Hamburg, R.R.HamburgFletcher, C.C.FletcherBurns, E.E.BurnsGoldstein, A.A.GoldsteinBissaldi, E.E.BissaldiBriggs, M. S.M. S.BriggsCleveland, W. H.W. H.ClevelandGiles, M. M.M. M.GilesHui, C. M.C. M.HuiKocevski, D.D.KocevskiLesage, S.S.LesageMailyan, B.B.MailyanMalacaria, C.C.MalacariaPoolakkil, S.S.PoolakkilPreece, R.R.PreeceRoberts, O. J.O. J.RobertsVeres, P.P.VeresVon Kienlin, A.A.Von KienlinWilson-Hodge, C. A.C. A.Wilson-HodgeWood, J.J.WoodAbbott, R.R.AbbottAbbott, T. D.T. D.AbbottAbraham, S.S.AbrahamAcernese, F.F.AcerneseAckley, K.K.AckleyAdams, C.C.AdamsAdhikari, R. X.R. X.AdhikariAdya, V. B.V. B.AdyaAffeldt, C.C.AffeldtAgathos, M.M.AgathosAgatsuma, K.K.AgatsumaAggarwal, N.N.AggarwalAguiar, O. D.O. D.AguiarAich, A.A.AichAiello, L.L.AielloAin, A.A.AinAjith, P.P.AjithAllen, G.G.AllenAllocca, A.A.AlloccaAltin, P. A.P. A.AltinAmato, A.A.AmatoAnand, S.S.AnandAnanyeva, A.A.AnanyevaAnderson, S. B.S. B.AndersonAnderson, W. G.W. G.AndersonAngelova, S. V.S. V.AngelovaAnsoldi, S.S.AnsoldiAntier, S.S.AntierAppert, S.S.AppertArai, K.K.AraiAraya, M. C.M. C.ArayaAreeda, J. S.J. S.AreedaArene, M.M.AreneArnaud, N.N.ArnaudAronson, S. M.S. M.AronsonAscenzi, S.S.AscenziAshton, G.G.AshtonAston, S. M.S. M.AstonAstone, P.P.AstoneAubin, F.F.AubinAufmuth, P.P.AufmuthAultoneal, K.K.AultonealAustin, C.C.AustinAvendano, V.V.AvendanoBabak, S.S.BabakBacon, P.P.BaconBadaracco, F.F.BadaraccoBader, M. K.M.M. K.M.BaderBae, S.S.BaeBaer, A. M.A. M.BaerBaird, J.J.BairdBaldaccini, F.F.BaldacciniBallardin, G.G.BallardinBallmer, S. W.S. W.BallmerBals, A.A.BalsBalsamo, A.A.BalsamoBaltus, G.G.BaltusBanagiri, S.S.BanagiriBankar, D.D.BankarBankar, R. S.R. S.BankarBarayoga, J. C.J. C.BarayogaBarbieri, C.C.BarbieriBarish, B. C.B. C.BarishBarker, D.D.BarkerBarkett, K.K.BarkettBarneo, P.P.BarneoBarone, 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.BastiBawaj, M.M.BawajBayley, J. C.J. C.BayleyBazzan, M.M.BazzanBécsy, B.B.BécsyBejger, M.M.Bejger2025-08-312025-08-312020-04-2010.3847/1538-4357/ab7d3e2-s2.0-85085073754https://d8.irins.org/handle/IITG2025/24173We present results from offline searches of Fermi Gamma-ray Burst Monitor (GBM) data for gamma-ray transients coincident with the compact binary coalescences observed by the gravitational-wave (GW) detectors Advanced LIGO and Advanced Virgo during their first and second observing runs. In particular, we perform follow-up for both confirmed events and low significance candidates reported in the LIGO/Virgo catalog GWTC-1. We search for temporal coincidences between these GW signals and GBM-triggered gamma-ray bursts (GRBs). We also use the GBM Untargeted and Targeted subthreshold searches to find coincident gamma-rays below the onboard triggering threshold. This work implements a refined statistical approach by incorporating GW astrophysical source probabilities and GBM visibilities of LIGO/Virgo sky localizations to search for cumulative signatures of coincident subthreshold gamma-rays. All search methods recover the short gamma-ray burst GRB 170817A occurring ∼1.7 s after the binary neutron-star merger GW170817. We also present results from a new search seeking GBM counterparts to LIGO single-interferometer triggers. This search finds a candidate joint event, but given the nature of the GBM signal and localization, as well as the high joint false alarm rate of 1.1 10^-6 Hz, we do not consider it an astrophysical association. We find no additional coincidences.trueArticlehttps://kclpure.kcl.ac.uk/portal/en/publications/a408fddc-38e4-42a0-bc69-30953cff692e1538435720 April 202017100arJournal18