TITLE: GCN CIRCULAR NUMBER: 41985 SUBJECT: GRB 250925A: Swift detection of a burst DATE: 25/09/25 17:19:22 GMT FROM: David Palmer at LANL <palmer@lanl.gov> S. Dichiara (PSU), R. Gupta (NASA GSFC), N. J. Klingler (GSFC/UMBC/CRESSTII), S. Lanava (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 17:04:26 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 250925A (trigger=1352124). Swift could not immediately slew to the burst due to an observing constraint. The BAT on-board calculated location is RA, Dec 341.201, +46.574 which is RA(J2000) = 22h 44m 48s Dec(J2000) = +46d 34' 25" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve is only available until T+8s, but this shows a complex peak of at least 20 s duration. The peak count rate was ~1400 counts/sec (15-350 keV), at ~1 sec after the trigger. Due to an observing constraint, Swift will not slew at this time. XRT and UVOT data will be obtained later. Burst Advocate for this burst is S. Dichiara (sbd5667 AT psu.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/41985. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...