Lithium Enrichment Signatures of Planetary Engulfment Events in Evolved Stars

  title={Lithium Enrichment Signatures of Planetary Engulfment Events in Evolved Stars},
  author={Melinda Soares-Furtado and Matteo Cantiello and Morgan MacLeod and Melissa K. Ness},
  journal={The Astronomical Journal},
Planetary engulfment events have long been proposed as a lithium (Li) enrichment mechanism contributing to the population of Li-rich giants (A(Li) ≥ 1.5 dex). Using MESA stellar models and A(Li) abundance measurements obtained by the GALAH survey, we calculate the strength and observability of the surface Li enrichment signature produced by the engulfment of a hot Jupiter (HJ). We consider solar-metallicity stars in the mass range of 1–2 M ⊙ and the Li supplied by a HJ of 1.0 M J. We explore… 
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