TITLE:   GCN CIRCULAR
NUMBER:  17822
SUBJECT: GRB 150514A: VLT/X-shooter redshift
DATE:    15/05/16 01:30:16 GMT
FROM:    Antonio de Ugarte Postigo at IAA-CSIC  <deugarte@iaa.es>

A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D. Xu (NAOC/CAS), 
D. Malesani (DARK/NBI), N. R. Tanvir (U. Leicester) report on behalf of 
the X-shooter GRB collaboration:

We observed the optical afterglow of GRB 150514A (Kocevski et al. 
GCN 17816, Kennea et al. GCN 17818, Roberts et al. GCN 17819, 
Marshall et al. GCN 17820, Yates et al. GCN 17821) with X-shooter 
at the Very Large Telescope (Paranal Observatory, Chile). Observations 
started at 23:04 UT on 15 May 2015 (28.4 hr after the burst) and 
consisted of 4 x 600 s exposures covering the range between 3000 and 
24800 AA.

The afterglow is well detected in the acquisition image at R(Vega) = 
19.5 mag, calibrated with two nearby USNO B1 stars. The spectrum 
shows a clear continuum over the entire range and absorptions of FeII, 
MgII and MgI at a common redshift of 0.807, which we consider to be 
the redshift of the GRB.

We acknowledge the excellent support provided by Paranal staff, and in
particular John Pritchard and Dimitri Gadotti.