{
"subject": "LIGO/Virgo S190728q: Update on Sky-Localization and Source-Classification",
"bibcode": "2019GCN.25208....1L",
"createdOn": 1564350884000,
"circularId": 25208,
"submitter": "Sarah Antier at APC ",
"email": "antier@apc.in2p3.fr",
"body": "The LIGO Scientific Collaboration and Virgo Collaboration report:\n\nWe have conducted further analysis of the LIGO and Virgo data around\nthe time of the compact binary coalescence (CBC) candidate S190728q\n(GCN 25187). Parameter estimation has been performed using\nLALInference [1] and a new sky map, LALInference.offline.fits.gz,\ndistributed via GCN Notice, is available for retrieval from the\nGraceDB event page:\n\nhttps://gracedb.ligo.org/superevents/S190728q/\n\nLALInference.offline.fits.gz is the preferred sky map at this time.\nThe 90% credible region is 104 deg2. Marginalized over the whole sky,\nthe a posteriori luminosity distance estimate is 874 +/- 171 Mpc\n(a posteriori mean +/- standard deviation).\n\nBased on posterior support from parameter estimation [1,2], under the\nassumption that the candidate S190728q is astrophysical in origin,\nthere is strong evidence against the hypothesis that the lighter\ncompact object has a mass < 3 solar masses (HasNS < 1%) and a\nnegligible probability of having disrupted material outside the final\ncompact object (HasRemnant < 1%). The parameter estimation based\nclassification of the GW signal, in order of descending probability,\nis BBH (95%), MassGap (5%), NSBH (<1%), or BNS (<1%).\n\nThe above mentioned probabilities are based on full exploration of the\nbinary parameter space, and hence are the preferred classification\nresults that supersede the ones stated in GCN 25187.\n\nThe probability of non-astrophysical origin and the false alarm rate\nare not being updated at this time; both measures of significance\nshould be expected to change with offline analyses and continued\nobservations.\n\nFor further information about analysis methodology and the contents\nof this alert, refer to the LIGO/Virgo Public Alerts User Guide\n.\n\n[1] Veitch, et al. PRD 91, 042003 (2015)\n[2] Abbott, et al. PRL 116, 241102 (2016)"
}