TITLE: GCN CIRCULAR NUMBER: 41911 SUBJECT: GRB250920C: LCOGT Optical Detection DATE: 25/09/20 17:10:36 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 250920C field (Gupta et al., GCN 41904) with the LCOGT 1-meter Sinistro instrument at the Siding Spring Observatory, Australia site, on September 20, from 16:29 to 16:51 UT (corresponding to 1.07 to 1.26 hours after the GRB trigger time) with the SDSS r and i filters. We performed a series of 3x200s exposures in i-band and r-band. We detect an uncatalogued source consistent with GOTO optical counterpart candidate (Wortley et al., GCN 41907) in both bands. The following magnitudes are calculated using the PanSTARRS catalog as reference: r = 18.54 +/- 0.05 i = 18.25 +/- 0.01 These magnitudes are not corrected for galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/41911. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...