GCN Circular 8889
Subject
GRB 090205: VLT spectroscopic redshift
Date
2009-02-06T08:57:35Z (15 years ago)
From
Paolo D'Avanzo at INAF-OAB <paolo.davanzo@brera.inaf.it>
C. C. Thoene, D. Fugazza, P. D'Avanzo (INAF-OAB), V. D'Elia, S.
Piranomonte (INAF-OAR), R. Salvaterra, S. Covino, S. Campana (INAF-OAB),
G. Chincarini (Univ. Bicocca) report, on behalf of the MISTICI
collaboration:
We observed the optical afterglow of GRB 090205 (D'Avanzo et al. GCN
8887; Kruehler & Greiner GCN 8888) with the ESO VLT about 9.0 hours
after the burst with the FORS1 camera in spectroscopic mode. We took a
20 min spectrum covering the range 4000-9000 Angstrom (based on a
preliminary wavelength calibration) with a resolution of R=440.
We detect a broad absorption feature around lambda_obs = 6800 Angstrom.
Interpreting this feature as Ly-alpha absorption the inferred redshift
is z = 4.6 in agreement with the photometric redshift reported by
Kruehler & Greiner (GCN 8888).
We acknowledge excellent support from the ESO staff, in particular G.
James and J. Smoker.