J/MNRAS/465/784ivo://CDS.VizieR/J/MNRAS/465/784doi:10.26093/cds/vizier.74650784CDSMarco A.Negueruela I.2024-08-17T20:17:26Z2017-01-11T15:34:48ZCDS support team

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

cds-question@unistra.fropen-star-clustersinfrared-photometryvisible-astronomybroad-band-photometryThe open cluster Berkeley 90 is the home to one of the most massive binary systems in the Galaxy, LS III +46 11, formed by two identical, very massive stars (O3.5 If* + O3.5 If*), and a second early-O system (LS III +46 12 with an O4.5 IV((f)) component at least). Stars with spectral types earlier than O4 are very scarce in the Milky Way, with no more than 20 examples. The formation of such massive stars is still an open question today, and thus the study of the environments where the most massive stars are found can shed some light on this topic. To this aim, we determine the properties and characterize the population of Berkeley 90 using optical, near-infrared and WISE photometry and optical spectroscopy. This is the first determination of these parameters with accuracy. We find a distance of 3.5+/-0.5kpc and a maximum age of 3Ma. The cluster mass is around 1000M_{sun}_ (perhaps reaching 1500M_{sun}_ if the surrounding population is added), and we do not detect candidate runaway stars in the area. There is a second population of young stars to the Southeast of the cluster that may have formed at the same time or slightly later, with some evidence for low-activity ongoing star formation.2017MNRAS.465..784Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/465/784CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/465/784https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/465/784http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/465/784https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/465/784https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/465/784http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/465/784GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/465/784/tablea1 (Coordinates in J2000 and UBVR photometry for all stars in the field of Berkeley 90)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/465/784/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/465/784/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/465/784/tablea1?GETtext/xml+votable180.050000true308.86237546.79786110.005555555555555556Cone search capability for table J/MNRAS/465/784/tablea2 (Coordinates in J2000 and near-IR photometry for stars in the field of Berkeley 90)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/465/784/tablea2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/465/784/tablea2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/465/784/tablea2?GETtext/xml+votable180.050000true308.793791746.81536110.0055555555555555566/14717 147198.650015785639275e-20 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/465/784?format=asciiOpticalInfrareddefaultJ/MNRAS/465/784/tablea1Coordinates in J2000 and UBVR photometry for all stars in the field of Berkeley 90recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainStarThe identification of the star with optical photometry in the field of Berkeley 90meta.id;phot;em.optintVmagJohnson V-band magnitudemagphot.mag;em.opt.Vfloate_Vmagrms uncertainty on Vmagmagstat.error;phot.mag;em.opt.VfloatB-VJohnson (B-V) colour indexmagphot.color;em.opt.B;em.opt.Vfloate_B-Vrms uncertainty on (B-V) (1)magstat.error;phot.color;em.opt.BfloatU-BJohnson (U-B) colour indexmagphot.color;em.opt.U;em.opt.Bfloate_U-Brms uncertainty on (U-B) (1)magstat.error;phot.color;em.opt.UfloatV-RJohnson (V-R) colour indexmagphot.color;em.opt.V;em.opt.Rfloate_V-Rrms uncertainty on (V-R) (1)magstat.error;phot.color;em.opt.VfloatNNumber of measurements for each starmeta.numberintJ/MNRAS/465/784/tablea2Coordinates in J2000 and near-IR photometry for stars in the field of Berkeley 90recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainJmagUKIDSS J magnitude in 2MASS photometric systemmagphot.mag;em.IR.Jfloate_Jmagrms uncertainty on Jmag (1)magstat.error;phot.mag;em.IR.JfloatHmagUKIDSS H magnitude in 2MASS photometric systemmagphot.mag;em.IR.Hfloate_Hmagrms uncertainty on Hmag (1)magstat.error;phot.mag;em.IR.HfloatKsmagUKIDSS Ks magnitude in 2MASS photometric systemmagphot.mag;em.IR.Kfloate_Ksmagrms uncertainty on Ksmag (1)magstat.error;phot.mag;em.IR.Kfloat