J/other/NatAs/9.ivo://CDS.VizieR/J/other/NatAs/9.1337CDSSana H.Shenar T.Bodensteiner J.Britavskiy N.Langer N.Lennon D.J.,Mahy L.Mandel I.de Mink S.E.Patrick L.R.Villasenor J.I.,Abdul-Masih M.Almeida L.A.Backs F.Berlanas S.R.Bernini-Peron M.,Bowman D.M.Bronner V.A.Crowther P.A.Deshmukh K.Evans C.J.Fabry M.,Gieles M.Gilkis A.Gonzalez-Tora G.Grafener G.Gotberg Y.,Hawcroft C.Henault-Brunet V.Herrero A.Holgado G.de Koter A.,Janssens S.Johnston C.Josiek J.Justham S.Kalari V.M.Klencki J.,Kubat J.Kubatova B.Lefever R.R.van Loon J.T.Ludwig B.Mackey J.,Maiz Apellaniz J.Maravelias G.Marchant P.Mazeh T.Menon A.Moe M.,Najarro F.Oskinova L.M.Ovadia R.Pauli D.Pawlak M.Ramachandran V.,Renzo M.Rocha D.F.Sander A.A.C.Schneider F.R.N.Schootemeijer A.,Schosser E.C.Schurmann C.Sen K.Shahaf S.Simon-Diaz S.,van Son L.A.C.Stoop M.Toonen S.Tramper F.Valli R.Vigna-Gomez A.,Vink J.S.Wang C.Willcox R.2026-03-02T06:25:50Z2025-12-01T14:54:14ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frmagellanic-cloudsspectroscopic-binary-starso-starsradial-velocityThe interpretation of observations of gravitational waves, transients, and distant galaxies in the high-redshift Universe heavily relies on our understanding of massive stars at low metallicity. At high metallicity, a majority of massive stars have at least one close stellar companion, which dramatically impacts their evolution, feedback, and final fate. At low metallicity, constraints on the multiplicity of massive stars over the separation range leading to binary interaction have been crucially missing. Here we show that the presence of massive stars in close binaries is ubiquitous, even at low metallicity. The Small Magellanic Cloud is a neighbouring low-metallicity dwarf galaxy with a metal content of about one fifth solar, hence similar to metallicity environments during and before the peak of star formation in the Universe. Using Very Large Telescope spectroscopy from the Binarity at LOw Metallicity large program, we obtained multi-epoch radial velocity measurements of a representative sample of 139 massive O-type stars across the Small Magellanic Cloud. We find that 45% of them show radial velocity variations which demonstrate that they are members of close binary systems, predominantly with orbital periods of less than one year. After correcting for observational biases, we find that at least 0.70^+0.11^_-0.06_ of the O stars in our sample are in close binaries, and that at least 68^+7^-_8_% of all O stars will interact with a companion star during their lifetime. We found no evidence supporting a statistically significant trend of the multiplicity properties with metallicity. Our results indicate that multiplicity and binary interactions govern the evolution of massive stars and determine their cosmic feedback and explosive fates, which has strong implications for our understanding of the high redshift Universe.2025NatAs...9.1337Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/other/NatAs/9.1337CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/690/A289 : Binarity at LOw Metallicity (BLOeM). I. (Shenar+, 2024)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/other/NatAs/9.1337https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/other/NatAs/9.1337http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/other/NatAs/9.1337https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/other/NatAs/9.1337https://vizier.iucaa.in/viz-bin/votable?-source=J/other/NatAs/9.1337http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/other/NatAs/9.1337GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/other/NatAs/9.1337/stars (List of studied stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/other/NatAs/9.1337/stars?https://vizier.iucaa.in/viz-bin/conesearch/J/other/NatAs/9.1337/stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/other/NatAs/9.1337/stars?GETtext/xml+votable180.050000true15.2422083-72.036666670.0055555555555555566/33294-33295 33298 33304 33306 33317 33328https://cdsarc.cds.unistra.fr/viz-bin/moc/J/other/NatAs/9.1337?format=asciidefaultJ/other/NatAs/9.1337/starsList of studied starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintt2indicates information in table 2meta.ref.urlcharObjectBLOeM identifier (BLOeM_N-NNN)meta.id;meta.maincharprimaryRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainVCShow the Radial Velocity curvesmeta.ref.urlcharJ/other/NatAs/9.1337/table1Radial velocity measurementsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObjectBLOeM identifier (BLOeM_N-NNN)meta.id;meta.maincharMJDModified Julian Data at mid-exposuredtime.epochdoubleRVRadial Velocitykm/sphys.veloc;pos.heliocentricfloate_RVUncertainty on the radial Velocitykm/sstat.errorfloatJ/other/NatAs/9.1337/table2Journal of the observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObjectBLOeM identifier (BLOeM_N-NNN)meta.id;meta.maincharNpairsNumber of RV pairs that pass the 4-sigma variability criterion with large (SB) or small (RVvar) RV variation amplitudesmeta.numberintSigniSignificance of the RV variationarith.ratefloatdeltaRVMaximum RV variations between all pairs that meet the variability criteriakm/ssrc.var.amplitudefloatdeltatMinimum time difference between all pairs that meet the variability criteriadsrc.var;arith.diff;stat.minfloatStatusBinary/Variability status (SB or RVvar)meta.codechar