TITLE: GCN CIRCULAR NUMBER: 14366 SUBJECT: GRB 130408A - Gemini-S/GMOS redshift determination DATE: 13/04/09 01:47:25 GMT FROM: Nial Tanvir at U.Leicester N. R. Tanvir (U. Leicester), A. Cucchiara (UCSC/UCO Lick Observatory) and S. B. Cenko (UC Berkeley) report on behalf of a larger collaboration: We observed the afterglow of GRB 130408A (Lien et al. GCN 14361, Melandri et al. GCN 14362, Siegel et al. GCN 14363) with the GMOS-S spectrograph on Gemini-S, beginning approximately 1 hr 56 mins after the BAT trigger. The integration was 4x600s and the wavelength covered approximately 3950-6700A. We detect numerous lines, including Lyman alpha, beta, gamma, SII1250, SII1253, CII/CII*1260, SiII*1264, OI1302, SiII/OI*1304, SiII*1309, CII/CII* 1334/1335, SiIV1394/1402 at a common redshift of z=3.757. We thank D. Krogsrud for performing the observation.