Parameters of the Galactic Spiral Density Wave from Masers with Parallax Errors Less Than 10$$\boldsymbol{\%}$$

We have studied the kinematics of Galactic masers and radio stars with measured VLBI trigonometric parallaxes proper motions. considered relative parallax errors less than 10\% determined rotation parameters from them. In particular, linear velocity Galaxy at solar distance $R_0$ has been found to be $244.4\pm4.3$ km s$^{-1}$ (for adopted $R_0=8.1\pm0.1$ kpc). performed a joint separate spectral analysis radial, residual tangential, vertical maser velocities. For example, velocities we estimated perturbation amplitude $f_W=5.2\pm1.5$ wavelength $\lambda_W=2.6\pm0.7$ kpc, arguing for influence spiral density wave on stellar Based 104 within 3 kpc Sun, as result solution, $f_R=6.7\pm1.1$ s$^{-1}$, $f_\theta=2.6\pm1.2$ perturbations, $\lambda=2.1\pm0.3$ Sun's phase in $\chi_\odot=-148\pm15^\circ$. confirmed presence Radcliffe spatial distribution belonging Local Arm.