The Nearest Discovered Black Hole Is Likely Not in a Triple Configuration

  title={The Nearest Discovered Black Hole Is Likely Not in a Triple Configuration},
  author={Mohammadtaher Safarzadeh and Silvia Toonen and Abraham Loeb},
  journal={The Astrophysical Journal Letters},
HR 6819 was recently claimed to be a hierarchical triple system of a Be star in a wide orbit around an inner binary system of a black hole (BH) and a B III type star. We argue that this system is unlikely to be a hierarchical triple for three reasons. (i) Given that this system is discovered in a magnitude-limited Bright Star Catalog, the expected number of such systems in the Milky Way (MW) amounts to about 104, while the estimate for the MW budget for such systems is between 102 and 103… 

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