Old Puzzle, New Insights: A Lithium-rich Giant Quietly Burning Helium in Its Core

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

About 1% of giant stars have been shown to have large surface Li abundances, which is unexpected according to standard stellar evolution models. Several scenarios for lithium production have been proposed, but it is still unclear why these Li-rich giants exist. A missing piece in this puzzle is the knowledge of the exact stage of evolution of these stars. Using low-and-high-resolution spectroscopic observations, we have undertaken a survey of lithium-rich giants in the Kepler field. In this Letter, we report the finding of the first confirmed Li-rich core-helium-burning giant, as revealed by asteroseismic analysis. The evolutionary timescales constrained by its mass suggest that Li production most likely took place through non-canonical mixing at the RGB tip, possibly during the helium flash.

Detaljer

Författare
  • V. Silva Aguirre
  • Gregory Ruchti
  • S. Hekker
  • S. Cassisi
  • J. Christensen-Dalsgaard
  • A. Datta
  • A. Jendreieck
  • J. Jessen-Hansen
  • A. Mazumdar
  • B. Mosser
  • D. Stello
  • P. G. Beck
  • J. de Ridder
Enheter & grupper
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Astronomi, astrofysik och kosmologi

Nyckelord

Originalspråkengelska
ArtikelnummerL16
TidskriftAstrophysical Journal Letters
Volym784
Utgåva nummer1
StatusPublished - 2014
PublikationskategoriForskning
Peer review utfördJa