GCN Circular 7023
Subject
GRB 071031: VLT high-resolution spectroscopy
Date
2007-10-31T03:19:47Z (17 years ago)
From
Daniele Malesani at Niels Bohr Inst,Dark Cosmology Center <malesani@astro.ku.dk>
C. Ledoux (ESO), P. Jakobsson (Univ. Herfordshire), A.O. Jaunsen (Univ.
Oslo), C.C. Thoene, P.M. Vreeswijk, D. Malesani, J.P.U. Fynbo, J. Hjorth
(DARK), report on behalf of a larger collaboration:
We observed the optical afterglow of GRB 071031 (Stroh et al., GCN 7020;
Kruehler et al., GCN 7021; Haislip et al., GCN 7022) with the ESO VLT.
Observations were triggered automatically in rapid response mode
starting on 2007 Oct 31 at 01:16 UT (9.3 min after the trigger). We
secured high- and low-resolution spectroscopy with UVES and FORS2,
respectively.
From the detection of a DLA and several metallic lines, including
fine-structure transitions, we determine the redshift to be z=2.692,
consistently in the UVES and FORS2 spectra. Further analysis is ongoing.
We acknowledge excellent support from the observing staff at Paranal, in
particular Stan Stefl and Rachel Gilmour.