TITLE: GCN CIRCULAR NUMBER: 6235 SUBJECT: GRB 070330: TAROT La Silla observatory optical observations DATE: 07/03/31 07:22:04 GMT FROM: Alain Klotz at CESR-CNRS Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report: We imaged the field of GRB 070330 detected by SWIFT (trigger 273180) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile. The observations started 2.5 hours after the GRB trigger (the field was not risen when the burst occured). The date of trigger : t0 = 2007-03-30T22:51:30.816 We co-added a series of 180s exposures: We do not detect any OT at the XRT position (Grupe et al. GCNC 6234) with a limiting magnitude of: t0+2.5h to t0+3.5h : R > 17.4 Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction. N.B. Galactic coordinates are lon=329.9005 lat=-18.5620 and the galactic extinction in R band is 2.0 magnitudes estimated from D. Schlegel et al. 1998ApJ...500..525S. This message may be cited.