TITLE: GCN CIRCULAR NUMBER: 14878 SUBJECT: GRB 130612A: NOT optical observations DATE: 13/06/12 04:50:12 GMT FROM: Dong Xu at DARK/NBI P. Jakobsson (U. Iceland), D. Xu (DARK/NBI), D. Malesani (DARK/NBI), K. Mikkelsen (U. Oslo), N. Aghanim (CNRS & Universite Paris-Sud Orsay) report on behalf of a larger collaboration: We observed the optical afterglow of GRB 130612A (Racusin et al., GCN 14874; Melandri et al., GCN 14875) using the 2.5-m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. We obtained 4x300s R-band images with a median time 04:06:09 UT on 12 June 2013 (i.e. 0.73 hr after the burst). The optical afterglow was clearly detected with R ~ 20.3 mag calibrated with nearby stars in the USNO B1 catalog. [GCN OPS NOTE(12jun13): Per author's request, NA was added to the author list.]