[vsnet-grb-info 6176] GRB 080604: Hobby-Eberly Telescope spectroscopy

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  7805
SUBJECT: GRB 080604: Hobby-Eberly Telescope spectroscopy
DATE:    08/06/04 11:39:53 GMT
FROM:    Antonino Cucchiara at PSU  <cucchiara at astro.psu.edu>

A. Cucchiara and D. B. Fox (Penn State) report:

"Starting on 2008 June 4.35 UT we used the Marcario LRS spectrograph
on the Hobby-Eberly Telescope (R ~ 230) to obtain a 1200s spectrum
of the optical afterglow of GRB 080604 (La Parola et al., GCN 7800).
The spectrum covers the wavelength range 4500 to 10,000 Angstrom.
Based on a preliminary calibration we detect absorption features
corresponding to the MgII doublet (2796, 2803 A) and MgI (2852 A)
as well as other metal absorption features at redshift z = 1.28.

The absence of Lyman break in our dataset suggests z < 2.7.

A refined analysis will be posted.

We thank the HET staff for performing this observation,
in particular Matthew Shetrone."