GCN Circular 15144
Subject
GRB 130831A: Gemini-North Redshift
Event
Date
2013-08-31T15:37:32Z (13 years ago)
From
Antonino Cucchiara at UCSC/UCO Lick <acucchia@ucolick.org>
A. Cucchiara (UCSC/UCO Lick Observatory), D. Perley (Caltech)
report on behalf of a larger collaboration:
"We observed the afterglow of GRB 130831A (Hagen et al.
GCN 15139, Guidorzi et al. GCN 15140) with the GMOS spectrograph
on Gemini-North, beginning approximately 50 min after the BAT trigger.
We obtained 2x900s exposure spectra under exquisite conditions
using the B600 grism, covering the 3860-6649 Angstrom wavelength range.
In our preliminary analysis we detect MgII2796,2803 doublet and
MgI2853 absorption lines at z=0.4791.
No other strong features are detected in absorption or in emission,
therefore we suggest this as the redshift of GRB 130831A.
We thank the Gemini-N staff, in particular Adam Smith and
Anthony Matulonis, for their support."