 1 min to 2 hours from the burst.
Photometric results listed below. We used GSC2.3 catalog for
flux calibration. We did not apply Galactic extinction to the
following results.
#PDAY MID-UT T-EXP g' g'_err Rc Rc_err Ic Ic_err
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0.00108 12:50:20 60.0 17.21 0.15 16.54 0.09 15.95 0.11
0.00436 12:55:04 540.0 17.81 0.08 17.30 0.08 16.90 0.10
0.01198 13:06:03 540.0 19.43 0.31 19.16 0.27 18.30 0.26
0.01116 13:04:52 1500.0 18.58 0.12 18.04 0.09 17.61 0.11
0.06343 14:20:08 3000.0 20.42 0.38 19.86 0.22 19.46 0.35
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