3D test particle simulations of the Galactic disks. The kinematical effects of the bar

摘要

Aims: To study the imprints of a rotating bar on the kinematics of stars inthe thin and thick disks throughout the Galaxy. Methods: We perform testparticle numerical simulations of the thin and thick disks in a 3D Galacticpotential that includes a halo, a bulge, thin and thick disks, and a Ferrersbar. We analyze the resulting velocity distributions of populationscorresponding to both disks, for different positions in the Galaxy and fordifferent structural parameters of the bar. Results: We find that the velocitydistributions of the disks are affected by the bar, and that strong transienteffects are present for approximately 10 bar rotations after this is introducedadiabatically. On long (more realistic) timescales, the effects of the bar arestrong on the kinematics of thin disk stars, and weaker on those in the thickdisk, but in any case significant. Furthermore, we find that it is possible totrace the imprints of the bar also vertically and at least up to z ~ 1 kpc forthe thin disk and z ~ 2 kpc for the thick disk.