[vsnet-grb-info 12123] GRB 120724A: Gemini-N tentative redshift

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13512
SUBJECT: GRB 120724A: Gemini-N tentative redshift
DATE:    12/07/24 09:51:40 GMT
FROM:    Antonino Cucchiara at UCSC/UCO Lick  <acucchia at ucolick.org>

A. Cucchiara (UCSC/UCO Lick), N.R. Tanvir (U. Leicester), 
D. Perley (Caltech), and A. J. Levan (U. Warwick) report 
on behalf of a larger collaboration:

We observed the afterglow of GRB 120724A (Guidorzi et al. 
GCN 13511; D'Avanzo et al. GCN 13510) using the GMOS-N 
spectrograph on the Gemini-North telescope under very good 
seeing conditions (0.5").

Observations began at 2012-7-24 08:31 UT, about 2 hr post-burst.
Two spectra of 900s each were acquired, covering the
6000-10000 Angstrom wavelength range.

A preliminary analysis of some of the absorption features
identified suggests that the GRB redshift is z = 1.48, 
based on identification of MgII2796,2803 doublet, 
MnII2606, FeII2600, and MnII2594.

We thank the Gemini staff, in particular J. Holt and 
J. Kemp, for making these observations possible.