GCN Circular 5866
D. A. Kann (TLS Tautenburg) and D. Malesani (NBI/Dark) report: We are observing the afterglow of GRB 061126 (Sbarufatti et al., GCN 5854, Vanden Berk et al., GCN 5856) with the 1.34m Schmidt telescope of the Thueringer Landessternwarte Tautenburg in Germany. Sky conditions are variable, with passing clouds. Observations started at 18:20:41 UT and consist of 600 s R band exposures. The initial airmass was 1.47, it is decreasing. The afterglow is detected on most single frames. From a raw image, we measure the following magnitude in comparison to the USNO-B1 catalog (R1 magnitudes): R = 21.5 +/- 0.25 at 0.49907 days after the burst. (Errors are 0.2 mag statistical and 0.1 mag systematic.) We find this agrees very well with an alpha = 1 extrapolation of the data of Smith et al. (GCN 5857) and Updike et al. (GCN 5959). Observations are continuing as weather permits. Spectroscopy is encouraged. This message may be cited.