TITLE: GCN CIRCULAR NUMBER: 31572 SUBJECT: GRB 220210A: Swift/BAT-GUANO localization DATE: 22/02/11 04:27:48 GMT FROM: Aaron Tohuvavohu at U Toronto Aaron Tohuvavohu (U Toronto), James DeLaunay (UAlabama), Gayathri Raman (PSU), Jamie A. Kennea (PSU), report: Swift/BAT did not localize GRB 220210A onboard (T0: 2022-02-10T23:56:38 UTC, Fermi/GBM GCN 31568, CALET trig 1328572556). The Fermi and CALET notices, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). Upon trigger, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. The GRB is clearly detected in the BAT data, with a duration of ~15 seconds. A location for the burst is found with conventional BAT imaging, with SNR 11.4. While the derived location is precise to ~2 arcminute with respect to the spacecraft pointing, the conversion to celestial coordinates is complicated by the current operational mode of Swift (GCN 31500, 31547). The BAT position is RA, Dec = 345.778, +61.826 deg which is RA(J2000) = 23h 03m 6.9s Dec(J2000) = +61d 49′ 33.2″ with an estimated uncertainty of 2 arcmin with respect to the spacecraft pointing. The uncertainty in the Swift attitude in the current mode is believed to be ~1-2 degrees (M. Ajello et al, 2008 ApJ 689, 666). The position is consistent with the Fermi/GBM localization (GCN 31568). NITRATES results are not yet available, and will be reported in a future circular. There will be no XRT/UVOT followup (GCN 31547). We encourage followup from other instruments. GUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches.