TITLE: GCN CIRCULAR NUMBER: 28669 SUBJECT: Trigger 1000631: Swift detection of Cen X-3 DATE: 20/10/17 13:49:49 GMT FROM: Boris Sbarufatti at PSU V. D'Elia (SSDC) and B. Sbarufatti (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 13:13:50 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 201017B (trigger=1000631). Swift did not slew to the source. The BAT on-board calculated location is RA, Dec 170.233, -60.614 which is RA(J2000) = 11h 20m 56s Dec(J2000) = -60d 36' 48" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a double-peaked structure. The peak count rate was ~1265 counts/sec (15-350 keV), at ~6 sec after the trigger.