J/MNRAS/493/2339ivo://CDS.VizieR/J/MNRAS/493/2339doi:10.26093/cds/vizier.74932339CDSMelnik A.M.Dambis A.K.2024-08-20T20:16:16Z2020-03-26T16:43:53ZCDS support team

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

cds-question@unistra.frmilky-way-galaxystellar-associationsob-starsproper-motionsradial-velocityphotometryWe study the motions inside 28 OB-associations with the use of Gaia DR2 proper motions. The average velocity dispersion calculated for 28 OB-associations including more than 20 stars with Gaia DR2 proper motion is sigma_v_=4.5km/s. The median virial and stellar masses of OB-associations are 8.9x10^5^ and 8.1x10^3^M_{sun}_, respectively. The median star-formation efficiency in parent giant molecular clouds appears to be epsilon=1.2%. Gaia DR2 proper motions confirm the expansion in the Per OB1, Car OB1 and Sgr OB1 associations found earlier with Gaia DR1 data. We also detect the expansion in Gem OB1, Ori OB1 and Sco OB1 associations which became possible for the first time now when analyzed with Gaia DR2 proper motions. The analysis of the distribution of OB-stars in the Per OB1 association shows the presence of a shell-like structure with the radius of 40 pc. Probably, the expansion of the Per OB1 association started with the velocity greater than the present-day expansion velocity equal to 5.0+/-1.7km/s.2020MNRAS.493.2339Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/493/2339CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia, 2018)III/213 : General Catalog of mean radial velocities (Barbier-Brossat+, 2000)J/MNRAS/472/3887 : Kinematic data for stars in OB-associations (Melnik+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/493/2339https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/493/2339http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/493/2339https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/493/2339https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/493/2339http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/493/2339GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/493/2339/table1 (Kinematic data for stars in OB-associations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/493/2339/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/493/2339/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/493/2339/table1?GETtext/xml+votable180.050000true265.83161910158-28.675756077080010.0055555555555555565/325 814-815 826 832 900 902 931 3562 3573 3575 3577 3589 3657 3660-3661 3663 3672 3914-3915 5995 6084 7205 7207 7228-7229 9333 9335 9467 9474 9476 9482 9504 10413 10542 10553 10556 10757 6/859 1111 1115 1198 1285 1287 1297-1299 1310 1323 1328-1329 1332 1335 1348 1539 1550 1554 1558 1777 1787 1790 1960 1962 2940 2943 3027 3029 3031 3035 3037-3038 3043 3045 3047 3050-3051 3055 3057-3060 3062-3063 3065-3066 3068 3153 3156 3183 3188 3198 3231 3239 3243-3245 3247 3249-3251 3253-3255 3272 3274-3276 3278-3279 3281-3284 3286-3290 3292-3293 3296-3297 3299-3302 3308 3312 3315 3320 3324 3334 3337 3384 3464 3585 3587 3589 3596-3597 3599 3604 3612 3621-3623 3632-3634 3648-3649 3653 3712 3714-3716 3718-3719 3721-3723 3744 3746-3747 3755 3758 12988-12989 12991 13276 13535 13557 13963 13999 14003-14004 14007-14008 14015 14029 14072 14075 14079 14197 14207 14236-14238 14240 14245-14247 14252-14254 14256 14259-14260 14263-14264 14267-14269 14280 14282-14283 14286-14287 14296-14297 14299 14304 14306-14307 14316-14317 14320 14323-14326 14328 14353 14360 14400 14456 14617 14619 14622-14623 14625 14632-14633 14635-14637 14648-14649 14666 14692-14693 14696 14737 14740-14741 14743 14784 14805 15362 15365 15368-15369 15373 15376 15384 15392 15394 15396 15399 15406 15427 15442 15452 15455 15476 15478-15479 15481 15484 15486 15510 15560-15561 15569 15571-15574 15577 15580 15617 15622-15625 15631 15633 15638 15640 15642 15650 