Ultracool and Brown Dwarf Candidates Identified via CatWISE-2MASS-Gaia DR3

Ultracool and brown dwarf candidates (d 125 pc, b>8) were identified via multiband and astrometric data from CatWISE (W 1W 2), 2MASS (JHK s), and Gaia DR3 (G, G RP, pi, mu alpha, mu delta). N about 11.8 times 10 cubed candidates emerged once simultaneously constrained by color and absolute magnitude criteria (e.g., G-W 2 1.75(G-J)-2.25), whereby 350 sources are absent from the Gaia Ultracool Dwarf (UCD) catalog. Spectral types were approximated using a hybrid M G-M W 1 sigmoid that offers additional temperature coverage in certain cases. Subsequent efforts may focus on extending sampling to the deeper NIR VVVX footprint that partly encompasses the Galactic plane, and over the long-term spectroscopically (in)validating candidates missing from the Gaia UCD database.