TITLE: GCN CIRCULAR NUMBER: 15964 SUBJECT: GRB 140311A: NOT redshift confirmation DATE: 14/03/12 13:37:59 GMT FROM: Valerio D'Elia at ASDC P. D'Avanzo (INAF-OAB), V. D'Elia (INAF-OAR/ASI-ASDC), S. Piranomonte (INAF-OAR), A. Melandri (INAF-OAB), D. Malesani (DARK/NBI), T. Pursimo (NOT), M. C. Baglio, I. Andreoni (INAF-OAB) report on behalf of the CIBO collaboration: Following the detection of the optical afterglow reported in D'Avanzo et al. (GCN 15953), we carried out optical spectroscopy of GRB 140311A (Racusin et al. GCN 15944) with the Nordic Optical Telescope (NOT) equipped with ALFOSC. The observation consisted of two 1800 s exposures covering the range between 3200 and 9100 A carried out at a mean t-t0=3.37 hours. Despite the low SNR and a seeing of ~2, we detect broad absorption features at lambda ~ 7300 and 6100 AA which we interpret as Ly-alpha and Ly-beta at z ~ 5. This is consistent with the redshift reported by Tanvir et al(GCN 15961). ---------------------------------------------------------------- This message was sent using IMP, the Internet Messaging Program.