TITLE: GCN CIRCULAR NUMBER: 7392 SUBJECT: GRB080310, detection of break in optical DATE: 08/03/10 11:05:03 GMT FROM: Peter Garnavich at U of Notre Dame J. L. Prieto (OSU), P. Garnavich (Notre Dame), R. Pogge (OSU) report: We continue to observe the afterglow of GRB 080310 (Garnavich et al., GCN 7390) with the LBT and LBC blue/red cameras. Data taken between 1.7 and 2.1 hours after the burst show a steepening decay rate. The power-law decay index over this period was 1.01 suggesting a break in the light curve is underway. This message may be cited.