Lithium in CEMP-no stars: A new constraint on the lithium depletion mechanism in the early universe

Abstract

Most of relatively warm, unevolved metal-poor stars ($T_{\mathrm{eff}}\gtrsim 5800\mathrm{K}$ and $[Fe/H]\lesssim -1.5$) exhibit almost constant lithium abundances, irrespective of metallicity or effective temperature, and thus form the so-called Spite plateau. This was originally interpreted as arising from lithium created by the Big Bang nucleosynthesis. Recent observations, however, have revealed that ultra metal-poor stars (UMP stars; $[Fe/H]<-4.0$) have significantly lower lithium abundances than that of the plateau. Since most of the UMP stars are CEMP-no stars, carbon-enhanced metal-poor stars with no excess of neutron-capture elements, a connection between the carbon enhancement and lithium depletion is suspected. A straightforward approach to this question is to investigate carbon-normal UMP stars. However only one object is known in this class. As an alternative, we have determined lithium abundances for two CEMP-no main-sequence turn-off stars with metallicities $[Fe/H]\sim -3.0$, where there are numerous carbon-normal stars with available lithium abundances that can be considered. Our 1D LTE analysis indicates that the two CEMP-no stars have lithium abundances that are consistent with values near the plateau, which suggests that carbon enhancement and lithium depletion are not directly related. Instead, our results suggest that extremely low iron abundance is a fundamental cause to depleted lithium in UMP stars.

arXiv comment27 pages, 8 figures, 5 tables, to appear Publication of Astronomical Society of Japan

References in corpus (75)

• The chemical composition of the Sun
• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Planck 2013 results. XVI. Cosmological parameters
• The Seventh Data Release of the Sloan Digital Sky Survey
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• The Tenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Apache Point Observatory Galactic Evolution Experiment
• The First Data Release (DR1) of the LAMOST general survey
• Nucleosynthetic signatures of the first stars
• SkyMapper and the Southern Sky Survey
• Near-Field Cosmology with Metal-Poor Stars
• The SEGUE Stellar Parameter Pipeline. I. Description and Initial Validation Tests
• Carbon Enhanced Metal-Poor Stars. I. Chemical Compositions of 26 Stars
• The Hamburg/ESO R-process Enhanced Star survey (HERES) II. Spectroscopic analysis of the survey sample
• A Search for Stars of Very Low Metal Abundance. VI. Detailed Abundances of 313 Metal-Poor Stars
• The Stellar Abundances for Galactic Archeology (SAGA) Database - Compilation of the Characteristics of Known Extremely Metal-Poor Stars
• A single low-energy, iron-poor supernova as the source of metals in the star SMSS J 031300.36-670839.3
• Updated Big Bang Nucleosynthesis confronted to WMAP observations and to the Abundance of Light Elements
• Stellar Iron Abundances: non-LTE Effects
• Detailed Abundances for 28 Metal-poor Stars: Stellar Relics in the Milky Way
• Formation of the First Stars
• Departures from LTE for neutral Li in late-type stars
• The Spite Lithium Plateau: Ultra-Thin but Post-Primordial
• CH in stellar atmospheres: an extensive linelist
• Signatures of intrinsic Li depletion and Li-Na anti-correlation in the metal-poor globular cluster NGC6397
• The metal-poor end of the Spite plateau. 1: Stellar parameters, metallicities and lithium abundances
• First stars XII. Abundances in extremely metal-poor turnoff stars,and comparison with the giants
• A holistic approach to carbon-enhanced metal-poor stars
• First stars VII. Lithium in extremely metal poor dwarfs
• The Most Metal-Poor Stars. IV. The Two Populations With [Fe/H] < -3.0
• HE1327-2326, an unevolved star with [Fe/H]<-5.0. I. A Comprehensive Abundance Analysis
• Is HE0107-5240 A Primordial Star? -- The Characteristics of Extremely Metal-Poor Carbon-Rich Stars --
• The evolution of the C/O ratio in metal-poor halo stars
• A Subaru/HDS study of Lead (Pb) abundances in eight s-process-element-rich, metal-poor stars
• Observational Constraints on First-Star Nucleosynthesis. I. Evidence for Multiple Progenitors of CEMP-no Stars
• TOPoS: II. On the bimodality of carbon abundance in CEMP stars. Implications on the early chemical evolution of galaxies
• Binarity in Carbon-Enhanced Metal-Poor stars
• High-Resolution Spectroscopy of Extremely Metal-Poor Stars from SDSS/SEGUE: I. Atmospheric Parameters and Chemical Compositions
• Lithium Abundances of Extremely Metal-Poor Turn-off Stars
• Production and evolution of Li, Be and B isotopes in the Galaxy
• HE 1327-2326, an unevolved star with [Fe/H]<-5.0. II. New 3D-1D corrected abundances from a VLT/UVES spectrum
• The role of binaries in the enrichment of the early Galactic halo. III. Carbon-enhanced metal-poor stars -- CEMP-s stars
• An Elemental Assay of Very, Extremely, and Ultra Metal-Poor Stars
• Standard big bang nucleosynthesis and primordial CNO Abundances after Planck
• Abundance Profiling of Extremely Metal-Poor Stars and Supernova Properties in the Early Universe
• Observational evidence for a broken Li Spite plateau and mass-dependent Li depletion
• Detailed analysis of Balmer lines in cool dwarf stars
• Halo Star Lithium Depletion
• Carbon-Enhanced Metal-Poor Stars. III. Main-Sequence Turn-Off Stars from the SDSS/SEGUE Sample
• Stellar Archaeology: a Keck Pilot Program on Extremely Metal- Poor Stars From the Hamburg/ESO Survey. III. The Lead (Pb) Star HE 0024-2523
• The Lithium Content of the Galactic Halo Stars
• Deriving Stellar Effective Temperatures of Metal-Poor Stars with the Excitation Potential Method
• A primordial star in the heart of the Lion
• The Stellar Abundances for Galactic Archaeology (SAGA) Database II - Implications for Mixing and Nucleosynthesis in Extremely Metal-Poor Stars and Chemical Enrichment of the Galaxy
• First stars X. The nature of three unevolved Carbon-Enhanced Metal-Poor stars
• The role of binaries in the enrichment of the early Galactic halo. II. Carbon-Enhanced Metal-Poor Stars - CEMP-no stars
• Chemical Abundances of the Milky Way Thick Disk and Stellar Halo I.: Implications of [alpha/Fe] for Star Formation Histories in Their Progenitors
• CS22964-161: A Double-Lined Carbon- and s-Process-Enhanced Metal-Poor Binary Star
• Three carbon-enhanced metal-poor dwarf stars from the SDSS - Chemical abundances from CO^5BOLD 3D hydrodynamical model atmospheres
• Exploring the Origin of Lithium, Carbon, Strontium and Barium with four new Ultra Metal-Poor Stars
• A Search for Nitrogen-Enhanced Metal-Poor Stars
• The first stars: CEMP--no stars and signatures of spinstars
• The Stellar Abundances for Galactic Archaeology (SAGA) Database III - Analysis of Enrichment Histories for Elements and Two Modes of Star Formation during the Early Evolution of Milky Way
• From First Stars to the Spite Plateau: a Possible Reconciliation of Halo Stars Observations with Predictions from Big Bang Nucleosynthesis
• The Most Metal-Poor Stars. I. Discovery, Data, and Atmospheric Parameters
• Lithium abundances in CEMP stars
• Lithium-Rich Giants in Globular Clusters
• The Oxygen Abundance of HE 1327-2326
• Stellar Yields of Rotating First Stars. I. Yields of Weak Supernovae and Abundances of Carbon-enhanced Hyper Metal Poor Stars
• The effects of thermohaline mixing on low-metallicity asymptotic giant branch stars
• High-resolution spectroscopic studies of ultra metal-poor stars found in LAMOST survey
• Rapid rotation of ultra-Li-depleted halo stars and their association with blue stragglers
• Binary Blue Metal-Poor Stars: Evidence for AGB Mass Transfer
• Impact of granulation effects on the use of Balmer lines as temperature indicators
• Chemical Abundances of the Outer Halo Stars in the Milky Way
• G64-12 and G64-37 are Carbon-Enhanced Metal-Poor Stars

