TITLE: GCN CIRCULAR NUMBER: 36626 SUBJECT: Swift Trigger 1235109: a possible GRB 240606A DATE: 24/06/06 04:07:34 GMT FROM: Mike Siegel at PSU/Swift MOC <siegel@swift.psu.edu> A. D'Ai (INAF-IASFPA), R. Gupta (NASA/GSFC), A. Y. Lien (U Tampa) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 03:33:46 UT, the Swift Burst Alert Telescope (BAT) triggered and located a possible GRB 240606A (trigger=1235109). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 12.125, -19.747 which is RA(J2000) = 00h 48m 30s Dec(J2000) = -19d 44' 49" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve does not show any obvious structure. The XRT began observing the field at 03:35:56.7 UT, 129.8 seconds after the BAT trigger. No source was detected in 1.7 ks of promptly downlinked data. We are waiting for the full dataset to detect and localise the XRT counterpart. UVOT data are unavailable at this time. Due to the marginal significance of the BAT image (6.54 sigma), and the lack of an observed counterpart in the XRT data, this trigger may be due to a noise fluctuation. Further ground data are required to determine the nature of 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/36626. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...