TITLE: GCN CIRCULAR NUMBER: 38012 SUBJECT: GRB 241030B: LCOGT Optical Upper Limits DATE: 24/10/31 14:09:14 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 Fermi/Swift GRB 241030B field (Fermi GBM Team, GCN 37980; Klingler et al., GCN 37981) with the LCOGT 1-meter Sinistro instrument at the Teide Observatory, Tenerife site, on October 30, from 21:50 to 22:22 UT (corresponding to 3.27 to 3.8 hours after the GRB trigger time) with the sdss r and i filters. We performed a series of 3x300s exposures in i- and r-bands. We do not detect a source within the enhanced Swfit XRT error region (Evans et al., GCN 37983) in either band. This result is consistent with fading from early optical detections (Fu et al., GCN 37985; Odeh et al, GCN 37986; Moskvitin et al., GCN 37987, Brivio et al., GCN 37991; Moskvitin et al., GCN 37995; Qiu et al., GCN 37999; Tanvir et al., GCN 38004; Breeveld et al., GCN 38008) and other optical upper limits (Klotz et al., GCN 37989; Hagio et al., GCN 38001). The following 5-sigma upper limits are calculated using the PanSTARRS catalog as reference: r > 22.5 i > 22.0 These magnitudes are not corrected for galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/38012. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...