An Ultra Metal-poor Star Near the Hydrogen-burning Limit

  title={An Ultra Metal-poor Star Near the Hydrogen-burning Limit},
  author={Kevin C. Schlaufman and Ian B. Thompson and Andrew R. Casey},
  journal={The Astrophysical Journal},
It is unknown whether or not low-mass stars can form at low metallicity. While theoretical simulations of Population III (Pop III) star formation show that protostellar disks can fragment, it is impossible for those simulations to discern if those fragments survive as low-mass stars. We report the discovery of a low-mass star on a circular orbit with orbital period P = 34.757 ± 0.010 days in the ultra metal-poor (UMP) single-lined spectroscopic binary system 2MASS J18082002–5104378. The… 

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