GCN Circular 4808
E. Berger (Carnegie), B. P. Schmidt (ANU), and A. M. Soderberg (Caltech) report on behalf of a larger collaboration: "As part of our spectroscopic observations with GMOS on Gemini-south (GCN 4804) we obtained a single 30-sec r-band image of the field on 2006, Feb 21.01 UT. Calibration against 9 nearby stars from SDSS (GCN 4777) yields r = 17.92+/-0.12 mag for the afterglow+SN+host. Subtracting off the contribution of the host (r = 19.93+/-0.03; GCN 4777) we find that the afterglow+SN faded by 0.43+/-0.22 mag compared to the measurement by Mirabal (GCN 4784). This corresponds to a decay rate of -0.4+/-0.2, which is relatively shallow compared to typical optical afterglows, and furthermore indicates a turnover in the flux evolution following the initial period of brightening in the B,V bands observed with UVOT (GCN 4800)."