TITLE: GCN CIRCULAR NUMBER: 33136 SUBJECT: GRB 221231A: AKO Upper Limit DATE: 23/01/01 17:47:10 GMT FROM: Mohammad Odeh at Al Khatim Observatory M44 Mohammad Odeh of Al-Khatim Observatory (AKO) operated by the International Astronomical Center, in Abu Dhabi, UAE. As a follow up for the GRB 221231A detected by Fermi/GBM (GCN 33129) and the observations of the Swift/BAT-GUANO (Perri et al., GCN 33135), we observed the localization of the five detected uncatalogued X-ray sources mentioned in GCN 33135. Our observation was done with our 0.36m f/7.7 robotic telescope on 01 January 2023 around 15:27 (UT), 17.7 hours after the GRB trigger. We obtained multiple 180-sec exposures in Ic filter. We did not detect any afterglow within the mentioned locations. The following upper limit was calculated using Atlas catalogue as a reference: ---------------------------------------------------------------------------- - JD (mid), T_mid-T0(hrs), Exposure (sec), Filter, Lim_mag ---------------------------------------------------------------------------- - 2459946.143993, 17.7, 5 x 180 (stacked), Ic, > 18.8 ---------------------------------------------------------------------------- - These magnitudes are not corrected for galactic extinction.