TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2041 SUBJECT: GRB 030329, optical photometry DATE: 03/03/31 05:22:25 GMT FROM: Peter Garnavich at U of Notre Dame K.Z. Stanek (CfA), P. Martini (OCIW) and P. Garnavich (Notre Dame) Images of the GRB 030329 afterglow (Peterson & Price: GCN 1985; Torii: GCN 1986) were obtained with the Magellan 6.5-m Clay telescope beginning March 31.068 (UT). Four 30-sec exposures were taken in the R-band with the LDSS2 imaging/spectrograph. Using the calibration by Henden (GCN 2023) for "star A" (GCN 2012) at 10:44:42 +21:32:31 (2000) of R=16.06, we find the brightness of the afterglow is R=16.21 +/- 0.05. This is nearly a magnitude brighter than expected from the extrapolation of a powerlaw decay slope of -1.9 found around 16 hours after the burst by Garnavich, Stanek & Berlind (GCN 2018), Smith (GCN 2019) and Halpern et al. (GCN 2021). Apparently, a more shallow decay has reappeared as reported by Lipkin et al. (GCN 2034). We combined the Clay images, taken in 1" seeing, and subtracted the afterglow point-spread function but no evidence of the host galaxy was detected. This message may be cited.