TITLE: GCN CIRCULAR NUMBER: 16493 SUBJECT: GRB 140629A: TNG redshift confirmation DATE: 14/06/30 10:04:17 GMT FROM: Paolo D'Avanzo at INAF-OAB P. D'Avanzo (INAF-OAB), D. Malesani (DARK/NBI), V. D'Elia, L.A. Antonelli (INAF/OAR & ASI/ASDC), G. Tagliaferri (INAF-OAB), S.D. Vergani (CNRS/GEPI), A. Fiorenzano, G. Mainella (INAF/TNG) report on behalf of the CIBO collaboration: We observed the optical afterglow of GRB 140629A (Lien et al., GCN 16477; Yurkov et al. GCN 16478) on 2014 June 30 with the 3.6m TNG telescope located in the Canary Islands, equipped with the DOLORES operated in both imaging and spectroscopic mode. The observations were carried out under poor weather conditions (clouds and calima). In a 120 s image started at 01:41:38 UT (~11.4 hr after the GRB), the afterglow has a magnitude r = 20.4 +/- 0.1 (AB), calibrated against nearby SDSS stars. We also obtained three optical spectra, each one lasting 1200 s, using the grism LR-B covering the wavelength range 3000 - 8000 AA. The observation started at 02:07:21 UT (~11.8 hr after the GRB). Using a preliminary wavelength calibration, in the co-added spectrum we detect several absorption lines which we interpret as due to Ly-alpha, C II (1334), C IV (1548/1550) at a common redshift of 2.29. Our result is in agreement with the redshift reported by Moskvitin et al. (GCN 16489).