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arXiv · 1411.3548

Determination of the Solar Galactocentric distance from masers kinemics

A. T. Bajkova·V. V. Bobylev
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Abstract

We have determined the Galactic rotation parameters and the solar Galactocentric distance $R_0$ by simultaneously solving Bottlinger's kinematic equations using data on masers with known line-of-sight velocities and highly accurate trigonometric parallaxes and proper motions measured by VLBI. Our sample includes 93 masers spanning the range of Galactocentric distances R from 3 to 15 kpc. The solutions found are \Omega_0 = 29.7+/-0.5 km s^{-1} kpc^{-1}, \Omega'_0 = -4.20+/-0.11 km s^{-1} kpc^{-2}, \Omega"_0 =0.730+/-0.029 km s^{-1} kpc^{-3}, and R_0=8.03+/-0.12 kpc. In this case, the linear rotation velocity at the solar distance R_0 is V_0=238+/-6 km s^{-1}.

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A. T. Bajkova, V. V. Bobylev. 2014-11-13. Determination of the Solar Galactocentric distance from masers kinemics. https://doi.org/10.1515/astro-2017-0201

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