The Spectroscopic Orbital Period of HD 45166

HD 45166 was selected as a candidate to the V Sagittae Class. It’s spectrum shows quite narrow emission lines of He, C, N, and O, possibly indicating a low inclination for the binary system. We performed high resolution and high stability Coude spectroscopy in order to search for low amplitude radial velocity variations. The orbital period determined from the radial velocity curve is 0.357 days, and the radial velocity semi amplitude is K=3.8 km/s. The system inclination (in degrees), determined from the mass function of the secondary star, is 0.7 < i < 1.0.