TITLE: GCN CIRCULAR NUMBER: 7418 SUBJECT: GRB 080315: Optical observations DATE: 08/03/15 05:28:20 GMT FROM: Antonio Deugarte at IAA-CSIC A. de Ugarte Postigo (ESO, Chile), Virginie Chantry (U. Liege, Belgium), A.J. Castro-Tirado, M. Jelinek, J. Gorosabel (IAA-CSIC, Spain), C. Melo, A. Smette (ESO, Chile) report: We have observed the field of GRB 080315 (Page et al., GCN 7416) with the 1.3m Mercator telescope at La Palma starting at 02:55 UT (30 min after the burst). The observation consisted on a series of 24x60s I-band exposures. The combined exposure, with mean time 3:26 UT (61.3 minutes after the burst), does not show any new source inside the 3 arcmin BAT error box down to a limiting magnitude of I~20.8 (USNO-B1.0 was used as photometric reference) as compared to SDSS i-band frame. This message may be cited.