J/AJ/115/168ivo://CDS.VizieR/J/AJ/115/168doi:10.26093/cds/vizier.51150168CDSChiba M.Yoshii Y.2023-04-06T16:50:27Z2010-01-27T12:53:49ZCDS support team

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

cds-question@unistra.frgiant-starsvariable-starsproper-motionsThe kinematics of 122 red giant and 124 RR Lyrae stars in the solar neighborhood are studied using accurate measurements of their proper motions obtained by the Hipparcos astrometry satellite, combined with their published photometric distances, metal abundances, and radial velocities. A majority of these sample stars have metal abundances of [Fe/H]<=-1 and thus represent the old stellar populations in the Galaxy. The halo component, with [Fe/H]<=-1.6, is characterized by a lack of systemic rotation [(<U>, <V>, <W>)=(16+/-18, -217+/-21, -10+/-12)km/s] and a radially elongated velocity ellipsoid [(<U>, <V>, <W>)=(161+/-10, 115+/-7, 108+/-7)km/s]. About 16% of such metal-poor stars have low orbital eccentricities (e<0.4), and we see no evidence of a correlation between [Fe/H] and e. Based on the model for the e-distribution of orbits, we show that this fraction of low-e stars for [Fe/H]<=-1.6 is explained by the halo component alone, without introducing the extra disk component claimed by recent workers. This is also supported by the absence of a significant change in the e-distribution with height from the Galactic plane. In the intermediate-metallicity range (-1.6<[Fe/H]<=-1), we find that stars with disklike kinematics have only modest effects on the distributions of rotational velocities and e for the sample at |z|<1kpc. This disk component appears to constitute only 10% for -1.6<[Fe/H]<=-1 and 20% for -1.4<[Fe/H]<=-1. It is also verified that this metal-weak disk has a mean rotation of ~195km/s and a vertical extent of 1 kpc, which is consistent with the thick disk's dominating at [Fe/H]=-0.6 to -1. We find no metallicity gradient in the halo, whereas there is an indication of a metallicity gradient in the metal-weak tail of the thick disk. The implications of these results for the early evolution of the Galaxy are also presented.1998AJ....115..168Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/115/168CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/196 : Hipparcos Input Catalogue, Version 2 (Turon+ 1993)I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/115/168https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/115/168http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/115/168https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/115/168https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/115/168http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/115/168GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/115/168/table1 (Program stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/115/168/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/115/168/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/115/168/table1?GETtext/xml+votable180.050000true1.3138444-27.27170810.005555555555555556Hipparcos6/110 382 1294 1663 1679 2058 2089 2484 2629 2921 2997 3049 3712 4037 4286 4479 4762 4942 5621 6051 6301 6567 6744 6934 7174 7251 7456 7518 7710 7767 8064 8294 8314 8354 8439 8466 8523 8773 8779 8866 9027 9065 9138 9363 9509 9769 9938 10169 10328 10362 10476 10541 10584 10602 10638 10898 10985 11098 11123 11197 11492 11538 11576 11961 12512 12743 12773 13205 13680 14217 14373 14874 15106 15220 15714 16018 16022 16115 16513 16582 16602 16698 16739 16776 16808 16821 16849 16867 16893 16912 16923-16924 17099 17158 17234 17328 17412 17578 18177 18425 18553 18945 18990 19076 19110 19169 19333 20097 20267 20303 20390 20497 20541 21127 21146 21182 21269 21533 21961 22111 22293 22558 22913 23192 23428 24683 24685 24866 25199 25491 25569 25595 25607 25611 25803 25953 25963 26044 26079 26109-26110 26131 26260 26281 26304 26344 26347 26366 26380 26435 26457 26487 26515 26534 26552 26589 26756 26981 27091 27333 27711 27763 27767 27796 27824 27833 27998 28143 28155 28227 28426 28582 28674 28701 28813 28966 29548 29703 29769 30055 30923 31390 31411 31451 31456 31592 31648 31658 31683 31743 31757 31866 32254 32352 32636 32663 33076 33134 33342 33465 33996 34096 34171 34240 34537 34559 34593 35151 35423 35514 35532 35551 35611 35686 35750 35768 35813 35875 35907 35989 36135 36221 36363 36365 36407 36535 36605 36704 36755 36781 37185 37970 38087 38393 38456 38506 38755 38809 38868 39152 39360 40222 40337 40351 40627 40651 40806 40882 40988 40998 41022 41191 41318 41831 42053 42138 42260 43317 43360 43405 43468 43498 44106 44208 44326 44498 44575 44771 44793 45086 45164 45286 45676 45796 46023 46069 46373 46520 47092 47342 47419 47596 47618 47821 47876 48113 48228 48459 48636 48764 48798 48824 48911 48916 48937 48946 49063 49086https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/115/168?format=asciiOpticaldefaultJ/AJ/115/168/table1Program starspmDEProper motion in DEmas/yrpos.pm;pos.eq.decfloate_pmDErms uncertainty on pmDEmas/yrstat.error;pos.pm;pos.eq.decfloatDist? Photometric heliocentric distancekpcpos.distancefloatnullablee_Dist? rms uncertainty on Distkpcstat.errorfloatnullable[Fe/H]? Metallicitylog(Sun)phys.abund.Zfloatnullablee_[Fe/H]? rms uncertainty on [Fe/H]log(Sun)stat.error;phys.abund.FefloatnullableRV? Radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloatnullablee_RV? rms uncertainty on RVkm/sstat.errorfloatnullablepmRAo? Old proper motion in RAarcsec/yrpos.pm;pos.eq.rafloatnullablepmDEo? Old proper motion in DEarcsec/yrpos.pm;pos.eq.decfloatnullablerf1References for Dist and [Fe/H] (1)meta.refcharrf2References for RV (2)meta.refcharrf3? References for proper motions (3)meta.refintnullableSimbadSimbad column added by the CDSchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintType[RG] Type of the stars, as RG = Red giants; RR = RR Lyraesrc.classcharHIC(P)HIC or HIP (Cat. I/239) numbermeta.id;meta.mainintNameOther namemeta.idcharplxTrigonometric parallaxmaspos.parallax.trigfloate_plxrms uncertainty on plxmasstat.error;pos.parallaxfloatpmRA*Proper motion in RA time cos{delta}mas/yrpos.pm;pos.eq.rafloate_pmRA*rms uncertainty on pmRA*mas/yrstat.error;pos.pm;pos.eq.rafloat