Galactic Rotation Parameters Based on Stars from Active Star-Forming Regions with Data from the Gaia DR2 Catalogue
O. I. Krisanova, V. V. Bobylev, A. T. Bajkova
Abstract
We have studied a sample of more than 25 000 young stars with proper motions and trigonometric parallaxes from the Gaia DR2 catalogue. The relative errors of their parallaxes do not exceed 10 $$\%$$ . The selection of stars belonging to active star-forming regions was made by Marton et al. based on data from the Gaia DR2 catalogue by invoking infrared measurements from the WISE and Planck catalogues. Low-mass T Tauri stars constitute the majority of sample stars. The following parameters of the angular velocity of Galactic rotation have been found from them: $$\Omega_{0}=28.40\pm 0.11$$ km s $${}^{-1}$$ kpc $${}^{-1}$$ , $$\Omega^{\prime}_{0}=-3.933\pm 0.033$$ km s $${}^{-1}$$ kpc $${}^{-2}$$ , and $$\Omega^{\prime\prime}_{0}=0.804\pm 0.040$$ km s $${}^{-1}$$ kpc $${}^{-3}$$ . The Oort constants are $$A=15.73\pm 0.32$$ km s $${}^{-1}$$ kpc $${}^{-1}$$ and $$B=-12.67\pm 0.34$$ km s $${}^{-1}$$ kpc $${}^{-1}$$ , while the circular rotation velocity of the solar neighborhood around the Galactic center is $$V_{0}=227\pm 4$$ km s $${}^{-1}$$ for the adopted Galactocentric distance of the Sun $$R_{0}=8.0\pm 0.15$$ kpc.