J/ApJ/885/9ivo://CDS.VizieR/J/ApJ/885/9doi:10.26093/cds/vizier.18850009CDSTorres G.Stefanik R.P.Latham D.W.2022-03-15T07:55:42Z2021-06-17T07:35:26ZCDS support team

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

cds-question@unistra.frmultiple-starsvisible-astronomyspectroscopyradial-velocityThe star HD28363 in the Hyades cluster has been known for over a century as a visual binary with a period of 40yr. The secondary is, in turn, a single-lined spectroscopic binary with a 21day period. Here we report extensive spectroscopic monitoring of this hierarchical triple system that reveals the spectral lines of the third star for the first time. Combined with astrometric information, this makes it possible to determine the dynamical masses of all three stars. Only six other binaries in the Hyades have had their individual component masses determined dynamically. We infer the properties of the system by combining our radial-velocity measurements with visual observations, lunar occultation measurements, and with proper motions from the Hipparcos and Gaia missions that provide a constraint on the astrometric acceleration. We derive a mass of 1.341_-0.024_^+0.026^M{odot} for the visual primary, and 1.210{+/-}0.021 and 0.781{+/-}0.014 M{sun} for the other two stars. These measurements along with those for the other six systems establish an empirical mass-luminosity relation in the Hyades that is in broad agreement with current models of stellar evolution for the known age and chemical composition of the cluster.2019ApJ...885....9Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/885/9CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/wds : The Washington Visual Double Star Catalog (Mason+, 2001-2020)I/337 : Gaia DR1 (Gaia Collaboration, 2016)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/A+A/341/121 : Visual binary orbits and masses (Soederhjelm 1999J/AJ/124/1144 : Orbits of 171 single-lined spectroscopic binaries (Latham,2002)J/AJ/132/111 : BV(RI)_C_photometry of 77 Hyades stars (Joner+, 2006)J/A+A/498/949 : Velocities 1253 F-K dwarfs in open clusters (Mermilliod+, 2009)J/ApJ/883/105 : PA & angular separation measurements of 80 Tau (Torres, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/885/9https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/885/9http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/885/9https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/885/9https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/885/9http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/885/9GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/ApJ/885/9/table1CfA radial velocities for HD 28363recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJD[44560/56559] Heliocentric Julian Date, JD-2400000dtime.epochdoubleRVelA[28.71/46.98] Radial velocity, component Akm/sphys.veloc;pos.heliocentricfloate_RVelA[0.1/2.6] Uncertainty in RVel-Akm/sstat.error;phys.velocfloatRVelBa[7.1/91.81] Radial velocity, component Bakm/sphys.veloc;pos.heliocentricfloate_RVelBa[0.09/1.9] Uncertainty in RVel-Bakm/sstat.error;phys.velocfloatRVelBb[-40.08/94.8]? Radial velocity, component Bbkm/sphys.veloc;pos.heliocentricfloatnullablee_RVelBb[1.1/16.5]? Uncertainty in RVel-Bbkm/sstat.error;phys.velocfloatnullablePhase-I[0.05/0.87] Inner Orbital phasetime.phasedoublePhase-O[0.0007/1] Outer Orbital phasetime.phasedoubleJ/ApJ/885/9/table2Visual observations of HD 28363recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDate[1904/2017] Julian yearyrtime.epochdoublePA[68.8/275]? Position angledegpos.posAngfloatnullablee_PA[0.001/0.03]? Uncertainty in PA (1)arcsecstat.errordoublenullable(OC)PA[-9.63/23.42]? Residual, Positional Angledegpos.posAngfloatnullable(OC)PA-n[-2.09/2.94]? Normalized Residual, (O-C)PA/(e_PA/Sep)pos.posAngfloatnullableSep[0.07/0.49]? Separationarcsecpos.angDistance;src.orbitalfloatnullablee_Sep[0.0002/0.06]? Uncertainty in Sep (1)arcsecstat.errorfloatnullable(OC)Sep[-0.11/0.1]? Residual, separationarcsecpos.angDistance;src.orbitalfloatnullable(OC)Sep-n[-2.06/2.69]? Normalized Residual, (O-C)Sep/(e_Sep)pos.angDistance;src.orbitalfloatnullable