TITLE: GCN CIRCULAR NUMBER: 18942 SUBJECT: GRB 160123A: TAROT La Silla observatory optical observations DATE: 16/01/27 15:38:47 GMT FROM: Alain Klotz at IRAP-CNRS-OMP Klotz A., Turpin D. (IRAP-CNRS-OMP), Boer M., Gendre B., Bardho O. (UNS-CNRS-OCA), Gendre B. (Etelman Observatory-UVI), Atteia J.L. (IRAP-CNRS-OMP) report: We imaged the field of GRB 160123A detected by SWIFT (trigger 671447) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile. The observations started 33.1s after the GRB trigger (14.2s after the notice). The elevation of the field decreased from 59 degrees above horizon and weather conditions were good. The first image is trailed with a duration of 60.0s (see the description in Klotz et al., 2006, A&A 451, L39). We do not detect any OT with a limiting magnitude of: t0+33.1s to t0+93.1s : R > 17.3 The second image is 30.0s exposure in tracking mode: t0+108.7s to t0+138.7s : R > 18.1 We co-added a series of exposures: t0+108.7s to t0+305.4s : R > 18.8 Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction.