GCN Circular 5568
Subject
GRB 060912: Redshift of nearby 2MASS galaxy
Date
2006-09-13T06:56:08Z (18 years ago)
From
Edo Berger at Carnegie Obs <eberger@ociw.edu>
E. Berger (Carnegie Observatories) reports on behalf of a larger
collaboration:
"Starting on 2006 Sep. 13.22 UT we used GMOS on Gemini-South to obtain an
1800 sec spectrum of the bright 2MASS galaxy located 11" away from the
optical afterglow position of GRB 060912 (GCN 5558), at a position angle
that also included the afterglow position. The spectrum of the 2MASS
galaxy it typical of an early-type galaxy with CaII H&K, Mg b, and Na D
absorption features at a redshift, z=0.0936. At the position of the
afterglow we do not detect any clear continuum emission or emission lines
(4000-7000 A). If the 2MASS galaxy is in fact the host galaxy of GRB
060912, then the isotropic-equivalent gamma-ray energy is only 2.6e49 erg.
Moreover, the nature of the host galaxy would suggest that the GRB is most
likely to be a short burst. Deep imaging observations to search for a
faint galaxy at the position of the afterglow are planned."