GCN Circular 16514
Subject
GRB 140703A: P60 observations of a red, slowly-fading afterglow
Date
2014-07-03T16:51:02Z (10 years ago)
From
Daniel Perley at Caltech <dperley@astro.caltech.edu>
D. A. Perley (Caltech) and S. B. Cenko (NASA/GSFC) report:
We observed the afterglow of GRB 140703A (Kocevski et al., GCN 16503)
with the Palomar 60-inch (P60) robotic telescope. We acquired 3x180s in
each of the r, i, and z filters between 08:40:37 and 09:11:02 on
2014-07-03 UT. We measure the following magnitudes:
r = 20.03 +/- 0.02 t_mid = 0.3462 days
i = 19.46 +/- 0.02 t_mid = 0.3380 days
z = 18.99 +/- 0.05 t_mid = 0.3533 days
This indicates very little fading since the observations of Cunniffe et
al. (GCN 16504) and Ciabattari et al. (GCN 16511). However, the
spectroscopy of Castro-Tirado et al. (GCN 16505) confirms this source is
the GRB afterglow.
We note that the afterglow color is fairly red (beta~2.2 after
correction for foreground extinction), possibly indicating significant
dust obscuration in the host frame.