N. R. Tanvir (U. Leicester), K. E. Heintz (U. Iceland, DARK/NBI),
J. Selsing (DARK/NBI), J. Japelj (API, U. Amsterdam),
J. Bolmer (ESO/MPE), D. A. Kann (HETH/IAA-CSIC), D. Xu (NAOC),
A. de Ugarte Postigo (HETH/IAA-CSIC and DARK/NBI),
D. Malesani (DARK/NBI), J. P. U. Fynbo (NBI), G. Pugliese (API, U. Amsterdam)
report on behalf of the STARGATE Consortium:
We observed the bright optical counterpart of the Swift
GRB 180205A (Evans et al. GCN 22381; Zheng et al. GCN 22382;
Bolmer et al. GCN 22383) with the ESO Very Large Telescope UT 2 (Kueyen)
equipped with the X-shooter spectrograph, covering the wavelength
range 3500-24000 AA. Observations started on February 05.25 UT
(approx 1.5 hr after the GRB) and consisted of 4 exposures of
600 s each.
The spectrum exhibits many absorption features including
C II, Si II, Si II*, Al II, Fe II, Mg II, Mg I at a common redshift of
z=1.409. We conclude this is the redshift of the GRB.
We acknowledge the expert support from the ESO observing
staff, in particular Jesus Corral-Santana and Cedric Ledoux.