TITLE: GCN CIRCULAR NUMBER: 6322 SUBJECT: GRB 070419: Keck/LRIS Absorption Redshift DATE: 07/04/19 21:54:28 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko, S. Gezari, T. Small (Caltech), D. B. Fox (Penn State), and E. Berger (Carnegie) report on behalf of a larger collaboration: We have obtained a spectrum of the optical afterglow of GRB070419A (Chornock et al., GCN 6304) with the Low-Resolution Imaging Spectrometer mounted on the 10-m Keck I telescope. Observations consisted of 2 x 900 s spectra taken at a mean epoch of approximately 11:36 19 April UT (~ 1.62 hr after the burst). We identify a single strong absorption system, including Mg II, Fe II, Mn II, and Fe I features, at a preliminary redshift of z = 0.97. Coupled with the lack of Lyman-alpha absorption down to ~ 3500 A, we consider this system is likely from the host galaxy of GRB070419A.