GCN Circular 16181
D. A. Perley (Caltech) reports: I re-observed the afterglow candidate of GRB 140428A in longslit mode using LRIS on the Keck I 10m telescope. One 940-second exposure was taken using the 400/8500 grating (red camera) and 600/4000 grism (blue camera). In a provisional reduction, the spectrum of the object shows a weak, flat continuum between 7000 Angstroms and the red limit of the wavelength range at approximately 10100 Angstroms. The flux sharply drops to zero at 7000 angstroms, though there is faint flux detected in some places slightly further to the blue. No trace is detected on the blue camera. If the drop at 7000 Angstroms is interpreted as a DLA and the onset of the Lyman-alpha forest, this would indicate a redshift for this object of approximately z=4.7.