GCN Circular 7696
D. A. Kann, C. Hoegner, and S. Ertel (TLS Tautenburg) report: We observed the afterglow of Swift GRB 080506 (Baumgartner et al., GCN 7685) with the Tautenburg 1.34m Schmidt telescope 1.33 days after the GRB, again in good conditions. We obtained a four 300 sec exposures in the Rc band before twilight shut us down. The afterglow is faintly detected in the stacked image. Using the same comparison star as Kann et al. (GCN 7688), we find: time (days) Rc dRc 1.3346 22.23 0.33 An extrapolation of the decay in the first 0.4 days (~0.63, Kann et al., GCN 7688, de Ugarte Postigo et al., GCN 7690) yields an expected magnitude of Rc ~ 21.8 at 1.33 days after the GRB. Our measured value lies below the extrapolation, indicating a break (possibly a jet break) may have occured. We caution that the detection is rather marginal and the high sky background may falsify the measurement. This message may be cited.