{
  "bibcode": "2018GCN.23169....1S",
  "body": "B. Sbarufatti (PSU), H. A. Krimm (NSF/USRA),\nF. E. Marshall (NASA/GSFC) and A. Tohuvavohu (PSU) report on behalf of\nthe Neil Gehrels Swift Observatory Team:\n\nAt 19:04:32 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 180823A (trigger=855434).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 210.349, +14.884 which is \n   RA(J2000) = 14h 01m 24s\n   Dec(J2000) = +14d 53' 03\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve, which is superimposed \non a declining background, shows a double-peaked structure with a \nduration of about 40 sec.  The peak count rate was ~2000 counts/sec \n(15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 19:06:02.2 UT, 89.2 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright,\nuncatalogued X-ray source located at RA, Dec 210.35630, 14.89029 which\nis equivalent to:\n   RA(J2000)  = 14h 01m 25.51s\n   Dec(J2000) = +14d 53' 25.0\"\nwith an uncertainty of 5.4 arcseconds (radius, 90% containment). This\nlocation is 34 arcseconds from the BAT onboard position, within the BAT\nerror circle. This position may be improved as more data are received;\nthe latest position is available at http://www.swift.ac.uk/sper.  We\ncannot determine whether the source is fading at the present time. No\nspectrum from the promptly downlinked event data is yet available to\ndetermine the column density. \n\nThe initial flux in the 2.5 s image was 3.10e-09 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nUVOT took a finding chart exposure of  37 seconds with the White\nfilter  starting 379 seconds after the BAT trigger. No credible\nafterglow candidate has  been found in the initial data products. The\n2.7'x2.7' sub-image covers 100% of  the XRT error circle. The typical\n3-sigma upper limit is expected to be  about 18.5 mag. No correction\nhas been made  for the expected extinction corresponding to E(B-V) of\n0.02. \n\nBurst Advocate for this burst is B. Sbarufatti (bxs60 AT psu.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/too.html.)",
  "circularId": 23169,
  "createdOn": 1535052699000,
  "email": "aaronb@swift.psu.edu",
  "subject": "GRB 180823A: Swift detection of a burst",
  "submitter": "Aaron Tohuvavohu at PSU/Swift  <aaronb@swift.psu.edu>",
  "eventId": "GRB 180823A"
}