BINARY CEPHEIDS: SEPARATIONS AND MASS RATIOS IN 5 M☉ BINARIES

@article{Evans2013BINARYCS,
  title={BINARY CEPHEIDS: SEPARATIONS AND MASS RATIOS IN 5 M☉ BINARIES},
  author={Nancy Remage Evans and Howard E. Bond and Gail H. Schaefer and Brian D. Mason and Margarita Karovska and Evan Tingle},
  journal={The Astronomical Journal},
  year={2013},
  volume={146}
}
Deriving the distribution of binary parameters for a particular class of stars over the full range of orbital separations usually requires the combination of results from many different observing techniques (radial velocities, interferometry, astrometry, photometry, direct imaging), each with selection biases. However, Cepheids—cool, evolved stars of ∼5 M☉—are a special case because ultraviolet (UV) spectra will immediately reveal any companion star hotter than early type A, regardless of the… 

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