TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2036 SUBJECT: GRB 030328, optical photometry DATE: 03/03/31 00:49:49 GMT FROM: Peter Garnavich at U of Notre Dame P. Garnavich (Notre Dame), P. Martini (OCIW), and K.Z. Stanek (CfA) We imaged the optical afterglow of GRB 030328 (Peterson & Price, GCN 1974) with the Magellan 6.5-m Clay telescope and LDSS2 imaging/spectrograph on March 30.04 (1.57 days after the burst). The 2x180 sec R-band images provide a magnitude estimate of 21.93 +\- 0.06 assuming star "B" (GCN 1977) is R=16.10. Using the Magellan photometry from March 29 (Martini et al. GCN 1979), we find a powerlaw decay index of -1.3 +/- 0.1. Our R-band magnitude estimate 1.57 days after the burst is close to that predicted by Price & Peterson (GCN 1977) based on early photometry and a decay index of -1.0. This message may be cited.