Wide Twin Binaries are Extremely Eccentric: Evidence of Twin Binary Formation in Circumbinary Disks

  title={Wide Twin Binaries are Extremely Eccentric: Evidence of Twin Binary Formation in Circumbinary Disks},
  author={Hsiang-Chih Hwang and Kareem El-Badry and Hans–Walter Rix and Chris Hamilton and Yuan-Sen Ting and Nadia L. Zakamska},
  journal={The Astrophysical Journal Letters},
The Gaia mission recently revealed an excess population of equal-mass “twin” wide binaries, with mass ratio q ≳ 0.95, extending to separations of at least 1000 au. The origin of this population is an enigma: Twin binaries are thought to form via correlated accretion in circumbinary disks, but the typical observed protostellar disks have radii of ∼100 au, far smaller than the separations of the widest twins. Here, we infer the eccentricity distribution of wide twins from the distribution of… 


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On the Phase-mixed Eccentricity and Inclination Distributions of Wide Binaries in the Galaxy
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    The Astrophysical Journal Letters
  • 2022
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