TITLE: GCN GRB OBSERVATION REPORT NUMBER: 604 SUBJECT: GRB 000301C, Optical Observation DATE: 00/03/10 02:52:21 GMT FROM: Jules Halpern at Columbia U. J. P. Halpern & J. Kemp (Columbia U.) report on behalf of the MDM Observatory GRB follow-up team: "We reobserved GRB 000301C in the R band on March 9.52 UT using the MDM 1.3m telescope, measuring R = 22.28 +/- 0.09 referenced to the comparison stars of Garnavich et al. (GCN #573). Seeing was 1."4. If we restrict our attention to those GCN reported magnitudes that have error bars less than or equal to 0.1 mag, then the light curve is reasonably well described by a power-law decay of alpha = -0.90 +/- 0.04 until 4 days after the burst, followed by a power-law decay of alpha = -1.93 +/- 0.12. An updated decay curve and a new CCD image are posted at http://www.astro.bio2.edu/grb/000301Ca This message may be cited."