J/AJ/138/1681ivo://CDS.VizieR/J/AJ/138/1681doi:10.26093/cds/vizier.51381681CDSSion E.M.Holberg J.B.Oswalt T.D.McCook G.P.Wasatonic R.2017-06-13T11:09:10Z2012-02-16T11:16:34ZCDS support team

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

cds-question@unistra.frwhite-dwarf-starsstellar-distancestellar-agesstellar-spectral-typesWe present the kinematical properties, distribution of spectroscopic subtypes, and stellar population subcomponents of the white dwarfs within 20pc of the Sun. We find no convincing evidence of halo white dwarfs in the total 20pc sample of 129 white dwarfs nor is there convincing evidence of genuine thick disk subcomponent members within 20 parsecs. Virtually, the entire 20pc sample likely belongs to the thin disk. The total DA to non-DA ratio of the 20pc sample is 1.6, a manifestation of deepening envelope convection which transforms DA stars with sufficiently thin H surface layers into non-DAs. The addition of five new stars to the 20pc sample yields a revised local space density of white dwarfs of (4.9+/-0.5)x10^-3^pc^-3^ and a corresponding mass density of (3.3+/-0.3)x10^-3^M_{sun}_pc^-3^. We find that at least 15% of the white dwarfs within 20 parsecs of the Sun (the DAZ and DZ stars) have photospheric metals that possibly originate from accretion of circumstellar material (debris disks) around them. If this interpretation is correct, this suggests the possibility that the same percentage have planets or asteroid-like bodies orbiting them.2009AJ....138.1681Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/138/1681CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/wd : Spectroscopically Identified White Dwarfs (McCook+, 2008)V/32 : Stars within 25pc of the Sun (Woolley+ 1970)J/AJ/135/1225 : Parameters of the local white dwarfs (Holberg+, 2008)J/AJ/135/1239 : Spectral distances to DA white dwarfs (Holberg+, 2008)J/AJ/134/252 : New nearby white dwarf systems (Subasavage+, 2007)J/ApJ/643/402 : Cool white dwarfs in the solar neighborhood (Kawka+, 2006)J/ApJ/571/512 : Distances of white dwarf stars (Holberg+, 2002)http://www.astro.umontreal.ca/~bergeron/CoolingModels/ : Synthetic colors andhttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/138/1681https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/138/1681http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/138/1681https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/138/1681https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/138/1681http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/138/1681GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/138/1681/WD20pc (Observational data , derived space motions , and cooling times of white dwarfs within 20pc)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/138/1681/WD20pc?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/138/1681/WD20pc?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/138/1681/WD20pc?GETtext/xml+votable180.050000true0.667-34.22741670.0055555555555555566/319 1077 2183 2366 2497 2536 2733 2808 3222 3345 3682 4566 6104 6328 6576 6705 6934 7267 7478 7652 7740 8894 9458 9606 9985 10169 10173 11645 12157 12268 12738 13013 13103 13295 14391 14586 15280 15335 15462 16078 16433 16697 17181 17331 17625 18139 18415 18556 18902 19987 20155 20404 20940 21479 21691 22214 22300 22345 22638 22709 22870 22936 23174 23235 23457 23497 23591 24713 24795 25250 25255 25792 26321 26386 26471 26740 28271 28559 29777 29855 30093 30694 31179 31677 31735 31956 32436 33015 33243 33322 33384 35079 35412 35490 35957 36416 36567 37464 37473 37477 37523 37890 38188 39535 39709 39807 40070 40283 40623 40747 41125 41638 42700 42760 43239 43537 44639 45110 45173 45177 45782 46598 46709 46841 47957 49125https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/138/1681?format=asciiOpticaldefaultJ/AJ/138/1681/WD20pcObservational data , derived space motions , and cooling times of white dwarfs within 20pcSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWDWD designation (HHMM+DDd.N; B1950)meta.id;meta.maincharSpTSpectral typesrc.spTypecharDistDistance (1)pcpos.distance;pos.heliocentricfloatn_Dist[psa] Method of distance determination (3)meta.notecharpmProper motion (2)arcsec/yrpos.pmfloatpmPAPosition angle of proper motiondegpos.pm;pos.posAngfloatUvelU-component (4)km/sphys.veloc;pos.cartesian.xfloatVvelV-component (4)km/sphys.veloc;pos.cartesian.yfloatWvelW-component (4)km/sphys.veloc;pos.cartesian.zfloatTvelThe total space velocitykm/sphys.velocfloatTeffEffective temperatureKphys.temperature.effectiveintnullableloggSurface gravitylog(cm.s**-2)phys.gravityfloatnullableAgeCooling ageyrtime.agedoublenullableLS08Display the data from the local sample of WD from Holdberg et al., 2008, Cat. J/AJ/135/1225meta.ref.urlchar_RAPositions from SIMBAD database (right ascension part)degpos.eq.ra;meta.main_DEPositions from SIMBAD database (declination part)degpos.eq.dec;meta.main