{
  "bibcode": "2019GCN.24950....1L",
  "body": "The LIGO Scientific Collaboration and the Virgo Collaboration report:\r\n\r\n\r\nWe identified the compact binary merger candidate S190701ah during\r\nreal-time processing of data from LIGO Hanford Observatory (H1), LIGO\r\nLivingston Observatory (L1), and Virgo Observatory (V1) at 2019-07-01\r\n20:33:06.578 UTC (GPS time: 1246048404.578). The candidate was found\r\nby the PyCBC Live [1], MBTAOnline [2], SPIIR [3], and GstLAL [4]\r\nanalysis pipelines.\r\n\r\nS190701ah is an event of interest because its false alarm rate, as\r\nestimated by the online analysis, is 1.9e-08 Hz, or about one in 1\r\nyear, 7 months. The event's properties can be found at this URL:\r\n\r\nhttps://gracedb.ligo.org/superevents/S190701ah\r\n\r\nThe classification of the GW signal, in order of descending probability, is BBH (93%),\r\nTerrestrial (7%), BNS (<1%), NSBH (<1%), or MassGap (<1%).\r\n\r\nAssuming the candidate is astrophysical in origin, there is strong\r\nevidence against the lighter compact object having a mass < 3 solar\r\nmasses (HasNS: <1%). Using the masses and spins inferred from the\r\nsignal, there is strong evidence against matter outside the final\r\ncompact object (HasRemnant: <1%).\r\n\r\nOne sky map is available at this time and can be retrieved from the\r\nGraceDB event page:\r\n * bayestar.fits.gz, an updated localization generated by BAYESTAR\r\n[5], distributed via GCN notice about 4 minutes after the candidate\r\n\r\nFor the bayestar.fits.gz sky map, the 90% credible region is well fit\r\nby an ellipse with an area of 67 deg2 described by the following DS9\r\nregion (right ascension, declination, semi-major axis, semi-minor\r\naxis, position angle of the semi-minor axis):\r\n   icrs; ellipse(02h30m42s, -06d53m30s, 8d, 3d, 97d)\r\nMarginalized over the whole sky, the a posteriori luminosity distance\r\nestimate is 1045 +/- 234 Mpc (a posteriori mean +/- standard\r\ndeviation).\r\n\r\n\r\nThere is substantial scattered light noise in L1 for several seconds around the trigger time. This may affect the accuracy of the skymap, but is not expected to affect the significance of the candidate.\r\n\r\nFor further information about analysis methodology and the contents of\r\nthis alert, refer to the LIGO/Virgo Public Alerts User Guide\r\n<https://emfollow.docs.ligo.org/userguide/>.\r\n\r\n [1] Nitz et al. PRD 98, 024050 (2018)\r\n [2] Adams et al. CQG 33, 175012 (2016)\r\n [3] Qi Chu, PhD Thesis, The University of Western Australia (2017)\r\n [4] Messick et al. PRD 95, 042001 (2017)���\r\n [5] Singer & Price PRD 93, 024013 (2016)",
  "circularId": 24950,
  "createdOn": 1562016390000,
  "email": "piotrzk3@uwm.edu",
  "subject": "LIGO/Virgo S190701ah: Identification of a GW compact binary merger candidate",
  "submitter": "Brandon Piotrzkowski at U of Wisconsin-Milwaukee  <piotrzk3@uwm.edu>",
  "eventId": "LIGO/Virgo S190701ah"
}