{
  "bibcode": "2017GCN.22020....1B",
  "body": "A. P. Beardmore (U Leicester), A. A. Breeveld (UCL-MSSL),\nJ.D. Gropp (PSU), K. L. Page (U Leicester), T. Sakamoto (AGU) and\nB. Sbarufatti (PSU) report on behalf of the Swift Team:\n\nAt 07:53:29 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated Swift J0243.6+6124 (trigger=779351).  Swift slewed immediately to the \nlocation. The BAT on-board calculated location is RA, Dec 40.908, +61.433 \nwhich is \n   RA(J2000) = 02h 43m 38s\n   Dec(J2000) = +61d 25' 59\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty). The light-curve shows the known 9.86 s periodicity, \nas was noted in GCN 22017. \n\nThe XRT began observing the field at 07:54:27.1 UT, 57.6 seconds after\nthe BAT trigger. XRT found a bright X-ray source located\nat RA, Dec 40.9175, 61.4328 which is equivalent to:\n   RA(J2000)  = +02h 43m 40.20s\n   Dec(J2000) = +61d 25' 58.1\"\nwith an uncertainty of 5.6 arcseconds (radius, 90% containment), \nconsistent with the location of Swift J0243.6+6124. No event data are \nyet available to determine the column density using X-ray spectroscopy. \nThe XRT light-curve also shows the 9.86 s periodicity. \n\nSwift J0243.6+6124 was first detected by Swift/BAT on October 3, 2017\n(GCN 21960; ATel 10809). It has since been brightening in the\ngamma-rays. The daily light curve from the BAT transient monitor is\navailable at\nhttps://swift.gsfc.nasa.gov/results/transients/weak/SwiftJ0243.6p6124/",
  "circularId": 22020,
  "createdOn": 1508142352000,
  "email": "klp5@leicester.ac.uk",
  "subject": "Trigger 779351: Swift detection of Swift J0243.6+6124",
  "submitter": "Kim Page at U.of Leicester  <klp5@leicester.ac.uk>"
}