{
  "bibcode": "2021GCN.29690....1O",
  "body": "J.P. Osborne (U. Leicester), F. Krauss (PSU), T. Gregoire (PSU), P.A. Evans (U.\nLeicester), J.A. Kennea (PSU), H. A. Ayala Solares (PSU), D.F. Cowen (PSU), J.\nDeLaunay (PSU) and D. B. Fox (PSU) report:\n\nSwift has observed the field of the IceCube Astrotrack Bronze\n135113_19489408.amon. 4ks of cleaned XRT data were gathered between 04:55 and\n07:03 UT on 2021 March 22.\n\nA point source is reliably detected at RA, Dec = (85.73812, -44.7522) which is\nequivalent to:\n\n  RA(J2000.0) = 05h 42m 57.15s\n  Dec(J2000.0) = -44d 45��� 07.9���\n\nwith an uncertainty of 5.1��� (radius, 90% confidence). This position is consistent\nwith the source 1RXS J054257.9-444452 in the RASS Faint Source Catalogue. Using\na spectrum fitted to the XRT data, we find that the current 0.3-10 keV flux is\n9.7 (+3.4, -2.7) ��10^-13 erg cm^-2 s^-1, which is about 3.7-sigma above the\ncatalogued flux, suggesting variability or possibly an outburst: however, we\ncaution that the spectral fit is very uncertain, and this flux increase should\nbe viewed with caution.\n\nThe source has no counterpart in SIMBAD, although it is a few arcseconds from a\nWISE object.\n\nGiven the low statistical quality of the XRT spectral information, the lack of\nblazar classification for the RASS source, and the likelihood that the alert was\ncaused by a muon, not an astrophysical neutrino (GCN Circ. 29688), we cannot\nclaim this as a probable counterpart; however, should variability be detected at\nother wavelengths the case for this source as an interesting object would be\nstrengthened.",
  "circularId": 29690,
  "createdOn": 1616430553000,
  "email": "pae9@leicester.ac.uk",
  "subject": "IceCube 135113_19489408.amon: Swift-XRT observations",
  "submitter": "Phil Evans at U of Leicester  <pae9@leicester.ac.uk>"
}