GCN Circular 17199
C. Guidorzi (U. Ferrara), A. Gomboc (U. Ljubljana) on behalf of a larger collaboration report: The 2-m Liverpool Telescope automatically began observing Swift GRB 141220A (Cummings et al. GCN 17196) on Dec 20 at 06:04:57 UT (125 sec after the burst trigger). The robotic LT-TRAP pipeline identified the optical afterglow at the position reported by Gorosabel et al. (GCN 17197) with r=18.6 +- 0.1 mag at 34 minutes after the GRB, calibrated against nearby SDSS-R stars.