{
  "bibcode": "2019GCN.25876....1L",
  "body": "The LIGO Scientific Collaboration and the Virgo Collaboration report:\n\nWe identified the compact binary merger candidate S190930t during real-time\nprocessing of data from LIGO Livingston Observatory (L1) at 2019-09-30\n14:34:07.685 UTC (GPS time: 1253889265.685). The candidate was found by the\nGstLAL [1] analysis pipeline.\n\nS190930t is an event of interest because its false alarm rate, as estimated\nby the online analysis, is 1.5e-08 Hz, or about one in 2 years. The event's\nproperties can be found at this URL:\n\nhttps://gracedb.ligo.org/superevents/S190930t\n\nThe classification of the GW signal, in order of descending probability, is\nNSBH (74%), Terrestrial (26%), BNS (<1%), BBH (<1%), or MassGap (<1%).\n\nAssuming the candidate is astrophysical in origin, there is strong evidence\nfor the lighter compact object having a mass < 3 solar masses (HasNS:\n>99%). Using the masses and spins inferred from the signal, there is strong\nevidence against matter outside the final compact object (HasRemnant: <1%).\n\nData from the LIGO-Livingston detector at the time of the trigger exhibits\nnon-stationarity that is consistent with a known class of transient noise\n[2]. Investigations are ongoing as to the possible impact of this noise\nfeature on the significance, classification, and distance estimate of the\nreported trigger.\n\nOne sky map is available at this time and can be retrieved from the GraceDB\nevent page: * bayestar.fits.gz,0, an updated localization generated by\nBAYESTAR [5], distributed via GCN notice about 6 minutes after the\ncandidate trigger time. For the bayestar.fits.gz,0 sky map, the 90%\ncredible region is 24220 deg2. Marginalized over the whole sky, the a\nposteriori luminosity distance estimate is 108 +/- 38 Mpc (a posteriori\nmean +/- standard deviation).\n\nFor further information about analysis methodology and the contents of this\nalert, refer to the LIGO/Virgo Public Alerts User Guide <\nhttps://emfollow.docs.ligo.org/userguide/>.\n\n [1] Messick et al. PRD 95, 042001 (2017)\n\n [2] Abbott et al. CQG 33, 134001 (2016)",
  "circularId": 25876,
  "createdOn": 1569857361000,
  "email": "olivier.minazzoli@ligo.org",
  "subject": "LIGO/Virgo S190930t: Identification of a GW compact binary merger candidate",
  "submitter": "Olivier Minazzoli at LIGO Virgo Collaboration  <olivier.minazzoli@ligo.org>",
  "eventId": "LIGO/Virgo S190930t"
}