Kinematic properties of the Galactic thick disk from data from the RAVE DR4 catalog

Resumo

The analysis of the kinematic properties of the Galactic thick disk based on data from modern catalogs of stellar radial velocities and proper motions is presented. A new aspect of new determination of the kinematic characteristics of the thick disk is that the selected objects define this disk’s properties near the plane of symmetry. The velocity dispersion of stars in the Galactic thick disk in the radial direction and the direction of the Galactic rotation have been determined. The stellar-velocity distribution in the direction of the rotation is asymmetric. The parameters of this asymmetry have been determined, and the lag of the rotational velocity of the thick disk relative to objects in the thin disk estimated. The value of this “asymmetric drift,” about 20 km/s, suggests larger spatial scales for the kinematic characteristics in the radial direction for the Galactic thick disk than for the thin disk.