Orbital Elements of the double B star HR 2875

Abstract

Echelle spectroscopy has been obtained at Lick Observatory and at Mount Stromlo Observatory which reveals that the B star plus white dwarf system HR 2875 is actually a triple system comprised of the B3.5 primary, a B6 secondary and the white dwarf. Orbital parameters for the two B stars have been determined and indicate a period P =15.0811 days and an eccentricity e =0.68. The location of the white dwarf relative to the pair of B stars is unknown but may be sufficiently close to perturb their orbit. Further studies of the triple system are planned.