Evaluation of the Gaia astrometric solution. Horizontal dashed lines indicate the limits of errors in PMs (0.5 mas yr⁻¹) and parallax (0.5 mas). From left to right: Gaia PMs in Right Ascension, Declination, and parallax versus their errors are shown. Gaussian profiles were fitted in each panel and ±5σ were calculated (vertical dashed lines). For final selected targets (red) based on the parallax, except an adopted Gaussian fitting, an additional elliptical constraint was also applied with the 5σ limits of Gaussian profiles in PM_RA and PM_Dec (based on blue targets in the first two panels), which are considered as the primary and secondary radii, respectively. Green contours show the number density in each diagram.