Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 6739

GRB 070809: Keck Imaging
2007-08-10T11:11:05Z (17 years ago)
Daniel Perley at U.C. Berkeley <>
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 .
Looking for U.S. government information and services? Visit