TITLE: GCN CIRCULAR NUMBER: 35278 SUBJECT: GRB 231205B: LCOGT Optical Upper Limits DATE: 23/12/06 04:03:52 GMT FROM: Robert Strausbaugh at Eastern Illinois University <rstrausbaugh@eiu.edu> R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration: We observed the Swift GRB 231205B field (Evans et al., GCN 35269) with the LCOGT 1-meter Sinistro instrument at the McDonald Observatory, USA site, on December 6, from 01:40 to 02:12 UT (corresponding to 8.95 to 9.48 hours from the GRB trigger time) with the SDSS r and i filters. We performed a series of 3x300s exposures in each band. We do not detect a source within the Swift-XRT error region around the enhanced XRT position (Osborne et al., GCN 35275) in either band, consistent with other non-detections (Odeh et al., GCN 35270) The following 5-sigma upper limits are calculated using the PanSTARRS catalog as reference: r > 22.6 i > 21.9 These magnitudes are not corrected for galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/35278. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...