TITLE: GCN CIRCULAR NUMBER: 2179 SUBJECT: GRB 030329 Oprical observations in Rozhen observatory DATE: 03/04/30 11:30:26 GMT FROM: Evgeni Semkov at Inst.of Astronomy,Bulgaria E. Semkov (Institute of Astronomy, Sofia, Bulgaria) report: We continue our observations of the afterglow of HETE burst (H2652) GRB 030329 (Peterson & Price, GCN 1985; Torii: GCN 1986) with the 2m RCC telescope of the National Astronomical Observatory Rozhen (Bulgaria). We obtained four 300 s exposures on 25 Apr UT 19:30 with Photometrics CCD camera and Rc filter. The observations were carried out under good seeing and atmospheric conditions. Using field photometry of Henden (GCN2082) and after co-adding of frames we estimate the brightness of the optical afterglow as Rc = 20.21 +/-0.09. This message may be cited.