TITLE: GCN CIRCULAR NUMBER: 10090 SUBJECT: GRB 091020: Late TLS detection DATE: 09/10/27 02:31:21 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann, U. Laux, M. Roeder & H. Meusinger (TLS Tautenburg) report: We observed again the afterglow of the Swift GRB 091020 (Racusin et al., GCN 10048) with the 1.34m Schmidt telescope of the Thueringer Landessternwarte Tautenburg, Germany, on the 26th of October, 5.2 days after the GRB. We obtained 11 x 600 sec images in Rc before clouds shut us down again. At the position of the afterglow, we detect a faint source in the stacked image. We derive the following afterglow magnitudes using the same comparison star as Kann et al., GCN 10076: dt Filter mag dmag ____________________________________ 5.213357 Rc 23.62 0.31 Kann et al., GCN 10076, found a single power-law decay with alpha = 1.12 +/- 0.06. Compared to the extrapolation of this fit, there is no significant evidence for a break yet. No further observations are possible due to an instrument change. This message may be cited.