J/A+A/626/A17ivo://CDS.VizieR/J/A+A/626/A17doi:10.26093/cds/vizier.36260017CDSCantat-Gaudin T.Jordi C.Wright N.J.Armstrong J.J.Vallenari A.,Balaguer-Nunez L.Ramos P.Bossini D.Padoan P.Pelkonen V.M.,Mapelli M.Jeries R.D.2019-07-26T08:57:02Z2019-06-05T08:07:16ZCDS support team

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

cds-question@unistra.fropen-star-clustersearly-type-starsThe Vela-Puppis region is known to host the Vela OB2 association as well as several young clusters featuring OB and pre-main-sequence stars. Several spatial and kinematic subgroups have been identified in recent years. By grouping stars based on their positions and velocity, we can address the question of the dynamical history of the region and the mechanisms that drove stellar formation. The Gaia DR2 astrometry and photometry enables us to characterise the 3D spatial and 3D kinematic distribution of young stars and to estimate the ages of the identified components. We used an unsupervised classification method to group stars based on their proper motions and parallax. We studied the expansion rates of the different identified groups based on 3D velocities and on corrected tangential velocities. We used theoretical isochrones to estimate ages. The young stars can be separated into seven main groups of different ages and kinematical distribution. All groups are found to be expanding, although the expansion is mostly not isotropic. The size of the region, the age substructure, and the anisotropic expansion rates are compatible with a prolonged period of star formation in a turbulent molecular cloud. The current kinematics of the stars cannot be explained by internal processes alone (such as gas expulsion).2019A&A...626A..17Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/626/A17CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/626/A17https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/626/A17http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/626/A17https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/626/A17https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/626/A17http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/626/A17GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/626/A17/listmemb (List of members of the young populations established in this study)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/626/A17/listmemb?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/626/A17/listmemb?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/626/A17/listmemb?GETtext/xml+votable180.050000true134.234832324891-52.01801797800330.0055555555555555562/153 3/591 620 4/2363 2471 2484 2488 5/9439 9442-9443 9445-9447 9449-9451 9610 9632 9634 9640 9642 9749 9751 9757 9759 9781 9783 9789 9791 9877-9879 9909 9911 9917 9940-9942 9944-9946 9948-9949 9956-9958 9984 9986 9992 9994 10018 10024 6/37597 37599 37620-37621 37623 37627 37629-37631 37739 37742-37743 37753-37755 37777-37779 37793-37795 38445 38447 38532-38534 38540 38542-38543 38564 38566 38572 38574 39001 39003 39033 39121 39123 39129 39131 39153-39155 39161 39163 39504-39506 39632-39633 39635 39772-39773 39775 39788-39790 39800-39802 39804 39806 39836-39837 39841 39844 39872-39873 39875 39877-39878 39888-39889 39942 40064 40066-40067 40105-40107 40110 40448-40450 40452 40454 40456-40458 40460 40462 40480 40483 40488-40489 40492https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/626/A17?format=asciidefaultJ/A+A/626/A17/listmembList of members of the young populations established in this studyrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRA_ICRSGaia DR2 Barycentric right ascension (ICRS) at Ep=2015.5 (ra)degpos.eq.ra;meta.mainDE_ICRSGaia DR2 Barycentric declination (ICRS) at Ep=2015.5 (dec)degpos.eq.dec;meta.mainSourceGaia DR2 Unique source identifier (source_id)meta.id;meta.mainGLONGaia DR2 Galactic longitude (l)degpos.galactic.lonGLATGaia DR2 Galactic latitude(b)degpos.galactic.latdoublePlxGaia DR2 Absolute stellar parallax (parallax)maspos.parallaxdoublee_PlxGaia DR2 Standard error of parallax (parallax_error)masstat.error;pos.parallaxdoublepmRAProper motion in right ascension direction (pmRA*cosDE) (pmra)mas/yrpos.pm;pos.eq.radoublee_pmRAStandard error of proper motion in right ascension direction (pmra_error)mas/yrstat.error;pos.pm;pos.eq.radoublepmDEProper motion in declination direction (pmdec)mas/yrpos.pm;pos.eq.decdoublee_pmDEStandard error of proper motion in declination direction (pmdec_error)mas/yrstat.error;pos.pm;pos.eq.decdoubleRADEcorCorrelation between right ascension and declination (ra_dec_corr)stat.correlationRAPlxcorCorrelation between right ascension and parallax (ra_parallax_corr)stat.correlationRApmRAcorCorrelation between right ascension and proper motion in right ascension (ra_pmra_corrstat.correlationRApmDEcorCorrelation between right ascension and proper motion in declination (ra_pmdec_corr)stat.correlationDEPlxcorCorrelation between declination and parallax (dec_parallax_corr)stat.correlationDEpmRAcorCorrelation between declination and proper motion in right ascension (dec_pmra_corr)stat.correlationDEpmDEcorCorrelation between declination and proper motion in declination (dec_pmdec_corr)stat.correlationPlxpmRAcorCorrelation between parallax and proper motion in right ascension (parallax_pmra_corr)stat.correlationdoublePlxpmDEcorCorrelation between parallax and proper motion in declination (parallax_pmdec_corr)stat.correlationdoublepmRApmDEcorCorrelation between proper motion in right ascension and proper motion in declination (pmra_pmdec_corr)stat.correlationdoubleo_GmagNumber of observations contributing to G photometry (phot_g_n_obs)meta.numberintGmagG-band mean magnitude (Vega) (phot_g_mean_mag)magphot.mag;em.optdoubleBPmag? Integrated BP mean magnitude (Vega) (bp)magphot.mag;em.opt.BdoublenullableRPmag? Integrated GP mean magnitude (Vega) (rp)magphot.mag;em.opt.RdoublenullableBP-RP? BP-RP colour (bp_rp)magphot.color;em.opt.B;em.opt.RdoublenullableRV? Gaia DR2 Spectroscopic radial velocity in the solar barycentric reference frame (radial_velocity)km/sphys.veloc;pos.heliocentricdoublenullablee_RV? Radial velocity error (radial_velocity_error)km/sstat.errordoublenullablechi2ALAL chi-square value (astrometric_chi2_al)stat.fit.paramdoubleNgALNumber of good observations AL (astrometric_n_good_obs_al)meta.numberintE(BR/RP)? BP/RP excess factor (phot_bp_rp_excess_factor)phot.color.excessdoublenullableProbClustering score from UPMASK (probability)meta.notedoubleXGalactic X position (x)pcpos.cartesian.x;pos.galacticdoubleYGalactic Y position (y)pcpos.cartesian.y;pos.galacticdoubleZGalactic Z position (z)pcpos.cartesian.z;pos.galacticdoublePop[1/7] Population, see Sect. 5 (population)meta.code.classint_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decnullableindexed