The Gaia -ESO Survey: Galactic evolution of lithium at high metallicity

Research output: Contribution to journalReview article

Abstract

Context. Reconstructing the Galactic evolution of lithium (Li) is the main tool used to constrain the source(s) of Li enrichment in the Galaxy. Recent results have suggested a decline in Li at supersolar metallicities, which may indicate reduced production. Aims. We exploit the unique characteristics of the Gaia-ESO Survey open star cluster sample to further investigate this issue and to better constrain the evolution of Li at high metallicity. Methods. We trace the upper envelope of Li abundance versus metallicity evolution using 18 clusters and considering members that should not have suffered any Li depletion. Results. At variance with previous claims, we do not find any evidence of a Li decrease at high metallicity. The most metal-rich clusters in the sample ([Fe/H] = ∼0.3) actually show the highest Li abundances, with A(Li) > 3.4. Our results clearly show that previous findings, which were based on field stars, were affected by selection effects. The metal-rich population in the solar neighbourhood is composed of relatively old and cool stars that have already undergone some Li depletion; hence, their measured Li does not represent the initial interstellar medium abundance, but a lower limit to it.

Details

Authors
  • S. Randich
  • L. Pasquini
  • E. Franciosini
  • L. Magrini
  • R. J. Jackson
  • R. D. Jeffries
  • V. D'Orazi
  • D. Romano
  • N. Sanna
  • G. Tautvaišienė
  • M. Tsantaki
  • N. J. Wright
  • G. Gilmore
  • A. Bragaglia
  • E. Pancino
  • R. Smiljanic
  • A. Bayo
  • G. Carraro
  • A. Gonneau
  • A. Hourihane
  • L. Morbidelli
  • C. C. Worley
Organisations
External organisations
  • INAF - Osservatorio Astrofisico di Arcetri
  • European Southern Observatory
  • Keele University
  • INAF - Osservatorio Astronomico di Padova
  • INAF Istituto di Astrofisica Spaziale e Fisica Cosmica, Bologna
  • Vilnius University
  • University of Cambridge
  • Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences
  • University of Valparaíso
  • University of Padova
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Astronomy, Astrophysics and Cosmology

Keywords

  • Galaxy: abundances, Galaxy: evolution, Open clusters and associations: general, Stars: abundances
Original languageEnglish
Article number2038688
JournalAstronomy and Astrophysics
Volume640
Publication statusPublished - 2020
Publication categoryResearch
Peer-reviewedYes