GCN Circular 6739
Subject
GRB 070809: Keck Imaging
Event
Date
2007-08-10T11:11:05Z (18 years ago)
From
Daniel Perley at U.C. Berkeley <dperley@astro.berkeley.edu>
D. A. Perley (UC Berkeley), C. C. Thoene (DARK, UCB), J. Cooke (UC
Irvine), J. S. Bloom (UCB), and E. Barton (UCI) report:
Starting at 06:21:52 UT (2007-08-10), we imaged the field of GRB 070809
(GCN 6728), a short or intermediate-duration (GCN 6732) burst, with the
Keck I telescope (+LRIS). We obtained under very high airmass (>2.6)
and intervening cirrus 4x300 seconds of imaging in R band and 4x330
seconds in g band.
At the edge of the refined XRT error circle (GCN 6737) we detect a
single, faint source in both filters, with coordinates:
RA = 13:35:04.55
dec = -22:08:30.8
(err: 0.4")
Relative to the USNO B1.0 star at 13:35:09.80 -22:09:15.9 (R2=19.55) we
measure a preliminary magnitude of R~24.0. It is not possible to tell
whether the object is fading, but it does not appear visibly extended.
We note also the presence of an edge-on galaxy near the error circle, at
coordiates of 13:35:04.25, -22:08:26.8.
No other objects are present in or near the error circle to a limiting
magnitude of R~25.5.
An image of the field is available at
http://lyra.berkeley.edu/~dperley/070809/070809keckR.png .