GCN Circular 6450
Subject
GRB070521: Gemini Observations
Event
Date
2007-05-22T03:13:53Z (19 years ago)
From
S. Bradley Cenko at Caltech <cenko@srl.caltech.edu>
S. B. Cenko (Caltech), P. A. Price (IfA/Hawaii), and E. Berger (OCIW)
report on behalf of a larger collaboration:
We have imaged the field of GRB070521 (Guidorzi et al.; GCN 6431) with the
Gemini Multi-Object Spectrograph (GMOS) and the Near-Infrared Imager
(NIRI) mounted on the Gemini North Telescope. Observations were taken in
the g', i', z' (GMOS) and J, H, Ks (NIRI) filters, beginning at 7:36:54
UT on 21 May 2007.
We weakly detect the host candidate proposed by Hattori, Aoki, and Kawai
(GCN 6444) only in our i'- and Ks-band images. In the table below we
report a summary of our observations. Photometric calibration was
performed relative to SDSS (Cool et al.; GCN 6432) for the GMOS images
and the 2MASS point source catalog for our NIRI imaging.
Filter t - t_b (hr) Exposure (s) Magnitude
-------------------------------------------------------------------------
g' 1.08 2 x 180 > 25.0
i' 1.21 2 x 180 ~ 24.1
z' 1.33 4 x 180 > 23.0
J 1.92 15 x 30 > 21.5
H 2.20 15 x 30 > 21.0
Ks 2.50 15 x 30 ~ 22.3