Duplicity in the solar neighborhood. I.

A new orbit has been determined for the double-line spectroscopic binary BY Draconis (HDE 234677) using measurements made with the photoelectric radial velocity spectrometer of Geneva Observatory. The radius of the primary, as deduced from the rotational velocity and an estimate of the mass, is between 1.2 and 1.4 solar radii. The large radius leads to the supposition that the primary is in a state of pre-main-sequence evolution. On the other hand, a significantly higher macroturbulence of 3.2 km/s would reduce the estimate for the radius and rotation by a factor of two. In this case, BY Dra would be located on the main sequence.