J/MNRAS/533/705ivo://CDS.VizieR/J/MNRAS/533/705doi:10.26093/cds/vizier.75330705CDSWright N.J.Jeffries R.D.Jackson R.J.Sacco G.G.Arnold B.,Franciosini E.Gilmore G.Gonneau A.Morbidelli L.Prisinzano L.,Randich S.Worley C.C.2025-02-24T20:16:55Z2024-12-09T08:57:58ZCDS support team

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

cds-question@unistra.frstellar-associationsopen-star-clusterspre-main-sequence-starsWe present the first large-scale 3D kinematic study of ~2700 spectroscopically confirmed young stars (<20Myr) in 18 star clusters and OB associations (hereafter groups) from the combination of Gaia astrometry and Gaia-ESO Survey spectroscopy. We measure 3D velocity dispersions for all groups, which range from 0.61 to 7.4km/s (1D velocity dispersions of 0.35-4.3km/s). We find the majority of groups have anisotropic velocity dispersions, suggesting they are not dynamically relaxed. From the 3D velocity dispersions, measured radii, and estimates of total mass, we estimate the virial state and find that all systems are super-virial when only the stellar mass is considered, but that some systems are sub-virial when the mass of the molecular cloud is taken into account. We observe an approximately linear correlation between the 3D velocity dispersion and the group mass, which would imply that the virial state of groups scales as the square root of the group mass. However, we do not observe a strong correlation between virial state and group mass. In agreement with their virial state, we find that nearly all of the groups studied are in the process of expanding and that the expansion is anisotropic, implying that groups were not spherical prior to expansion. One group, Rho Oph, is found to be contracting and in a sub-virial state (when the mass of the surrounding molecular cloud is considered). This work provides a glimpse of the potential of the combination of Gaia and data from the next generation of spectroscopic surveys.2024MNRAS.533..705Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/533/705CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/533/705https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/533/705http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/533/705https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/533/705https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/533/705http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/533/705GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/533/705/data (young stars with kinematics)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/533/705/data?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/533/705/data?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/533/705/data?GETtext/xml+votable180.050000true160.83685111-59.499876110.0055555555555555565/5934 9239 9282 6/22249 22894-22895 22980-22981 23636-23637 23639 23695 23704-23706 23717 23719 23728 23730 28890-28891 36953 36955 37122-37123 38016 39194 39205 39216-39218 39252 39254 39257 39259-39260 42959 42980-42981 42983 429921.1166583743361574e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/533/705?format=asciidefaultJ/MNRAS/533/705/datayoung stars with kinematicsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRA_ICRSRight Ascension (ICRS) at Ep=2016.0degpos.eq.ra;meta.mainlogg? Spectroscopic surface gravitylog(cm.s**-2)phys.gravityfloatnullablee_logg? Spectroscopic logg errorlog(cm.s**-2)stat.errorfloatnullableGamma? Spectroscopic Gamma indexmeta.code;spect.indexfloatnullablee_Gamma? Spectroscopic Gamma index errorstat.errorfloatnullableTau? Spectroscopic Tau indexspect.indexfloatnullableEWLi? Equivalent Width for the Li 6708 line0.1nmspect.line.eqWidthfloatnullablee_EWLi? Equivalent Width for the Li 6708 line error0.1nmstat.errorfloatnullable_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.raindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decindexedDE_ICRSDeclination (ICRS) at Ep=2016.0degpos.eq.dec;meta.mainGmag? Gaia G-band photometric magnitudemagphot.mag;em.optdoublenullablee_Gmag? Gaia G-band photometric errormagstat.error;phot.magdoublenullableBPmag? Gaia BP-band photometric magnitudemagphot.mag;em.opt.Vdoublenullablee_BPmag? Gaia BP-band photometric errormagstat.error;phot.magdoublenullableRPmag? Gaia RP-band photometric magnitudemagphot.mag;em.opt.Vdoublenullablee_RPmag? Gaia RP-band photometric errormagstat.error;phot.magdoublenullableJmag? 2MASS J-band photometric magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag? 2MASS J-band photometric errormagstat.error;phot.magfloatnullableHmag? 2MASS H-band photometric magnitudemagphot.mag;em.IR.Hfloatnullablee_Hmag? 2MASS H-band photometric errormagstat.error;phot.magfloatnullableKmag? 2MASS K-band photometric magnitudemagphot.mag;em.IR.Kfloatnullablee_Kmag? 2MASS K-band photometric errormagstat.error;phot.magfloatnullablefNIR2MASS Near-IR photometric quality flagmeta.code.qual;photcharRV? Radial velocitykm/sphys.veloc;pos.heliocentricdoublenullablee_RV? Radial velocity errorkm/sstat.errorfloatnullableTeff? Effective temperatureKphys.temperature.effectiveintnullablee_Teff? Effective temperature errorKstat.error;phys.temperature.effectiveintnullablef_TeffFlag indicating how Teff was calculated (2)meta.codecharEWHa? Equivalent Width of H-alpha0.1nmspect.line.eqWidthfloatnullableFWZIHa? Full-Width at Zero Intensity of Halpha0.1nmspect.line.widthfloatnullablee_FWZIHa? Full-Width at Zero Intensity of Halpha error0.1nmstat.errorfloatnullablee_EWHa? Equivalent Width of H-alpha error0.1nmstat.errorfloatnullableHa10? Width of H-alpha at 10%0.1nmspect.line.eqWidthfloatnullablee_Ha10? Width of H-alpha at 10% error0.1nmstat.errorfloatnullablevsini? Rotational velocitykm/sphys.veloc.rotatfloatnullablee_vsini? vsini errorkm/sstat.error;phys.veloc.rotatfloatnullableplx? Gaia parallaxmaspos.parallax.trigfloatnullablee_plx? Gaia parallax errormasstat.error;pos.parallaxfloatnullablepmRA? Proper motion in Right Ascensionmas/yrpos.pm;pos.eq.rafloatnullablee_pmRA? Proper motion in Right Ascension errormas/yrstat.error;pos.pm;pos.eq.rafloatnullablepmDE? Proper motion in Declinationmas/yrpos.pm;pos.eq.decfloatnullablee_pmDE? Proper motion in Declination errormas/yrstat.error;pos.pm;pos.eq.decfloatnullableFpos[G2] G for (ICRS) at Ep=2016.0, 2 for J2000 (1)meta.codechar