TITLE: GCN CIRCULAR NUMBER: 38699 SUBJECT: GRB 241229B: Swift detection of a burst DATE: 24/12/29 01:52:48 GMT FROM: Amy <yarleen@gmail.com> A. D'Ai (INAF-IASFPA), S. Dichiara (PSU), R. Gupta (NASA GSFC), H. A. Krimm (NSF), N. P. M. Kuin (UCL-MSSL), A. Y. Lien (U Tampa) and T. M. Parsotan (GSFC) report on behalf of the Neil Gehrels Swift Observatory Team: At 01:36:15 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 241229B (trigger=1277428). Swift did not slew immediately to the burst. The BAT on-board calculated location is RA, Dec 274.149, +74.714 which is RA(J2000) = 18h 16m 36s Dec(J2000) = +74d 42' 50" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 10 sec. The peak count rate was ~3000 counts/sec (15-350 keV), at ~0 sec after the trigger. Due to an observing constraint, Swift cannot slew to the BAT position. There will thus be no XRT or UVOT data for this trigger. Burst Advocate for this burst is A. D'Ai (antonino.dai AT inaf.it). 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/38699. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...