GCN Circular 13628
Subject
GRB 120811C: Redshift from OSIRIS/GTC
Event
Date
2012-08-11T23:14:09Z (13 years ago)
From
Antonio de Ugarte Postigo at IAA-CSIC <deugarte@iaa.es>
C. C. Thoene (IAA-CSIC), A. de Ugarte Postigo (IAA-CSIC, DARK),
J. Gorosabel, R. Sanchez-Ramirez (IAA-CSIC) and
J. P. U. Fynbo (DARK) G. Gomez Velarde (GTC) report
on behalf of a larger collaboration:
We observed the afterglow of GRB 120811C (Barlow et al.,
GCN 13622) with OSIRIS at the 10.4m GTC telescope starting at
UT 22:07 (6.5 hr after the burst) for a total exposure time of 2400s.
We used grism 1000B covering the wavelength range between
3700 and 7800 Angstrom.
Despite Calima, the continuum is clearly detected and the
spectrum shows strong Ly alpha and Ly beta absorption as well
as a number of absorption lines (SII, SiII, OI, CII, CIV, SiIV, AlII,
AlIII, NiII, ZnII and SiII*) at a common redshift of z=2.671.