{
  "bibcode": "2016GCN.19448....1P",
  "body": "K.L. Page (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A.\nD'Ai (INAF-IASFPA), T.G.R. Roegiers (PSU), L.M. McCauley (PSU), J.A.\nKennea (PSU), C. Pagani (U. Leicester), A.P. Beardmore (U. Leicester)\nand P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nFermi/LAT-detected burst GRB 160521B (Axelsson et al. GCN Circ. 19444),\ncollecting 2.0 ks of Photon Counting (PC) mode data between T0+41.9 ks\nand T0+47.7 ks. \n\nOne uncatalogued X-ray source has been detected, it is below the RASS\nlimit and shows no definitive signs of fading. Therefore, at the\npresent time we cannot confirm this as the afterglow. Details of this\nsource are given below:\n\nSource 1:\n  RA (J2000.0):  147.6669  =  09:50:40.06\n  Dec (J2000.0): +79.0302  =  +79:01:48.9\n  Error: 4.6 arcsec (radius, 90% conf.)\n  Count-rate: 0.0122 +/- 0.0028 ct s^-1\n  Flux: (5.3 +/- 1.2)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttp://www.swift.ac.uk/ToO_GRBs/00020615.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 19448,
  "createdOn": 1463888303000,
  "email": "kennea@swift.psu.edu",
  "subject": "GRB 160521B: Swift-XRT observations",
  "submitter": "Jamie A. Kennea at PSU/Swift-XRT  <kennea@swift.psu.edu>",
  "eventId": "GRB 160521B"
}