Lithium-Rich Field Giants in the Sloan Digital Sky Survey

Abstract

We present a search for post-main-sequence field stars in the Galaxy with atypically large lithium abundances. Using moderate-resolution spectra taken as part of the Sloan Digital Sky Survey, along with high-resolution followup spectroscopy from the Hobby-Eberly Telescope, we identify 23 post-turnoff stars with log epsilon(Li) greater than 1.95, including 14 with log epsilon(Li) > 2.3 and 8 with log epsilon(Li) > 3.0, well above the low level expected for evolved stars. Comparison with theoretical isochrones indicates that some of our Li-rich stars are affiliated with the upper red giant branch, the asymptotic giant branch and the red clump rather than the RGB bump, which is a challenge to existing models of Li production in evolved stars.

11 pages, MNRAS accepted

References in corpus (20)

• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• The 2.5 m Telescope of the Sloan Digital Sky Survey
• The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
• The SEGUE Stellar Parameter Pipeline. I. Description and Initial Validation Tests
• An extremely primitive halo star
• The SEGUE Stellar Parameter Pipeline. II. Validation with Galactic Globular and Open Clusters
• The SEGUE Stellar Parameter Pipeline. III. Comparison with High-Resolution Spectroscopy of SDSS/SEGUE Field Stars
• High-Resolution Spectroscopy of Extremely Metal-Poor Stars from SDSS/SEGUE: I. Atmospheric Parameters and Chemical Compositions
• Complexity on Small Scales III: Iron and alpha Element Abundances in the Carina Dwarf Spheroidal Galaxy
• The SEGUE Stellar Parameter Pipeline. IV. Validation with an Extended Sample of Galactic Globular and Open Clusters
• Multi-Element Abundance Measurements from Medium-Resolution Spectra. IV. Alpha Element Distributions in Milky Way Dwarf Satellite Galaxies
• Observable Signatures of Planet Accretion in Red Giant Stars I: Rapid Rotation and Light Element Replenishment
• A new abundance scale for the globular cluster 47 Tuc
• Metal-Poor Lithium-Rich Giants in the Radial Velocity Experiment Survey
• Deep Mixing and Metallicity: Carbon Depletion in Globular Cluster Giants
• Lithium-rich giants in the Galactic thick disk
• The Hobby-Eberly Telescope "Chemical Abundances of Stars in the Halo" (CASH) Project. I. The Lithium-, s-, and r-Enhanced Metal-Poor Giant HKII 17435-00532
• Lithium abundances along the RGB: FLAMES-GIRAFFE spectra of a large sample of low-mass Bulge stars
• Discovery of Super-Li Rich Red Giants in Dwarf Spheroidal Galaxies
• A New Twist In the Evolution of Low-Mass Stars

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• VLT/FLAMES high-resolution chemical abundances in Sculptor: a textbook dwarf spheroidal galaxy
• On Lithium-Rich Red Giants. I. Engulfment of Sub-Stellar Companions
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• Lithium-Rich Giants in Globular Clusters
• Old puzzle, new insights: a lithium rich giant quietly burning helium in its core
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• Lithium-rich Giants in LAMOST Survey. I. The Catalog
• Most Lithium-rich Low-mass Evolved Stars Revealed as Red Clump stars by Asteroseismology and Spectroscopy
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• Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era
• Survey of Li-rich giants among Kepler and LAMOST fields: Determination of Li-rich giants Evolutionary Phase
• Enormous Li-enhancement preceding red giant phases in low-mass stars in the Milky Way halo
• The Penn State - Torun Centre for Astronomy Planet Search stars. II. Lithium abundance analysis of the Red Giant Clump sample
• The GALAH survey: A census of lithium-rich giant stars
• A super lithium-rich red-clump star in the open cluster Trumpler 5
• Lithium Enrichment Signatures of Planetary Engulfment Events in Evolved Stars
• On Infrared Excesses Associated With Li-Rich K Giants
• The Gaia-ESO Survey: properties of newly discovered Li-rich giants
• TAPAS - Tracking Advanced Planetary Systems with HARPS-N. II. Super Li-rich giant HD 107028
• Two new Super Li-rich core He-burning giants: A new twist to the long tale of Li enhancement in K giants
• Far-infrared study of K giants in the solar neighborhood: Connection between Li enrichment and mass-loss
• WIYN Open Cluster Study: The Old Open Cluster, NGC 188, and a Re-evaluation of Lithium-Richness Among Red Giants
• Spectroscopic study of two new super Li rich red clump K giants
• On the serendipitous discovery of a Li-rich giant in the globular cluster NGC 362
• On the observational characteristics of lithium-enhanced giant stars in comparison with normal red giants
• High-resolution spectroscopic analysis of a large sample of Li-rich giants found by LAMOST
• Many Roads Lead to Lithium: Formation Pathways For Lithium-Rich Red Giants
• Hydrodynamics and survivability during post-main-sequence planetary engulfment
• Lithium abundances in giants as a function of stellar mass: An evidence for He-flash as the source of Li enhancement in low mass giants
• Li-rich K giants, dust excess, and binarity
• New determination of abundances and stellar parameters for a set of weak G-band stars
• Li-rich Giants in LAMOST Survey. III. The statistical analysis of Li-rich giants
• The Gaia-ESO Survey: Inhibited extra mixing in two giants of the open cluster Trumpler 20?
• Lithium abundances and asteroseismology of red giants: understanding the evolution of lithium in giants based on asteroseismic parameters
• Super lithium-rich K giant with low ${}^{12}\mathrm{C}$ to ${}^{13}\mathrm{C}$ ratio
• HD 16771: A lithium-rich giant in the red-clump stage
• Li-rich and super Li-rich giants produced by element diffusion
• Exploring the SDSS Dataset with Linked Scatter Plots: I. EMP, CEMP, and CV Stars
• Are Lithium-Rich Giants Binaries? A Radial Velocity Variability Analysis of 1,400 Giants
• Li-rich Giants Identified from LAMOST DR8 Low-Resolution Survey
• Hot Jupiter engulfment by a red giant in 3D hydrodynamics
• LAMOST/HRS Spectroscopic Analysis of Two New Li-rich Giants
• On Lithium-6 as diagnostic of the lithium-enrichment mechanism in red giants
• The true nature of HE0057-5959, the most metal-poor Li-rich star
• Discovery of a Metal-Poor Red Giant Star with the Highest Ultra-Lithium Enhancement
• A Search for Candidate Li-Rich Giant Stars in SDSS DR10
• Stellar parameters for stars of the CoRoT exoplanet field
• Studying Young Stars with Large Spectroscopic Surveys
• Mass Loss Rates of Li-rich AGB/RGB Stars