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Analysis of the three-dimensional stellar velocity field using vector spherical functions

Tsvetkov, A. S.; Vityazev, V. V.

We apply vector spherical functions to problems of stellar kinematics. Using these functions allows all of the systematic components in the stellar velocity field to be revealed without being attached to a specific physical model. Comparison of the theoretical decomposition coefficients of the equations for a particular kinematical model with obse…

Kinematics of Tycho-2 red giant clump stars

Bobylev, V. V.; Bajkova, A. T.; Gontcharov, G. A. +1 more

Based on the Ogorodnikov-Milne model, we analyze the proper motions of 95,633 red giant clump (RGC) stars from the Tycho-2 Catalogue. The following Oort constants have been found: A = 15.9 ± 0.2 km s-1 kpc-1 and B = -12.0±0.2 km s-1 kpc-1. Using 3632 RGC stars with known proper motions, radial velocities, and photometric distances, we show that, a…

Using the reduced proper motions of Tycho-2 stars with B-V from 0.75 to 1.25: Monte Carlo simulations

Gontcharov, G. A.

The stellar composition of the Tycho-2 Catalogue in the range B-V = 0{_·/ ^m }75-1{_·/ ^m }25 has been reproduced through Monte Carlo simulations. For young and old stars of the red giant clump (RGC), the red giant branch, subgiants, red dwarfs, and thick-disk giants, we have specified the distributions in c…