Absence of a metallicity effect for ultra-short-period planets

  title={Absence of a metallicity effect for ultra-short-period planets},
  author={Joshua N. Winn and Roberto Sanchis-Ojeda and Leslie A. Rogers and Erik A. Petigura and Andrew W. Howard and Howard T. Isaacson and Geoffrey W. Marcy and Kevin C. Schlaufman and Phillip A. Cargile and Leslie Hebb},
  journal={arXiv: Earth and Planetary Astrophysics},
Ultra-short-period (USP) planets are a newly recognized class of planets with periods shorter than one day and radii smaller than about 2 Earth radii. It has been proposed that USP planets are the solid cores of hot Jupiters that lost their gaseous envelopes due to photo-evaporation or Roche lobe overflow. We test this hypothesis by asking whether USP planets are associated with metal-rich stars, as has long been observed for hot Jupiters. We find the metallicity distributions of USP-planet and… Expand

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