TITLE: GCN CIRCULAR NUMBER: 41781 SUBJECT: GRB 250911A: Swift detection of a burst DATE: 25/09/11 01:43:39 GMT FROM: David Palmer at LANL <palmer@lanl.gov> N. J. Klingler (GSFC/UMBC/CRESSTII), S. Dichiara (PSU), R. Gupta (NASA GSFC), A. Y. Lien (U Tampa) and D. M. Palmer (LANL) report on behalf of the Neil Gehrels Swift Observatory Team: At 01:27:46 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 250911A (trigger=1348587). Due to an observing constraint Swift did not immediately slew to the burst. The BAT on-board calculated location is RA, Dec 263.762, -16.844 which is RA(J2000) = 17h 35m 03s Dec(J2000) = -16d 50' 36" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure with a duration of about 20 sec. The peak count rate was ~1200 counts/sec (15-350 keV), at ~3 sec after the trigger. Due to an observing constraint, Swift will not slew until T0+50 minutes. There will be no XRT or UVOT data until this time. Burst Advocate for this burst is N. J. Klingler (noelklin AT umbc.edu). 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/) View this GCN Circular online at https://gcn.nasa.gov/circulars/41781. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...