A Spectroscopic Orbit for Regulus

  title={A Spectroscopic Orbit for Regulus},
  author={D. Gies and S. Dieterich and N. Richardson and A. Riedel and B. Team and H. Mcalister and W. Bagnuolo and Jr. and E. Grundstrom and S. {\vS}tefl and T. Rivinius and D. Baade},
  journal={The Astrophysical Journal},
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… Expand

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