TITLE: GCN GRB OBSERVATION REPORT NUMBER: 881 SUBJECT: GRB001109, R-band optical observations DATE: 00/11/10 06:38:23 GMT FROM: Krzysztof Z. Stanek at CfA K. Z. Stanek (CfA), P. Garnavich (Notre Dame), K. L. Luhman and B. A. McLeod (CfA) report: We imaged the WFC error box (GCN 879) of GRB001109 with the FLWO 1.2m telescope and R-band filter starting on 2000 Nov. 10.087 (UT). We obtained 2x600-sec R-band exposures. Near the position of the radio source reported by Taylor et al. (GCN 880) we detect faint optical source, R~21.0, located at RA=18:30:06.63, DEC=55:18:34.95 (2000.0). The magnitude estimate for this source was obtained by comparing to USNO star ``A'' at RA=18:30:06.38, DEC=55:19:05.8 (2000.0), R=19.0. This faint optical source near the position of the radio source is also marginally visible at the POSS-II red plate, and thus most likely is not an optical counterpart to GRB001109. Within the WFC error box we do not see any ``new'' sources brighter than R~20.5. Our composite 1200-sec R-band image is available at http://cfa-www.harvard.edu/cfa/oir/Research/GRB/, along with the POSS-II finding chart with positions of the sources marked. This message can be cited.