{
  "bibcode": "2020GCN.27130....1L",
  "body": "The LIGO Scientific Collaboration and the Virgo Collaboration report:\n\nWe identified the compact binary merger candidate S200219ac during\nreal-time processing of data from LIGO Hanford Observatory (H1), LIGO\nLivingston Observatory (L1), and Virgo Observatory (V1) at 2020-02-19\n09:44:15.195 UTC (GPS time: 1266140673.195). The candidate was found\nby the PyCBC Live [1], CWB [2], MBTAOnline [3], SPIIR [4], and GstLAL [5]\nanalysis pipelines.\n\nThe delay in issuing the alert was due to a software issue in the\nonline system.\n\nS200219ac is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 1.3e-08 Hz, or about one in 2\nyears. The event's properties can be found at this URL:\nhttps://gracedb.ligo.org/superevents/S200219ac\n\nThe classification of the GW signal, in order of descending\nprobability, is BBH (96%), Terrestrial (4%), BNS (<1%), NSBH\n(<1%) or MassGap (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object has a mass < 3 solar masses (HasNS) is\n<1%. Using the masses and spins inferred from the signal, the\nprobability of matter outside the final compact object (HasRemnant) is\n<1%.\n\nOne sky map is available at this time and can be retrieved from the\nGraceDB event page:\n �� * bayestar.fits.gz, an updated localization generated by BAYESTAR\n[6], distributed via GCN notice about 2 hours after the candidate.\n\nThe preferred sky map at this time is bayestar.fits.gz. For the\nbayestar.fits.gz sky map, the 90% credible region is 1251 deg2.\nMarginalized over the whole sky, the a posteriori luminosity distance\nestimate is 1510 +/- 405 Mpc (a posteriori mean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of\nthis alert, refer to the LIGO/Virgo Public Alerts User Guide\n<https://emfollow.docs.ligo.org/userguide/>.\n\n ��[1] Nitz et al. PRD 98, 024050 (2018)\n ��[2] Klimenko et al. PRD 93, 042004 (2016)\n ��[3] Adams et al. CQG 33, 175012 (2016)\n ��[4] Qi Chu, PhD Thesis, The University of Western Australia (2017)\n ��[5] Messick et al. PRD 95, 042001 (2017)\n ��[6] Singer & Price PRD 93, 024013 (2016)",
  "circularId": 27130,
  "createdOn": 1582116815000,
  "email": "antier@apc.in2p3.fr",
  "subject": "LIGO/Virgo S200219ac: Identification of a GW compact binary merger candidate",
  "submitter": "Sarah Antier at APC  <antier@apc.in2p3.fr>",
  "eventId": "LIGO/Virgo S200219ac"
}