GCN Circular 12759
Subject
GRB 111228A: MMT Redshift
Date
2011-12-29T08:16:27Z (12 years ago)
From
Edo Berger at Harvard <eberger@cfa.harvard.edu>
J. Dittman, T. Laskar, and E. Berger (Harvard) report:
"Starting on 2011 December 29.312 UT (15.7 hours after the burst) we
used the Blue Channel spectrograph mounted on the MMT 6.5-m telescope
to observe GRB111228A (GCN #12737). Our spectra cover the range
3400-8500A and reveal absorption lines of MgII and FeII at a common
redshift of z=0.714, which we consider to be the redshift of
GRB111228A. Additional observations are in progress."