The distance to the Galactic center determined by G, K, and M stars

Abstract

The distance from the Sun to the center of the Galaxy R0 remains a fundamental parameter for Galactic structure. This study uses 105,275 G, K, and M stars of all luminosity classes with position, parallax, and proper motion taken from the Hipparcos catalog and radial velocities from the Wilson and Strasbourg Data Center catalogs. The nonlinear kinematical equations of condition are solved by the Nelder-Mead simplex algorithm and give R0=7.64±0.09kpc. At a confidence level of 90 % one can assert the randomness of the residuals and shows that the kinematical model yields satisfactory results.