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• Four-hundred Very Metal-Poor Stars Studied with LAMOST and Subaru. II. Elemental abundances
• Binarity among CEMP-no stars: an indication of multiple formation pathways?
• Back to the Lithium Plateau with J0023+0307 with [Fe/H]<-6
• Enormous Li-enhancement preceding red giant phases in low-mass stars in the Milky Way halo
• The value-added catalogue for LAMOST DR8 low-resolution spectra
• The Most Metal-Poor Stars. V. The CEMP-no Stars in 3D and Non-LTE
• High-resolution spectroscopy of extremely metal-poor stars from SDSS/SEGUE. III. Unevolved Stars with $[Fe/H]\lesssim -3.5$
• Fingerprint of the first stars: multi-enriched extremely metal-poor stars in the TOPoS survey
• The Pristine survey -- XV. A CFHT ESPaDOnS view on the Milky Way halo and disc populations
• On the 12C/13C isotopic ratio at the dawn of chemical evolution
• The extreme CNO-enhanced composition of the primitive iron-poor dwarf star J0815+4729
• The ${}^6$Li/${}^7$Li isotopic ratio in the metal-poor binary CS22876--032
• Accurate effective temperature from H$\alpha$ profiles
• A Critique of the Spite Plateau, and the Astration of Primordial Lithium
• The metal-poor end of the Spite plateau. II. Detailed chemical investigation
• Matter accretion in metal-poor stars down to extremely metal-poor stars and the lithium problem
• Explaining the ${}^{12}\text{C}{/}^{13}\text{C}$ ratio in the Galactic halo: the contribution from shell mergers in primordial massive stars
• Lithium and Beryllium in One Solar Mass Stars
• Initial Li Abundances in the Protogalaxy and Globular Clusters Based upon the Chemical Separation and Hierarchical Structure Formation
• First Star Survivors as Metal-Rich Halo Stars that Experienced Supernova Explosions in Binary Systems
• Fuzzy Cluster Analysis: Application to Determining Metallicities for Very Metal-poor Stars