[vsnet-grb-info 13424] GRB 130603B: VLT/X-shooter redshift confirmation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14757
SUBJECT: GRB 130603B: VLT/X-shooter redshift confirmation
DATE:    13/06/04 10:38:37 GMT
FROM:    Dong Xu at DARK/NBI  <dong.dark at gmail.com>

D. Xu (DARK/NBI), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D.
Malesani (DARK/NBI), S. Schulze (PUC and MCSS), J. P. U. Fynbo, D. J.
Watson (DARK/NBI), V. D'Elia (ASI-SDC, INAF OAR), P. Goldoni (APC,
CEA/Irfu), M. Vestergaard (DARK/NBI) report on behalf of the X-shooter
GRB GTO collaboration:

We observed the optical afterglow of the short-duration GRB 130603B
(Melandri et al., GCN 14735; Levan et al., GCN 14742; de Ugarte
Postigo et al., GCN 14743) using the ESO VLT equipped with the
X-shooter spectrograph. The observations started on 2013-06-04 at
00:00:28 UT (i.e., 8.187 hr after the burst). A total exposure of
4x600 s was obtained, covering the spectral range from ~300 to ~2100
nm.

A continuum is detected in all the UVB/VIS/NIR arms of the spectra. We
identify several absorption features which we interpret as Ca II H & K
and Mg II from the optical afterglow, as well as emission lines such
as the [O II] doublet, [O III], H-alpha, H-beta, and [S II] from the
host galaxy, all at a common redshift of z=0.3564+/-0.0002, fully
consistent with the measurements by Thoene et al. (GCN 14744), Foley
et al. (GCN 14745), and Sanchez-Ramirez et al. (GCN 14747).

We thank the Paranal staff for enthusiastic support, in particular
Cedric Ledoux and Alex Correa.