TITLE: GCN CIRCULAR NUMBER: 42656 SUBJECT: Swift Trigger 1413695: a possible GRB 251112A DATE: 25/11/12 22:04:25 GMT FROM: James DeLaunay at PSU <jjd330@psu.edu> A. Mei (INAF-OAB), J. J. DeLaunay (PSU), M. Ferro (INAF-OAB), R. Gupta (NASA GSFC) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 21:28:56 UT, the Swift Burst Alert Telescope (BAT) triggered and located a possible GRB 251112A (trigger=1413695). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 274.019, +24.226 which is RA(J2000) = 18h 16m 05s Dec(J2000) = 24d 13' 32" 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 60 sec. The peak count rate was ~600 counts/sec (15-350 keV), at ~25 sec after the trigger. The XRT began observing the field at 21:30:22.7 UT, 86.9 seconds after the BAT trigger. No source was detected in 782 s of promptly downlinked data. We are waiting for the full dataset to detect and localise the XRT counterpart. UVOT took a finding chart exposure of 150 seconds with the White filter starting 91 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 25% of the BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the BAT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.161. Due to no credible afterglow candidate in the initial XRT and UVOT data, we for now call this a possible GRB while we wait for additional data for further inspection. Burst Advocate for this burst is A. Mei (alessio.mei 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/42656. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...