TITLE: GCN CIRCULAR NUMBER: 7433 SUBJECT: GRB080319B Liverpool Telescope optical afterglow candidate DATE: 08/03/19 08:25:53 GMT FROM: James Smith at ARI,Liverpool John Moors U R.J. Smith (Liverpool JMU), A. Gomboc (U. Ljubljana), N. Tanvir (Leicester) A. Melandri, C.G. Mundell, I.A. Steele, S. Kobayashi, D. Bersier (Liverpool JMU) report: The 2-m Liverpool Telescope (La Palma) observed the position of GRB 080319B (SWIFT trigger 306757) starting 30 min after the GRB trigger time. We detect an optical afterglow candidate in r' filter at 14:31:41 +36:18:09 J2000 consistent with the uncatalogued source visible in the UVOT data. Filter t_mid (min from GRB) Tot_Exp (s) R -------------------------------------------------------------- r' 30.64 120 14.9 r' 32.83 120 15.1 r' 35.02 120 15.2 ------------------------------------------------------------- Observations were performed in SDSS r' filter and magnitudes calibrated vs R2 USNO-B1 magnitudes for a few selected stars. No further observations were possible due to approaching twilight.