TITLE: GCN CIRCULAR NUMBER: 31862 SUBJECT: GRB 220408A: LCO Optical Afterglow Detection DATE: 22/04/09 10:15:46 GMT FROM: Robert Strausbaugh at U. of the Virgin Islands R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (College of Marin) report on behalf of a larger collaboration: We observed Swift (Caputo et al. GCN 31848) and Fermi (Fermi GBM team, GCN 31847) GRB220408A with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site, on April 9, from 06:30 to 06:57 UT (corresponding to 0.63 to 1.18 hours from the GRB trigger time) with the Bessel R and I filters. We performed a series of 3x300s exposures in I and R bands. We detect an optical counterpart within the XRT enhanced error region (Beardmore et al., GCN 31852) in both bands, consistent with other optical detections (Caputo et al. GCNC 31848, Zheng et al. GCNC 31850, Oates et al. GCNC 31855). The following magnitudes are calculated using the USNO-B.1 catalog as reference: R=21.66+/-0.17 I=19.63+/-0.11 These magnitudes are not corrected for galactic extinction. R.S. is funded by NSF AST grant #1831682