GCN Circular 8713
Subject
GRB 081222: Gemini-South absorption redshift
Date
2008-12-23T14:58:35Z (16 years ago)
From
Antonino Cucchiara at PSU <cucchiara@astro.psu.edu>
A. Cucchiara, D. B. Fox (Penn State), S. B. Cenko (Berkeley) and E. Berger
(Harvard) report on behalf of a larger collaboration:
Starting at 01:02 UT on 2008 December 23 we observed the optical
counterpart of GRB 081222 (Grupe et al., GCN 8691, Covino et al.,
GCN 8692 and Updike et al. 8693) using Gemini-South with the GMOS-South
spectrograph (R~1600).
We acquired 2x900s spectra covering the wavelength range 4000A-8000A.
We detect a damped Lyman-alpha system (DLA) at redshift z=2.77.
We also detect several metal absorption features which we interpret as
SiIV(1393,1402), SiII1526 and 1260, SiII*1264, CII1334, CII*1335,
CIV(1548,1550), FeII1608 and NiII(1454) at the same redshift.
In combination with the strong metal absorption features, the detection of
a DLA at z = 2.77 confirms that this is the redshift of GRB 081222 and its
host galaxy.
We thank the Gemini staff, in particular Henry Lee, for conducting
these observations.