{
  "eventId": "GRB 250911A",
  "createdOn": 1757555019526,
  "submittedHow": "email",
  "bibcode": "2025GCN.41781....1K",
  "subject": "GRB 250911A: Swift detection of a burst",
  "body": "N. J. Klingler (GSFC/UMBC/CRESSTII), S. Dichiara (PSU),\nR. Gupta (NASA GSFC), A. Y. Lien (U Tampa) and D. M. Palmer (LANL)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 01:27:46 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 250911A (trigger=1348587).  Due to an observing constraint\nSwift did not immediately slew to the burst.\nThe BAT on-board calculated location is \nRA, Dec 263.762, -16.844 which is \n   RA(J2000) = 17h 35m 03s\n   Dec(J2000) = -16d 50' 36\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a complex\nstructure with a duration of about 20 sec.  The peak count rate\nwas ~1200 counts/sec (15-350 keV), at ~3 sec after the trigger.\n\nDue to an observing constraint, Swift will not slew until T0+50\nminutes. There will be no XRT or UVOT data until this time.\n\nBurst Advocate for this burst is N. J. Klingler (noelklin AT umbc.edu).\nPlease contact the BA by email if you require additional information\nregarding Swift followup of this burst. In extremely urgent cases, after\ntrying the Burst Advocate, you can contact the Swift PI by phone (see\nSwift TOO web site for information: http://www.swift.psu.edu/)\n\n",
  "circularId": 41781,
  "submitter": "David Palmer at LANL <palmer@lanl.gov>"
}