{
  "bibcode": "2017GCN.21474....1L",
  "body": "The LIGO Scientific Collaboration and the Virgo Collaboration report:\n\nThe gstlal CBC analysis (Messick et al. Phys. Rev. D 95, 042001, 2017)\nidentified candidate G297595 during real-time processing of data from\nLIGO Hanford Observatory (H1),  LIGO Livingston Observatory (L1), and\nVirgo Observatory (V1) at 2017-08-14 10:30:43 UTC (GPS time:\n1186741861.5268).\n\nG297595 is an event of interest because its false alarm rate, as\ndetermined by the online analysis, is ~1/80000 years, passing our\nstated alert threshold of ~1/month. The event's properties can be\nfound at this URL:\n          https://gracedb.ligo.org/events/G297595\n\nThis event was also identified in real-time by another CBC pipeline,\nPyCBC (Nitz, et al. 2017, arxiv 1705.01513), and the unmodeled burst\npipelines, cWB (Klimenko et al. Phys. Rev. D 93, 042004 (2016)) and\nLIB (Lynch et al. Phys. Rev. D 95, 104046 (2017)).\n\nThe event appears consistent with the merger of two black holes at\nthis time, and there is little chance either component was a neutron\nstar. For more details on the source classification, please consult\nthis technical document: https://dcc.ligo.org/T1600571/public/main .\n\nThis is among the first GW event candidate detected in coincidence\nwith Advanced LIGO and Advanced Virgo, and the first event candidate\nthat registered loudly enough in Virgo to contribute significantly to\nposition reconstruction.\n\nA rapid localization with distance information generated by the\nBAYESTAR pipeline (e.g., Singer et al. 2016, ApJL 829, 15) is\navailable at this time and can be retrieved from the GraceDB event\npage:\n         bayestar.fits.gz,\nusing data from LIGO Hanford, LIGO Livingston, and Virgo, with\nprobability concentrated in a roughly elliptical region centered at\nR.A.=02h44m, Dec.-45d29m. The 50% credible region spans about 22 deg2\nand the 90% region about 97 deg2.\n\nMarginalized over the whole sky, the a posteriori luminosity distance\nestimate is 550 +/- 130 Mpc.\n\nFor comparison, using data from LIGO Hanford and LIGO Livingston\nalone, the 50% credible region spanned 333 deg2 and the 90% area 1158\ndeg2.\n\nUpdates on our analysis of this event, including updated localizations\nwill be sent as they become available.",
  "circularId": 21474,
  "createdOn": 1502713722000,
  "email": "kats@ligo.mit.edu",
  "subject": "LIGO/Virgo G297595: Identification of a GW Binary Merger Candidate",
  "submitter": "Erik Katsavounidis at MIT  <kats@ligo.mit.edu>",
  "eventId": "LIGO/Virgo G297595"
}