TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5278 SUBJECT: GRB 060105: Upper limit on Host Galaxy DATE: 06/06/27 18:49:53 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann (Thueringer Landessternwarte Tautenburg) and S. Manohar (USC, Los Angeles), report: We observed the field of GRB 060105 (Ziaeepour et al., GCN 4429) with the Tautenburg 1.34m Schmidt telescope under good observing conditions. We obtained 6 x 600 sec images in the Rc filter for a total integration time of 60 minutes. The mean observation time was June 27.9288 UT, which is 172.7 days after the burst. We determine the zero point of the image in comparison with nine unsaturated and isolated stars of the USNOB1.0 catalog. Astrometry is also performed against the USNOB1.0 catalog. At the refined position of the X-ray afterglow (Godet et al., GCN 4433), we do not detect any sources. The 2 sigma limiting magnitude of the image is Rc=23, but the position of the afterglow is affected by the PSF of several nearby bright stars. We set a limiting magnitude of Rc=22.5 for any source at this position. This magnitude is not corrected for the moderate foreground extinction, E(B-V)=0.171. This message may be cited.