Discovery of Nine Super Li-rich Unevolved Stars from the LAMOST Survey

Abstract

Based on the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) medium-resolution spectroscopic survey (MRS), we report the discovery of nine super Li-rich unevolved stars with A(Li) $>$ 3.8 dex. These objects show unusually high levels of lithium abundances up to three times higher than the meteoritic value of 3.3 dex, which indicates that they must have experienced a history of lithium enrichment. It is found that seven of our program stars are fast rotators with $vsini>9$ km\,s${}^{-1}$, which suggests that the accretion of circumstellar matter may be the main contributor to the lithium enhancement of these unevolved stars, however, other sources cannot be excluded.

10 pages, 3 figures

References in corpus (19)

• Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
• The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms
• The Radial Velocity Experiment (RAVE): Fifth Data Release
• Li abundances in F stars: planets, rotation and galactic evolution
• Explosive lithium production in the classical nova V339 Del (Nova Delphini 2013)
• Observable Signatures of Planet Accretion in Red Giant Stars I: Rapid Rotation and Light Element Replenishment
• A Map of Dust Reddening to 4.5 kpc from Pan-STARRS1
• Gaia EDR3 Reveals the Substructure and Complicated Star Formation History of the Greater Taurus-Auriga Star Forming Complex
• Overview of the LAMOST survey in the first decade
• 3D NLTE spectral line formation of lithium in late-type stars
• The AMBRE Project: Constraining the lithium evolution in the Milky Way
• The Gaia-ESO Survey: Galactic evolution of lithium from iDR6
• Enormous Li-enhancement preceding red giant phases in low-mass stars in the Milky Way halo
• Light Elements in the Universe
• The Gaia-ESO Survey: Galactic evolution of lithium at high metallicity
• Supernova Neutrino Process of Li and B Revisited
• Data-driven spectroscopic estimates of absolute magnitude, distance and binarity -- method and catalog of 16,002 O- and B-type stars from LAMOST
• The Lithium Abundances from the Large Sky Area Multi-object Fiber Spectroscopic Telescope Medium-resolution Survey. I. The Method
• The behaviour of lithium at high metallicity in the Milky Way -- Selection effects in the samples and the possible role of atomic diffusion

Cited by in corpus (3)

• Many Roads Lead to Lithium: Formation Pathways For Lithium-Rich Red Giants
• Convective Mixing: The Formation Channel of Li-rich Giants
• Unevolved Li-rich stars at low metallicity: a possible formation pathway through novae