摘要：By combining our improved visual orbit with the last spectroscopic solution of the single-lined spectroscopicbinary, MCA 74 (ADS 16672Aa, Ab; HD 219834A), we derived its orbital solution to have a period of6.321 years. Using the Gaia parallax, a systemic mass of 1.87±0.09 and a mass ratio of q=0.725 wereobtained, which yielded individual masses of 1.07±0.06 and 0.80±0.04 for the main and thesecondary components, respectively. The mass and the absolute magnitude of +3.52 confirm that the primary is alate G5–G8 subgiant, while the same parameters of the secondary (Mv=+6.52) suggest that it is an early K2–K3dwarf.
关键词：astrometry;binaries: visual;stars: fundamental parameters
