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Related papers: Distribution functions for the Milky Way

200 papers

The outer parts of the Milky Way's disc are significantly out of equilibrium. Using only distances and proper motions of stars from Gaia's Early Data Release 3, in the range |b|<10{\deg}, 130{\deg}<l<230{\deg}, we show that for stars in the…

In this paper, we investigate some chemokinematical properties of the Milky Way disk, by using a sample composed by 424 late-type dwarfs. We show that the velocity dispersion of a stellar group correlates with the age of this group,…

Astrophysics · Physics 2009-11-10 H. J. Rocha-Pinto , C. Flynn , J. Scalo , J. Hanninen , W. J. Maciel , G. Hensler

We perform numerical simulations of a stellar galactic disk with initial conditions chosen to represent an unrelaxed population which might have been left following a merger. Stars are unevenly distributed in radial action angle, though the…

Astrophysics of Galaxies · Physics 2009-11-13 I. Minchev , A. C. Quillen , M. Williams , K. C. Freeman , J. Nordhaus , A. Siebert , O. Bienayme

A seven-parameter distribution function (DF) is fitted to $20\,000$ RR-Lyrae stars for which only astrometric data are available. The observational data are predicted by the DF in conjunction with the gravitational potential of a…

Astrophysics of Galaxies · Physics 2022-01-05 Chengdong Li , James Binney

Proper motions for several Milky Way dwarf spheroidal (dSph) galaxies have been determined using both ground and space-based imaging. These measurements require long baselines and repeat observations and typical errors are of order ten…

Astrophysics · Physics 2009-11-13 Manoj Kaplinghat , Louis E. Strigari

In earlier papers in this series we determined the intrinsic stellar disc kinematics of fifteen intermediate to late type edge-on spiral galaxies using a dynamical modeling technique. From the photometry we find that intrinsically more…

Astrophysics · Physics 2009-11-10 M. Kregel , P. C. van der Kruit , K. C. Freeman

We present a fully consistent evolutionary disc model of the solar cylinder. The model is based on a sequence of stellar sub-populations described by the star formation history (SFR) and the dynamical heating law (given by the age-velocity…

Astrophysics of Galaxies · Physics 2010-11-23 A. Just , H. Jahreiss

The aim of the analysis of data from the Gaia Space Observatory is to obtain kinematic parameters of the collective motion of stars in a part of our galaxy. This research is based on a statistical analysis of the motion of {$55,038,539$}…

Astrophysics of Galaxies · Physics 2025-02-18 Petr Zavada , Karel Píška

Action-based dynamical modelling, using stars as dynamical tracers, is an excellent diagnostic to estimate the underlying axisymmetric matter distribution of the Milky Way. However, the Milky Way's bar causes non-axisymmetric resonance…

Astrophysics of Galaxies · Physics 2023-06-27 Soumavo Ghosh , Wilma H. Trick , Gregory M. Green

We construct a new family of models of our Galaxy in which dark matter and disc stars are both represented by distribution functions that are analytic functions of the action integrals of motion. The potential that is self-consistently…

Astrophysics of Galaxies · Physics 2016-12-14 David R. Cole , James Binney

Stellar ages are a crucial component to studying the evolution of the Milky Way. Using Gaia DR2 distance estimates, it is now possible to estimate stellar ages for a larger volume of evolved stars through isochrone matching. This work…

We study the velocity distribution of Milky Way disk stars in a kiloparsec-sized region around the Sun, based on ~ 2 million M-type stars from DR7 of SDSS, which have newly re-calibrated absolute proper motions from combining SDSS positions…

A suite of vast stellar surveys mapping the Milky Way, culminating in the Gaia mission, is revolutionizing the empirical information about the distribution and properties of stars in the Galactic stellar disk. We review and lay out what…

Astrophysics of Galaxies · Physics 2013-12-04 Hans-Walter Rix , Jo Bovy

The mass distribution of the Galactic disk is constructed from the terminal velocity curve and the mass discrepancy-acceleration relation. Mass models numerically quantifying the detailed surface density profiles are tabulated. For $R_0 =…

Astrophysics of Galaxies · Physics 2016-01-13 Stacy S. McGaugh

Some formulae are presented for finding two-integral distribution functions (DFs) which depends only on the two classical integrals of the energy and the magnitude of the angular momentum with respect to the axis of symmetry for stellar…

Mathematical Physics · Physics 2007-08-28 Zhenglu Jiang , Leonid Ossipkov

The data obtained by the recent modern sky surveys enable detailed studies of the stellar distribution in the multi-dimensional space spanned by spatial coordinates, velocity and metallicity, from the solar neighborhood all the way out to…

Astrophysics · Physics 2009-11-13 S. Loebman , R. Roskar , Z. Ivezic

We present the derivation of distribution functions for the first four members of a family of disks, previously obtained in (MNRAS, 371, 1873, 2006), which represent a family of axially symmetric galaxy models with finite radius and well…

Astrophysics · Physics 2016-07-07 Guillermo A. González , Juan F. Pedraza , Javier Ramos-Caro

We investigate the kinematic parameters of the Milky Way disc using the RAVE and GCS stellar surveys. We do this by fitting a kinematic model to the data taking the selection function of the data into account. For stars in the GCS we use…

The Faraday dispersion function (FDF), which can be derived from an observed polarization spec- trum by Faraday rotation measure synthesis, is a profile of polarized emissions as a function of Faraday depth. We study intrinsic FDFs along…

Astrophysics of Galaxies · Physics 2015-06-22 Shinsuke Ideguchi , Yuichi Tashiro , Takuya Akahori , Keitaro Takahashi , Dongsu Ryu

A convenient representation of the structure of the large-scale galactic magnetic field is required for the interpretation of polarization data in the sub-mm and radio ranges, in both the Milky Way and external galaxies. We develop a simple…

Astrophysics of Galaxies · Physics 2019-03-14 Anvar Shukurov , Luiz Felippe S. Rodrigues , Paul J. Bushby , James Hollins , Jorg P. Rachen