TITLE:   GCN CIRCULAR
NUMBER:  3201
SUBJECT: GRB 050408: Emission and absorption redshift
DATE:    05/04/09 07:17:46 GMT
FROM:    Edo Berger at Carnegie Obs  <eberger@ociw.edu>

Edo Berger, Mike Gladders, and Gus Oemler (Carnegie Observatories) report:

"On 2005, April 9.22 UT we obtained a spectrum of the optical afterglow
(GCN 3193) of GRB 050408 (GCN 3189) with LDSS-3 on the Magellan/Clay
telescope.  We find a broad emission line which we interpret as [OII]3727
at a redshift of z=1.236 and an absorption doublet which we interpret as
MgII 2796/2803 at the same redshift.

Given a fluence of about 3.3e-6 erg/cm^2 the isotropic-equivalent
gamma-ray energy is 1.3e52 erg."