[vsnet-grb-info 10949] GRB 110918A: Gemini-N redshift

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  12368
SUBJECT: GRB 110918A: Gemini-N redshift
DATE:    11/09/20 15:30:29 GMT
FROM:    Nial Tanvir at U.Leicester  <nrt3 at star.le.ac.uk>

A.J. Levan (U. Warwick), N.R. Tanvir, K. Wiersema (U. Leicester),
E. Berger (Harvard), D. Fox (Penn State) report on behalf of a larger
collaboration:


We observed the candidate optical afterglow of GRB 110918A reported by
Tanvir et al. (GCN12365) with the GMOS-N spectrograph on Gemini-N,
Mauna Kea. Â Observations began at 20-Sep-2011 12:51 UT. Â The trace is
well detected and consistent with being a power-law continuum,
confirming that this source is very likely the afterglow of the burst
detected by the IPN (Hurley et al. GCN12357, see also Cenko et
al. GCN12367). Â We identify absorption features of MgII (2796A/2804A),
MgI (2853A) and CaII (3935A/3970A) at a common redshift of z=0.982 (based
on a provisional wavelength calibration).


We thank the Gemini staff, particularly Jen Holt, for obtaining
these observations.