Parameters of the Galactic Spiral Density Wave from Masers with Parallax Errors Less Than 10 %

Abstract

Abstract: We have studied the kinematics of Galactic masers and radio stars with measured VLBI trigonometric parallaxes and proper motions. We have considered masers with relative trigonometric parallax errors less than 10% and determined the Galactic rotation parameters from them. In particular, the linear rotation velocity of the Galaxy at the solar distance R0 has been found to be (Formula presented.) km s-1 (for the adopted (Formula presented.) kpc). We have performed a joint and separate spectral analysis of the radial, residual tangential, and vertical maser velocities. For example, from the vertical maser velocities we have estimated the velocity perturbation amplitude (Formula presented.) km s-1 with the wavelength (Formula presented.) kpc, arguing for the influence of the spiral density wave on the vertical stellar velocities. Based on 104 masers within 3 kpc of the Sun, as a result of the joint solution, we have estimated the radial, (Formula presented.) km s-1, and tangential, (Formula presented.), velocity perturbations, the perturbation wavelength (Formula presented.) kpc, and the Sun’s phase in the Galactic spiral density wave (Formula presented.). We have confirmed the presence of the Radcliffe wave in the spatial distribution of masers and radio stars belonging to the Local Arm.