TITLE:   GCN CIRCULAR
NUMBER:  14621
SUBJECT: GRB 130511A: Gemini-North Redshift
DATE:    13/05/11 13:17:16 GMT
FROM:    Antonino Cucchiara at UCSC/UCO Lick  <acucchia@ucolick.org>

A. Cucchiara (UCSC) and N. R. Tanvir (U. Leicester) 
report on behalf of a larger collaboration:

On May 11.511 UT (~45 minutes after the Swift trigger)
we observed the optical counterpart of GRB 130511A
(Krimm et al. GCN 14620) with the GMOS spectrograph
mounted on the Gemini-North telescope.

The observation consists of 2x900s exposures
using the B600 grating and covers the 5100-7900
Angstroms wavelength range.

The resulting spectrum presents several absorption lines, 
including FeII(2344,2382,2374,2600), FeII*(2338,2349), 
FeI2463, MnII(25762594), MgII doublet (2796,2803A), and 
MgI2853 at the common redshift of z=1.3033.

We therefore propose this as the redshift of GRB 130511A.

We thank the Gemini staff for performing this
observation, in particular Tom Geballe.