J/A+A/618/A121ivo://CDS.VizieR/J/A+A/618/A121doi:10.26093/cds/vizier.36180121CDSChemin L.2023-12-21T15:31:38Z2018-10-23T08:56:09ZCDS support team

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

cds-question@unistra.frsurveysgalaxiescatalogsgalaxy-classification-systemsThe ellipsoid of stellar random motions is a fundamental ingredient of galaxy dynamics. Yet it has long been difficult to constrain this component in disks others than the Milky Way. This article presents the modeling of the azimuthal-to-radial axis ratio of the velocity ellipsoid of galactic disks from stellar dispersion maps using integral field spectroscopy data of the CALIFA survey. The measured azimuthal anisotropy is shown to be not strongly dependent on the assumed vertical-to-radial dispersion ratio of the ellipsoid. The anisotropy distribution shows a large diversity in the orbital structure of disk galaxies from tangential to radial stellar orbits. Globally, the orbits are isotropic in inner disk regions and become more radial as a function of radius, although this picture tends to depend on galaxy morphology and luminosity. The Milky Way orbital anisotropy profile measured from the Second Gaia Data Release is consistent with those of CALIFA galaxies. A new correlation is evidenced, linking the absolute magnitude or stellar mass of the disks to the azimuthal anisotropy. More luminous disks have more radial orbits and less luminous disks have isotropic and somewhat tangential orbits. This correlation is consistent with the picture in galaxy evolution in which orbits become more radial as the mass grows and is redistributed as a function of time. With the help of circular velocity curves, it is also shown that the epicycle theory fails to reproduce the diversity of the azimuthal anisotropy of stellar random motions, as it predicts only nearly radial orbits in the presence of flat curves. The origin of this conflict is yet to be identified. It also questions the validity of the vertical-to-radial axis ratio of the velocity ellipsoid derived by many studies in the framework of the epicyclic approximation.2018A&A...618A.121Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/618/A121CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/597/A48 : Stellar kinematics in CALIFA survey (Falcon-Barroso+, 2017)J/A+A/598/A32 : 2D decomposition of CALIFA galaxies (Mendez-Abreu+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/618/A121https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/618/A121http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/618/A121https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/618/A121https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/618/A121http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/618/A121GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/618/A121/table1 (Disk galaxies from the CALIFA sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/618/A121/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/618/A121/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/618/A121/table1?GETtext/xml+votable180.050000true167.776486943.63297610.0055555555555555566/995 2248 2251 2273 2290 2641 4053 4178 4511 4654 4801 4850 5533 5593 6216 7214 7824 7844 8498 8522 8552 8563 8743 9124 9220 9622 9718 9882-9883 9885 9891 10111 10200 10280 10380-10381 10398 10515 10612 10628-10629 10674 10705 10739-10740 10987 11112 11377 11396 11832 11944 12306 13316 13426 16696 17234 17350 17398 17499 18069 18071 18173 18775 18779 18781 18800 18854 18932 19108 19227 19487 19489 19508 19537-19538 19618 19696 19749 19939 19981 19996 20031 20040 20279 20417 27719 28458 28617 29973 31688 48880 49121 49150https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/618/A121?format=asciiOpticaldefaultJ/A+A/618/A121/table1Disk galaxies from the CALIFA samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGalaxyGalaxy namemeta.id;meta.maincharNbinNumber of radial bins in anisotropy profilemeta.numberintB05h? Azimuthal anisotropy (at R=h/2)stat.fit.paramfloatnullablee_B05h? Error on azimuthal anisotropy (at R=h/2)stat.errorfloatnullableB1h? Azimuthal anisotropy at R=hstat.fit.paramfloatnullablee_B1h? Error on azimuthal anisotropy at R=hstat.errorfloatnullableB2h? Azimuthal anisotropy at R=2hstat.fit.paramfloatnullablee_B2h? Error on azimuthal anisotropy at R=2hstat.errorfloatnullableBre? Azimuthal anisotropy at R=Restat.fit.paramfloatnullablee_Bre? Error on azimuthal anisotropy at R=Restat.errorfloatnullableBmedMedian azimuthal anisotropy from profilestat.fit.paramfloate_BmedError on median azimuthal anisotropystat.errorfloatSimbadNameSimbad column added by the CDSmeta.idcharnullableNEDNED column added by the CDSmeta.ref.urlchar_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.main