TITLE: GCN CIRCULAR NUMBER: 12052 SUBJECT: GRB 110530A: optical observations at Mt. Terskol DATE: 11/05/30 21:51:28 GMT FROM: Alexei Pozanenko at IKI, Moscow M. Andreev, A. Sergeev, I. Sokolov (Terskol Branch of Institute of Astronomy), Yu. Bronich (IC AMER of NASU), A.Pozanenko (IKI) on behalf of larger GRB follow up collaboration report: We observed the optical afterglow of the Swift GRB 110530A (D'Avanzo et al, GCN 12046) with Zeiss-2000 and Zeiss-600 telescopes of Mt.Terskol observatory. Optical afterglow is detected in a stacked images. The photometry is based on the star USNO-B1.0 1519-0265568 (RA=18 48 15.86, Dec=+61 56 15.0) assuming R=16.08 is following UT (mid time), Exposure, Filter, OT 18:00 12 x 30 s R(gunn) 20.32 +/- 0.08 18:58 24 x 150 s R 20.6 +/- 0.2