GCN Circular 7706
Subject
GRB 080507: Keck photometry
Date
2008-05-10T02:33:56Z (16 years ago)
From
Daniel Perley at U.C. Berkeley <dperley@astro.berkeley.edu>
D. A. Perley (UC Berkeley), J. X. Prochaska (UCO/Lick), and J. Hennawi
(UCB) report:
We imaged the field of Super-AGILE GRB 080507 (Lapshov et al., GCN 7697)
with Keck I (+LRIS) during morning twilight starting at 15:03 UT on
2008-05-08 (31.3 hours after the trigger). Four exposures were taken in
g and R filters simultaneously, although due to twilight only the first
two R-band frames were usable.
We detect the optical afterglow reported by Kann et al. (GCN 7701) at a
position of:
RA = 15:34:43.39
Dec = +56:26:08.28
(estimated uncertainty of 0.7")
in R-band. Our magnitude, calibrated to seven USNO-B1.0 stars, is R =
22.20 +/- 0.11 at 1.31 days after the trigger. This supports the
generally non-fading behavior between 1-2 days after burst in
observations from the Swift UVOT (Breeveld et al., GCN 7702) and
Tautenberg (Kann et al.).
For reference, the observed magnitudes of two nearby USNO stars in the
same calibration system are:
15:35:10.99 +56:23:57.02 R = 20.53 +/- 0.02
15:34:47.68 +56:25:16.44 R = 18.63 +/- 0.01