{
  "bibcode": "2017GCN.20984....1T",
  "body": "E. Troja (NASA/GSFC/UMCP), S. D. Barthelmy (GSFC),\nD. N. Burrows (PSU), S. B. Cenko (GSFC), A. Cholden-Brown (PSU),\nA. D'Ai (INAF-IASFPA), F. E. Marshall (NASA/GSFC) and\nM. H. Siegel (PSU) report on behalf of the Swift Team:\n\nAt 18:39:48 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 170405A (trigger=745797).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 219.810, -25.244, which is \n   RA(J2000)  =  14h 39m 14s\n   Dec(J2000) = -25d 14' 36\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve shows multiple peaks\nwith a duration of about 180 sec.  The peak count rate\nwas ~4500 counts/sec (15-350 keV), at ~4 sec after the trigger. \n\nThe XRT began observing the field at 18:41:49.0 UT, 120.6 seconds after\nthe BAT trigger. XRT found a bright, uncatalogued X-ray source located\nat RA, Dec 219.8290, -25.2438 which is equivalent to:\n   RA(J2000)  = +14h 39m 18.96s\n   Dec(J2000) = -25d 14' 37.7\"\nwith an uncertainty of 4.7 arcseconds (radius, 90% containment). This\nlocation is 61 arcseconds from the BAT onboard position, within the BAT\nerror circle. No event data are yet available to determine the column\ndensity using X-ray spectroscopy. \n\nUVOT took a finding chart exposure of 150 seconds with the White filter\nstarting 128 seconds after the BAT trigger. There is a candidate afterglow in\nthe rapidly available 2.7'x2.7' sub-image at\n  RA(J2000)  =\t14:39:18.72 = 219.82800\n  DEC(J2000) = -25:14:35.3  = -25.24315\nwith a 90%-confidence error radius of about 0.61 arc sec. This position is 3.7\narc sec. from the center of the XRT error circle. The estimated magnitude is\n16.18 with a 1-sigma error of about  0.14. No correction has been made for the\nexpected extinction corresponding to E(B-V) of 0.09. \n\nBurst Advocate for this burst is E. Troja (eleonora.troja AT nasa.gov). \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": 20984,
  "createdOn": 1491418216000,
  "email": "scott@milkyway.gsfc.nasa.gov",
  "subject": "GRB 170405A: Swift detection of a burst with an optical counterpart",
  "submitter": "Scott Barthelmy at NASA/GSFC  <scott@milkyway.gsfc.nasa.gov>",
  "eventId": "GRB 170405A"
}