{
  "bibcode": "2018GCN.22630....1L",
  "body": "Z. Liu (NAOC/U. Leicester), A. P. Beardmore (U Leicester),\nA. A. Breeveld (UCL-MSSL), A. Deich (PSU), J.D. Gropp (PSU),\nJ. A. Kennea (PSU), A. Y. Lien (GSFC/UMBC),\nF. E. Marshall (NASA/GSFC), K. L. Page (U Leicester) and\nA. Tohuvavohu (PSU) report on behalf of the Neil Gehrels Swift\nObservatory Team:\n\nAt 12:27:43 UT, the Swift Burst Alert Telescope (BAT) triggered and\nlocated GRB 180411A (trigger=824451).  Swift slewed immediately to the burst. \nThe BAT on-board calculated location is \nRA, Dec 356.829, +66.791 which is \n   RA(J2000) = 23h 47m 19s\n   Dec(J2000) = +66d 47' 26\"\nwith an uncertainty of 3 arcmin (radius, 90% containment, including \nsystematic uncertainty).  The BAT light curve showed a multi-peaked\nstructure with a duration of about 100 sec.  The peak count rate\nwas ~8000 counts/sec (15-350 keV), at ~53 sec after the trigger. \n\nThe XRT began observing the field at 12:28:50.4 UT, 66.7 seconds after\nthe BAT trigger. Using promptly downlinked data we find a bright,\nfading, uncatalogued X-ray source located at RA, Dec 356.85453,\n66.77831 which is equivalent to:\n   RA(J2000)  = 23h 47m 25.09s\n   Dec(J2000) = +66d 46' 41.9\"\nwith an uncertainty of 3.8 arcseconds (radius, 90% containment). This\nlocation is 58 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. \n\nA power-law fit to a spectrum formed from promptly downlinked event\ndata gives a column density in excess of the Galactic value (8.31 x\n10^21 cm^-2, Willingale et al. 2013), with an excess column of 1.2\n(+0.97/-0.75) x 10^22 cm^-2 (90% confidence). \n\nThe initial flux in the 2.5 s image was 1.35e-08 erg cm^-2 s^-1 (0.2-10\nkeV). \n\nThere are no UVOT data available at the present time. \n\nBurst Advocate for this burst is Z. Liu (zl182 AT leicester.ac.uk). \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": 22630,
  "createdOn": 1523450899000,
  "email": "klp5@leicester.ac.uk",
  "subject": "GRB 180411A: Swift detection of a burst",
  "submitter": "Kim Page at U.of Leicester  <klp5@leicester.ac.uk>",
  "eventId": "GRB 180411A"
}