GCN Circular 7621
Subject
GRB 080319B: Continued Gemini-N monitoring
Date
2008-04-15T22:36:51Z (16 years ago)
From
Nial Tanvir at IofA U.Cambridge <nrt@ast.cam.ac.uk>
N. R. Tanvir (U. Leicester), D. A. Perley (UC Berkeley),
A. J. Levan (U. Warwick), J. S. Bloom (UC Berkeley),
A. S. Fruchter (STScI) and E. Rol (U. Leicester) report:
We obtained a further epoch of observations of GRB 080319B with
Gemini-North/GMOS on April 14 UT. These observations yielded the
following magnitudes: g=25.80+/-0.09, r=24.93+/-0.07, i=24.22+/-0.05.
Although the r-band magnitude is consistent with a continued power-law
decline in flux, the source is now clearly much redder than it was at
early times, suggesting it is likely contaminated by light from a host
galaxy and/or associated supernova. The g-band observation, which
would be less contaminated by any SN light, indicates a steeper
decline which may be consistent with a break in the underlying
afterglow light curve (GCN 7567).
The absence of any extended emission in the previous HST observations
(GCN 7569) argues against a significant host contribution, although a very
compact host is not ruled out.
Further analysis is ongoing.
We thank Gemini staff astronomers, particularly Sandy Leggett, for
their support in obtaining these observations.