TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3948 SUBJECT: GRB 050908: spectroscopic redshift DATE: 05/09/08 09:30:59 GMT FROM: Daniele Malesani at SISSA-ISAS,Trieste,Italy D. Fugazza (INAF/OABr), F. Fiore (INAF/OARm), F. Patat, C. Ledoux (ESO), P. D'Avanzo (INAF/OABr), L.A. Antonelli (INAF/OARm), G. Chincarini (INAF/OABr & Univ. Milano-Bicocca), D. Malesani (SISSA/ISAS), S. Covino, G. Tagliaferri (INAF/OABr), S. Piranomonte and L. Stella (INAF/OArm), report on behalf of the MISTICI collaboration: We observed the optical afterglow (Torii, GCN 3943; Cenko, Fox & Berger, GCN 3944) of GRB 050908 (Goad et al., GCNs 3942, 3946) with the ESO-VLT UT2, equipped with the FORS1 instrument. Spectroscopy was performed with the grism 300V, covering the wavelength range 4500-8500 AA. Twenty minutes of exposure were acquired starting on 2005 Sep 8, 07:19 UT. Data reduction was performed using archivial calibration files, so that small systematic uncertainties may be present in our analysis. Based on the detection of Lyalpha, SiIV1309,1402, CIV1548,1550, SiII1206, and the Lyman limit, we measure a redshift z = 3.350 +- 0.005. Further analysis is in progress and results will be communicated later. We acknowledge the outstanding support received from the ESO staff. This message can be cited. [GCN OPS NOTE(10sep05): Per author's request, "N. Patat" was changed to "F. Patat".]