{
  "bibcode": "2022GCN.33067....1D",
  "body": "S. Dichiara (PSU), R. A. J. Eyles-Ferris (U Leicester),\nJ.D. Gropp (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL) and\nB. Sbarufatti (INAF-OAB) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 11:21:20 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 221216A (trigger=1144698).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 326.021, -34.405 which is \n   RA(J2000) = 21h 44m 05s\n   Dec(J2000) = -34d 24' 17\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a complex\nstructure with a duration of at least 200 sec.  The peak count rate\nwas ~1640 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 11:22:32.6 UT, 71.7 seconds after\nthe BAT trigger. XRT found a bright, uncatalogued X-ray source located\nat RA, Dec 326.0326, -34.4223 which is equivalent to:\n   RA(J2000)  = 21h 44m 7.82s\n   Dec(J2000) = -34d 25' 20.3\"\nwith an uncertainty of 4.8 arcseconds (radius, 90% containment). No\nevent data are yet available to determine the column density using\nX-ray spectroscopy. \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 81 seconds after the BAT trigger. No credible afterglow candidate has\nbeen found in the initial data products. The 2.7'x2.7' sub-image covers 100% of\nthe XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. \nThe 8'x8' region for the list of sources generated on-board covers 100% of the\nXRT error circle. The list of sources is typically complete to about 18 mag. No\ncorrection has been made for the expected extinction corresponding to E(B-V) of\n0.042. \n\nBurst Advocate for this burst is S. Dichiara (simonedichiara55 AT gmail.com). \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/)",
  "circularId": 33067,
  "createdOn": 1671190465000,
  "email": "kimlpage1978@gmail.com",
  "subject": "GRB 221216A: Swift detection of a burst",
  "submitter": "Kim Page at U.of Leicester  <kimlpage1978@gmail.com>",
  "eventId": "GRB 221216A"
}