GCN Circular 12761
Subject
GRB 111228A: Gemini South Redshift
Date
2011-12-29T08:25:14Z (12 years ago)
From
Antonino Cucchiara at LBNL <acucchiara@lbl.gov>
A. Cucchiara (UCSC/UCO Lick), A. J. Levan (U. Warwick),
and S. B. Cenko (UC Berkeley) report:
We obtained spectroscopy of the optical afterglow of
GRB 111228A (Ukwatta et al., GCN 12737) using GMOS-South
on the Gemini-South 8-m telescope.
Observations began on December 29.28 UT (15 hrs after the
BAT trigger).
Inspection of the first two exposures (range 4160-8140 Angstroms)
reveals MgII2796,2803, MgII2853 and CaH&K absorption features
at a common redshift of 0.716.
We therefore suggest this to be the redshift of GRB 111228A.
We thank the Gemini staff for performing this observation,
in particular Pascale Hibon.