The spectroscopic orbit of the double-lined binary 29 Arietis.

Twenty radial velocities obtained with the radial-velocity spectrometer of the 1.2-m Dominion Astrophysical Observatory telescope at dispersions of 2.4 and 6.5 A/mm show the star 29 Ari to be double lined. The data determined a period of 19.3787 + or - 0.0005 d, a systematic velocity of the secondary of 8.95 + or - 0.40 km/s, and a primary to secondary luminosity ratio of 4.0, corresponding to a 1.51 m difference in the wavelength region observed (approximately B). A model for the system similar to those by Griffin et al. (1985) for Hyades binaries is made.