[vsnet-grb-info 4723] GRB 070529: Gemini Redshift

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6470
SUBJECT: GRB 070529: Gemini Redshift
DATE:    07/05/29 20:55:06 GMT
FROM:    Edo Berger at Carnegie Obs  <eberger at ociw.edu>

E. Berger (Carnegie), D. B. Fox and A. Cucchiara (Penn State) report:

"Starting on 2007 May 29.59 UT we used GMOS on the Gemini North telescope 
to obtain a 900 sec spectrum of the afterglow of GRB 050729 (GCN 6466). 
The spectrum covers the wavelength range 5000-7900A.  We find several 
strong absorption features corresponding to CIV, SiII, FeII, AlII, AlIII, 
etc. at a redshift of z=2.4996, which we identify as the redshift of the 
burst.  At this redshift the observed fluence of 2.6e-6 erg/cm^2 (GCN 
6468) translates to an isotropic equivalent energy of 3.8e52 erg."