GCN Circular 17584
D. A. Perley (Caltech) and S. B. Cenko (NASA/GSFC) report: The Palomar 60-inch robotic telescope began automatic follow-up of the location of GRB 150314A (Hagen et al., GCN 17573) at 05:08:40 UT on 2015-03-14, 13.4 minutes after the GRB trigger. A sequence of 60-second r, i, and z exposures were acquired, lasting until 06:36 UT. Another sequence of 180-second g, r, and i exposures was taken between 09:01 UT and 10:54 UT. We detect the optical afterglow reported by Zheng and Filippenko (GCN 17574) in individual exposures from the early sequence as well as in a stack of the later-time exposures. Calibrating to a nearby USNO star (RA=126.701423, dec=63.829609, R2=15.33) gives the following photometry: t_med = 834s : R = 18.59 +/- 0.05 t_med = 1179s : R = 18.96 +/- 0.05 t_med = 1437s : R = 19.06 +/- 0.07 t_med = 1693s : R = 19.41 +/- 0.07 t_med = 1977s : R = 19.59 +/- 0.08 t_med = 18365s : R = 21.73 +/- 0.13 The afterglow fades as approximately t^-0.9 throughout our observations.