A Spectroscopic Orbit for Regulus

  title={A Spectroscopic Orbit for Regulus},
  author={Douglas R. Gies and Sergio B. Dieterich and Noel D. Richardson and Adric R. Riedel and B. L. Team and Harold A. Mcalister and William G. Bagnuolo, Jr. and Erika D. Grundstrom and Stanislav {\vS}tefl and Th. Rivinius and Dietrich Baade},
  journal={The Astrophysical Journal Letters},
  pages={L117 - L120}
We present a radial velocity study of the rapidly rotating B star Regulus that indicates the star is a single-lined spectroscopic binary. The orbital period (40.11 days) and probable semimajor axis (0.35 AU) are large enough that the system is not interacting at present. However, the mass function suggests that the secondary has a low mass (M2 > 0.30 M☉), and we argue that the companion may be a white dwarf. Such a star would be the remnant of a former mass donor that was the source of the… 

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