TITLE: GCN CIRCULAR NUMBER: 14804 SUBJECT: GRB 130606A: P60 Observations DATE: 13/06/07 11:48:56 GMT FROM: Daniel Perley at Caltech D. A. Perley (Caltech) and S. B. Cenko (GSFC) report on behalf of a larger collaboration: We imaged the field of GRB 130606A (Ukwatta et al., GCN 14781) with the robotic Palomar 60-inch telescope throughout the night of 2013-06-07 UT, beginning at 04:01 UT and continuing until morning twilight at 11:39 UT. Initial observations consisted of a series of r, i, and z-band frames; later in the night we switched to exclusively z-band observations. Transparency and seeing conditions were good throughout. The GRB afterglow (Jelinek et al., GCN 14782; Xu et al., GCN 14783; Nagayama et al., GCN 14784) is well-detected in the z-band exposures and marginally detected in the other filters. Preliminary (not fringe-corrected) aperture photometry of a few select points yields: t_start(d) t_exp(s) filter magnitude 0.30679 180 z = 18.62 +/- 0.08 0.42224 180 z = 19.22 +/- 0.09 0.50888 180 z = 19.59 +/- 0.11 0.58040 180 z = 19.73 +/- 0.22 The afterglow decays as a power-law with an index of approximately alpha=1.6-1.7 over the course of the observations. Given the redshift (Castro-Tirado et al., GCN 14796; Lunnan et al., GCN 14798) these relatively bright fluxes indicate an extremely luminous afterglow, especially at early times; similar to the luminous high-redshift GRB 050904 (e.g. Kann, Masetti, & Klose 2007; AJ 133:1187).