Thin disk kinematics from RAVE and the solar motion

TL;DR

This study analyzes the kinematics of the Milky Way's thin disk using RAVE data, disentangling it from the thick disk to examine velocity dispersions and solar motion relative to the local standard of rest.

Contribution

A new statistical method to separate thin and thick disk populations in RAVE data and detailed analysis of thin disk kinematics around the solar neighborhood.

Findings

Velocity dispersion trends in the thin disk are mapped above and below the Galactic plane.

The solar motion relative to the local standard of rest is refined using the thin disk sample.

Velocity components and dispersions are characterized within 2 kpc of the Sun.

Abstract

Aims. We study the Milky Way thin disk with the Radial Velocity Experiment (RAVE) survey. We consider the thin and thick disks as different Galactic components and present a technique to statistically disentangle the two populations. Then we focus our attention on the thin disk component. Methods. We disentangle the thin disk component from amixture of the thin and thick disks using a data set providing radial velocities, proper motions, and photometrically determined distances. Results. We present the trend of the velocity dispersions in the thin disk component of the Milky Way (MW) in the radial direction above and below the Galactic plane using data from the RAdial Velocity Experiment (RAVE). The selected sample is a limited subsample from the entire RAVE catalogue, roughly mapping up to 500 pc above and below the Galactic plane, a few degrees in azimuthal direction and covering a radial extension of 2.0 kpc around the solar position. The solar motion relative to the local standard of rest is also re-determined with the isolated thin disk component. Major results are the trend of the velocity mean and dispersion in the radial and vertical direction. In addition the azimuthal components of the solar motion relative to the local standard of rest and the velocity dispersion are discussed.