{
  "bibcode": "2019GCN.26454....1L",
  "body": "The LIGO Scientific Collaboration and the Virgo Collaboration report:\n\nWe identified the compact binary merger candidate S191216ap during\nreal-time processing of data from LIGO Hanford Observatory (H1) and\nVirgo Observatory (V1) at 2019-12-16 21:33:38.473 UTC (GPS time:\n1260567236.473). The candidate was found by the GstLAL [1], MBTAOnline\n[2], and PyCBC Live [3] analysis pipelines.\n\nS191216ap is an event of interest because its false alarm rate, as\nestimated by the online analysis, is 1.1e-23 Hz, or about one in 1e15\nyears. The event's properties can be found at this URL:\nhttps://gracedb.ligo.org/superevents/S191216ap\n\nThe classification of the GW signal, in order of descending\nprobability, is MassGap (>99%), Terrestrial (<1%), BNS (<1%), BBH\n(<1%), or NSBH (<1%).\n\nAssuming the candidate is astrophysical in origin, the probability\nthat the lighter compact object has a mass < 3 solar masses (HasNS) is\n19%. 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,0, an initial localization generated by BAYESTAR\n[4], distributed via GCN notice about 16 minutes after the candidate\nevent time.\n\nFor the bayestar.fits.gz,0 sky map, the 90% credible region is 300\ndeg2. Marginalized over the whole sky, the a posteriori luminosity\ndistance estimate is 324 +/- 78 Mpc (a posteriori mean +/- standard\ndeviation).\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] Messick et al. PRD 95, 042001 (2017)\n [2] Adams et al. CQG 33, 175012 (2016)\n [3] Nitz et al. PRD 98, 024050 (2018)\n [4] Singer & Price PRD 93, 024013 (2016)",
  "circularId": 26454,
  "createdOn": 1576533835000,
  "email": "piotrzk3@uwm.edu",
  "subject": "LIGO/Virgo S191216ap: Identification of a GW compact binary merger candidate",
  "submitter": "Brandon Piotrzkowski at U of Wisconsin-Milwaukee  <piotrzk3@uwm.edu>",
  "eventId": "LIGO/Virgo S191216ap"
}