TITLE: GCN CIRCULAR NUMBER: 22095 SUBJECT: GRB 171103A: Swift detection of a short hard burst DATE: 17/11/03 23:23:43 GMT FROM: David Palmer at LANL T. N. Ukwatta (LANL), A. D'Ai (INAF-IASFPA), V. D'Elia (ASDC), Alex Deich (PSU), H. A. Krimm (NSF/USRA), N. P. M. Kuin (UCL-MSSL), D. M. Palmer (LANL), M. H. Siegel (PSU) and A. Tohuvavohu (PSU) report on behalf of the Swift Team: At 23:10:32 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 171103A (trigger=785850). Swift did not slew due to an observing constraint. The BAT on-board calculated location is RA, Dec 249.536, -10.215 which is RA(J2000) = 16h 38m 09s Dec(J2000) = -10d 12' 53" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of less than 1 sec. The peak count rate was ~20000 counts/sec (15-350 keV), at ~0 sec after the trigger. Due to a Sun observing constraint, Swift cannot slew to the BAT position until 11:32 UT on 2018 January 15. There will thus be no XRT or UVOT data for this trigger before this time. Burst Advocate for this burst is T. N. Ukwatta (tilan.ukwatta AT gmail.com). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/too.html.)