{
  "bibcode": "2018GCN.23074....1D",
  "body": "P. D'Avanzo (INAF-OAB), S. D. Barthelmy (GSFC),\nS. W. K Emery (UCL-MSSL), N. P. M. Kuin (UCL-MSSL),\nA. Y. Lien (GSFC/UMBC), A. Melandri (INAF-OAB),\nM. J. Moss (George Washington University) and B. Sbarufatti (PSU)\nreport on behalf of the Neil Gehrels Swift Observatory Team:\n\nAt 09:04:49 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 180805A (trigger=851829).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 167.530, -45.331 which is \n   RA(J2000) = 11h 10m 07s\n   Dec(J2000) = -45d 19' 50\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a single-peaked\nstructure with a duration of about 1.5 sec.  The peak count rate\nwas ~1500 counts/sec (15-350 keV), at ~0 sec after the trigger. \n\nThe XRT began observing the field at 09:06:15.1 UT, 86.1 seconds after\nthe BAT trigger. Using promptly downlinked data we find an uncatalogued\nX-ray source with an enhanced position: RA, Dec 167.5646, -45.3307\nwhich is equivalent to:\n   RA(J2000)  = 11h 10m 15.50s\n   Dec(J2000) = -45d 19' 50.5\"\nwith an uncertainty of 3.8 arcseconds (radius, 90% containment). This\nlocation is 87 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. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density consistent with the Galactic value of 1.68\nx 10^21 cm^-2 (Willingale et al. 2013). \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 89 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 none of\nthe XRT error circle. The 8'x8' region for the list of sources generated\non-board covers 100% of the XRT error circle. The list of sources is typically\ncomplete to about 18 mag. No correction has been made for the expected\nextinction corresponding to E(B-V) of 0.19. \n\nBurst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT brera.inaf.it). \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": 23074,
  "createdOn": 1533461019000,
  "email": "scott@milkyway.gsfc.nasa.gov",
  "subject": "GRB 180805A: Swift detection of a burst",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>",
  "eventId": "GRB 180805A"
}