Abbott, B. P.B. P.AbbottAbbott, R.R.AbbottAbbott, T. D.T. D.AbbottAcernese, F.F.AcerneseAckley, K.K.AckleyAdams, C.C.AdamsAdams, T.T.AdamsAddesso, P.P.AddessoAdhikari, R. X.R. X.AdhikariAdya, V. B.V. B.AdyaAffeldt, C.C.AffeldtAfrough, M.M.AfroughAgarwal, B.B.AgarwalAgathos, M.M.AgathosAgatsuma, K.K.AgatsumaAggarwal, N.N.AggarwalAguiar, O. D.O. D.AguiarAiello, L.L.AielloAin, A.A.AinAjith, P.P.AjithAllen, B.B.AllenAllen, G.G.AllenAllocca, A.A.AlloccaAltin, P. A.P. A.AltinAmato, A.A.AmatoAnanyeva, A.A.AnanyevaAnderson, S. B.S. B.AndersonAnderson, W. G.W. G.AndersonAntier, S.S.AntierAppert, S.S.AppertArai, K.K.AraiAraya, M. C.M. C.ArayaAreeda, J. S.J. S.AreedaArnaud, N.N.ArnaudArun, K. G.K. G.ArunAscenzi, S.S.AscenziAshton, G.G.AshtonAst, M.M.AstAston, S. M.S. M.AstonAstone, P.P.AstoneAufmuth, P.P.AufmuthAulbert, C.C.AulbertAultoneal, K.K.AultonealAvila-Alvarez, A.A.Avila-AlvarezBabak, S.S.BabakBacon, P.P.BaconBader, M. K.M.M. K.M.BaderBae, S.S.BaeBaker, P. T.P. T.BakerBaldaccini, F.F.BaldacciniBallardin, G.G.BallardinBallmer, S. W.S. W.BallmerBanagiri, S.S.BanagiriBarayoga, J. C.J. C.BarayogaBarclay, S. E.S. E.BarclayBarish, B. C.B. C.BarishBarker, D.D.BarkerBarone, F.F.BaroneBarr, B.B.BarrBarsotti, L.L.BarsottiBarsuglia, M.M.BarsugliaBarta, D.D.BartaBartlett, J.J.BartlettBartos, I.I.BartosBassiri, R.R.BassiriBasti, A.A.BastiBatch, J. C.J. C.BatchBaune, C.C.BauneBawaj, M.M.BawajBazzan, M.M.BazzanBécsy, B.B.BécsyBeer, C.C.BeerBejger, M.M.BejgerBelahcene, I.I.BelahceneBell, A. S.A. S.BellBerger, B. K.B. K.BergerBergmann, G.G.BergmannBerry, C. P.L.C. P.L.BerryBersanetti, D.D.BersanettiBertolini, A.A.BertoliniBetzwieser, J.J.BetzwieserBhagwat, S.S.BhagwatBhandare, R.R.BhandareBilenko, I. A.I. A.BilenkoBillingsley, G.G.BillingsleyBillman, C. R.C. R.BillmanBirch, J.J.BirchBirney, R.R.BirneyBirnholtz, O.O.BirnholtzBiscans, S.S.BiscansBisht, A.A.BishtBitossi, M.M.BitossiBiwer, C.C.BiwerBizouard, M. A.M. A.BizouardBlackburn, J. K.J. K.BlackburnBlackman, J.J.BlackmanBlair, C. D.C. D.BlairBlair, D. G.D. G.BlairBlair, R. M.R. M.BlairBloemen, S.S.Bloemen2025-08-302025-08-302017-06-0110.1103/PhysRevLett.118.2211012-s2.0-85020048154https://d8.irins.org/handle/IITG2025/2247428621973We describe the observation of GW170104, a gravitational-wave signal produced by the coalescence of a pair of stellar-mass black holes. The signal was measured on January 4, 2017 at 10 11:58.6 UTC by the twin advanced detectors of the Laser Interferometer Gravitational-Wave Observatory during their second observing run, with a network signal-to-noise ratio of 13 and a false alarm rate less than 1 in 70 000 years. The inferred component black hole masses are 31.2-6.0+8.4M' and 19.4-5.9+5.3M (at the 90% credible level). The black hole spins are best constrained through measurement of the effective inspiral spin parameter, a mass-weighted combination of the spin components perpendicular to the orbital plane, χeff=-0.12-0.30+0.21. This result implies that spin configurations with both component spins positively aligned with the orbital angular momentum are disfavored. The source luminosity distance is 880-390+450 Mpc corresponding to a redshift of z=0.18-0.07+0.08. We constrain the magnitude of modifications to the gravitational-wave dispersion relation and perform null tests of general relativity. Assuming that gravitons are dispersed in vacuum like massive particles, we bound the graviton mass to mg≤7.7×10-23 eV/c2. In all cases, we find that GW170104 is consistent with general relativity.falseArticlehttps://kclpure.kcl.ac.uk/ws/files/70750793/GW170104_Observation_of_a_50_ABBOTT_Pub_01June2017_GOLD_VoR_CCBY.pdf107971141 June 20172231221101arJournal1970