GCN Circular 8993
Subject
GRB 090313 optical observations
Event
Date
2009-03-14T01:47:12Z (17 years ago)
From
AAVSO GRB Network at AAVSO <matthewt@aavso.org>
Markku Nissinen (Varkaus, Finland) reports to the AAVSO High Energy Network
the following optical observations of GRB 090313 (Chornock, Li, and
Filippenko, GCN #8979; Mao et al., GCN #8980):
Markku Nissinen reports the detection of the optical counterpart of GRB
090313 using the GRAS-04 telescope sited in Mayhill, NM, USA. A number
of unfiltered observations with varying exposure times were made using
the 0.25-meter telescope with an SBIG ST8XE CCD camera; observations began
approximately 1 hour post burst. The afterglow was detected in all frames
with astrometric positions matching those given by Chornock, Li, and
Filippenko (GCN #8979) and Updike et al (GCN #8983) to within positional
errors.
The following unfiltered magnitudes were obtained from the observations
using USNO-A2.0 U0975_07146255 (R magnitude = 15.9) as the comparison:
obs midpoint(UT) exptime mag(CR) mag.err
2009-03-13 10:14:41 360 sec 16.5 +/- 0.3 (3 x 120 sec)
2009-03-13 10:27:59 300 sec 16.7 +/- 0.3
2009-03-13 10:39:53 600 sec 16.9 +/- 0.3
A FITS image of the 300-second observation is available at the following URL:
ftp://ftp.aavso.org/grb/MarkkuNissinen_GRB090313_2454904.28608_.fits
The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network.