J/A+A/666/A23ivo://CDS.VizieR/J/A+A/666/A23doi:10.26093/cds/vizier.36660023CDSMayer P.Harmanec P.Zasche P.. Broz M.Catalan-Hurtado R.Barlow B.N.,Frondorf W.Wolf M.Drechsel H.Chini R.Nasseri A.Pigulski A.,Labadie-Bartz J.Christie G.W.Walker W.S.G.Blackford M.Blane D.,Henden A.A.Bohlsen T.Bozic H.Jonak J.2023-07-03T14:20:51Z2022-09-30T08:04:15ZCDS support team

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

cds-question@unistra.freclipsing-binary-starsinfrared-photometryvisible-astronomybroad-band-photometryThe hot nine-component system HD 93206, which contains a gravitationally bounded eclipsing Ac1+Ac2 binary (P=5.9987d) and a spectroscopic Aa1+Aa2 (P=20.734d) binary can provide important insights into the origin and evolution of massive stars. Using archival and new spectra, and a rich collection of ground-based and space photometric observations, we carried out a detailed study of this object. We provide a much improved description of both short orbits and a good estimate of the mutual period of both binaries of about 14500d (i.e. 40 years). For the first time, we detected weak lines of the fainter component of the 6.0d eclipsing binary in the optical region of the spectrum, measured their radial velocities, and derived a mass ratio of M_Ac2_/M_Ac1_=1.29, which is the opposite of what was estimated from the International Ultraviolet explorer (IUE) spectra. We confirm that the eclipsing subsystem Ac is semi-detached and is therefore in a phase of large-scale mass transfer between its components. The Roche-lobe filling and spectroscopically brighter component Ac1 is the less massive of the two and is eclipsed in the secondary minimum. We show that the bulk of the H{alpha} emission, so far believed to be associated with the eclipsing system, moves with the primary O9.7 I component Aa1 of the 20.73d spectroscopic binary. However, the weak emission in the higher Balmer lines seems to be associated with the accretion disc around component Ac2. We demonstrate that accurate masses and other basic physical properties including the distance of this unique system can be obtained but require a more sophisticated modelling. A first step in this direction is presented in the accompanying Paper II (Broz et al., 2022A&A...666A..24B).2022A&A...666A..23Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/666/A23CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/666/A23https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/666/A23http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/666/A23https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/666/A23https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/666/A23http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/666/A23GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tap2.762881831355591e-19 6.118840631666147e-19OpticalInfrareddefaultJ/A+A/666/A23/table6aUBV photometryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDHeliocentric Julian date (JD-2400000.0)dtime.epochdoubleVmagJohnson V magnitudemagphot.mag;em.opt.VfloatBmag? Johnson B magnitudemagphot.mag;em.opt.BfloatnullableUmag? Johnson U magnitudemagphot.mag;em.opt.UfloatnullableB-V? Johnson B-V colour indexmagphot.color;em.opt.B;em.opt.VfloatnullableU-B? Johnson U-B colour indexmagphot.color;em.opt.U;em.opt.BfloatnullableXAir mass of the variableobs.airMassfloatdXAir-mass difference variable minus comparisonobs.airMass;arith.difffloatHDcompHD number of the comparison star usedmeta.id;meta.mainintstaNumerical code of the observing stationmeta.id;instrintJ/A+A/666/A23/table6bBVR photometryXAir mass of the variableobs.airMassfloatdXAir-mass difference variable minus comparisonobs.airMass;arith.difffloatHDcompHD number of the comparison star usedmeta.id;meta.mainintstaNumerical code of the observing stationmeta.id;instrintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDHeliocentric Julian date (JD-2400000.0)dtime.epochdoubleVmagJohnson V magnitudemagphot.mag;em.opt.VfloatBmagJohnson B magnitudemagphot.mag;em.opt.BfloatRmagCousins R magnitudemagphot.mag;em.opt.RfloatB-VJohnson B-V colour indexmagphot.color;em.opt.B;em.opt.VfloatV-RCousins V-R colour indexmagphot.color;em.opt.V;em.opt.RfloatJ/A+A/666/A23/table6cBVRI photometryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDHeliocentric Julian date (JD-2400000.0)dtime.epochdoubleVmagJohnson V magnitudemagphot.mag;em.opt.VfloatB-VJohnson B-V colour indexmagphot.color;em.opt.B;em.opt.VfloatV-R? Cousins V-R colour indexmagphot.color;em.opt.V;em.opt.RfloatnullableR-I? Cousins R-I colour indexmagphot.color;em.opt.R;em.opt.IfloatnullableV-I? Cousins V-I colour indexmagphot.color;em.opt.V;em.opt.IfloatnullablestaNumerical code of the observing stationmeta.codeintJ/A+A/666/A23/table6dV ASAS3 cleaned photometry (station 93)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRJDHeliocentric Julian date (JD-2400000.0)dtime.epochdoubleVmagJohnson V magnitudemagphot.mag;em.opt.Vfloate_VmagStandard error on Vmagmagstat.error;phot.magfloat