GCN Circular 2832
Subject
GRB 041006: GETS Optical Afterglow Observation
Date
2004-11-05T04:25:03Z (20 years ago)
From
Kenzo Kinugasa at Gunma Astro. Obs/Japan <kinugasa@astron.pref.gunma.jp>
K. Kinugasa (Gunma Astronomical Observatory) and K. Torii (Osaka U.)
report:
Starting at 12:50:19 UT on 2004 October 6 (32 minutes after the burst
trigger), the sky area of GRB041006 (Galassi, et al. GCN 2770) was
observed with the GETS (0.25-m robotic telescope equipped with
unfiltered CCD in the Gunma Astronomical Observatory). The observation
continued for 6.5 hours and 30-s exposure frames were obtained.
We stacked 20 original frames into a single frame and find that the
optical afterglow (Da Costa, et al. GCN 2765) is detected in the
stacked frames. Between 12:57 and 14:55 UT (mean epoch), we obtained
10 independent measurements and the afterglow faded from Rc=17.8 to
Rc=18.7 by using a comparison star from Henden's calibration (GCN 2801).
After 15:02 UT, intermittent clouds came to cover the field of view and
the afterglow was not detected.