15653 15667-15668 15670 15672 15682-15683 15685-15687 15689 15692 15703 15744-15745 15747-15749 15759 15823 20756 20759 20761 20767 20800 21209 21233 21303 21430 21432 21434-21436 21438-21439 21450 21456 21479 21482 21517 21635 21638 21641 21643-21644 21646-21647 21656 21669 21671 21682 22044-22045 22058 22223 22240 22243-22244 22246 22249 22252-22253 22258 22264 22805 22845 22848-22849 22854 22857-22859 22861 22873 22884 22889 22893 22895 22898 22904 22907 22994-22995 23572 23621 23623 23632 23637 23644 23695 23717 23851 23936 23979 23986 23993-23996 23998 24320 24324-24325 24327 24333-24334 24340 24483 24486 24489 24496-24497 24504 24508 24510-24511 24522 24546 24552 24554-24555 28719 28730 28732 28803 28807 28825 28848 28853 28864 28872 28879 28888 28890-28892 28894 28900 28903 29088-29089 29091-29092 29094-29096 29098 29100-29101 29106-29107 29113 29115-29116 29118-29119 29160 29162-29163 29166 29179 29182 29456-29457 29459-29460 29462-29463 29504 29506-29508 29510 29512-29513 29515 29519-29520 29527 29529 29531 29534-29535 30211 30217 30232 30234 30242 30247 30256 31756 37245 37247 37329 37337 37339 37854 37863 37873-37874 37880 37882-37883 37891 37894-37895 37900-37901 37912 37923 37926-37927 37932-37934 37936 37938 38020 38022 38024-38026 39189 39194 39205-39206 39209 39211 39216-39217 39220 39227 39233 39235-39236 39238 39241 39243-39244 39247-39249 39252 39254 39281 39297 39384 39386 39711 39733 39739 39742-39743 39754 39774-39776 39778 39780 39793 39799 39803-39804 39806-39807 39828 39832 39857 39861 39864 39868 39873 39876 39878 39904 39907 39916 39930 40490 41630-41631 41650-41651 41657 41661-41663 41677 41698-41699 41704 41706-41707 41738 41756 41758 41760-41761 41813 41856 42153-42154 42157 42162-42163 42166 42174 42187 42191 42199 42201-42203 42206 42209 42211 42221 42223 42228 42234-42236 42370 42376 42383 42392 42394-42395 42405 42407-42408 42416-42417 42458 42482-42483 42486 42489 42491 42516 42932 42948 42959 42977 43026-43027 43033-43036 43072 44305 44366 443891.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/493/2339?format=asciidefaultJ/MNRAS/493/2339/table1Kinematic data for stars in OB-associationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharAssName of the OB-associationmeta.idcharSpTypeSpectral type of the starsrc.spTypecharLClassCode of the luminosity class (1)meta.code.multip;src.class.luminosityintVmagApparent V-band magnitude of the starmagphot.mag;em.opt.VfloatrHeliocentric distance of the OB-associationkpcpos.distance;pos.heliocentricfloatRA_ICRS? Barycentric right ascension (ICRS) at Ep=2015.5 (ra) (Gaia DR2)degpos.eq.ra;meta.mainnullableDE_ICRS? Barycentric declination (ICRS) at Ep=2015.5 (dec) (Gaia DR2)degpos.eq.dec;meta.mainnullableGmag? G-band mean magnitude of the star (Gaia DR2)magphot.mag;em.optfloatnullableGLON? Galactic Longitude of the stardegpos.galactic.lonnullableGLAT? Galactic Latitude of the stardegpos.galactic.latdoublenullablePlx? Absolute stellar parallax (Gaia DR2)maspos.parallaxdoublenullablee_Plx? Standard error of parallax (Gaia DR2)masstat.error;pos.parallaxfloatnullablepmGLON? Proper motion along Galactic Longitidemas/yrpos.pmfloatnullablee_pmGLON? Error of pmGLONmas/yrstat.errorfloatnullablepmGLAT? Proper motion along Galactic Latitidemas/yrpos.pmfloatnullablee_pmGLAT? Error of pmGLATmas/yrstat.errorfloatnullableHVR? Heliocentric radial velocity of the starkm/sspect.dopplerVeloc;pos.heliocentricfloatnullablee_HVR? Error of HVRkm/sstat.errorfloatnullableNvis? Number of visibility periodsmeta.numberintnullableRUWE? Re-normalised unit weight errorstat.weightfloatnullableSimbadNameSimbad column added by the CDSmeta.idchar_RA.icrsRight ascension (ICRS) at Epoch=J2015.5 (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) at Epoch=J2015.5 (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decnullableindexed