GCN Circular 10156
Subject
GRB 091109B: VLT afterglow confirmation
Date
2009-11-10T10:00:29Z (14 years ago)
From
Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst <malesani@astro.ku.dk>
D. Malesani (DARK/NBI), A. de Ugarte Postigo (INAF/OABr), A. J. Levan
(Univ. Warwick), N. R. Tanvir (Univ. Leicester), J. Hjorth (DARK/NBI),
P. D'Avanzo (INAF/Brera), report on behalf of a larger collaboration:
Following the observations of GRB 091109B (Oates et al., GCN 10148) with
the VLT reported by Levan et al. (GCN 10154), we obtained a further
epoch of R-band imaging with mean time Nov 10.33 UT (10.22 hr after the
burst), using the same instrument and configuration.
Source "A" by Levan et al. (GCN 10154) is still detected, and decayed by
1.0+-0.3 mag during this time interval, implying a decay index of alpha
= 1.7+-0.5. We hence conclude that the source is indeed the afterglow of
GRB 091109B.
We acknowledge excellent support from the ESO staff at Paranal, in
particular Alain Smette and Paul Lynam.