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GCN Circular 33136

GRB 221231A: AKO Upper Limit
2023-01-01T17:47:10Z (a year ago)
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


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.
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