J/ApJ/914/116 Lithium abundances from LAMOST MRS. I. (Gao+, 2021)
The lithium abundances from the Large Sky Area Multi-Object Fiber Spectroscopic
Telescope Medium-Resolution Survey.
I. The method.
Gao Q., Shi J.-R., Yan H.-L., Li C.-Q., Chen T.-Y., Zhang J.-H., Liu S.,
Yan T.-S., Xie X.-J., Ding M.-Y., Zhang Y., Hou Y.-H.
<Astrophys. J., 914, 116-116 (2021)>
=2021ApJ...914..116G 2021ApJ...914..116G (SIMBAD/NED BibCode)
ADC_Keywords: Abundances; Spectra, optical
Keywords: Stellar abundances; Stellar evolution; Chemically peculiar stars
Abstract:
One of the purposes of taking spectra for millions of stars through
the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)
medium-resolution survey (MRS) is to obtain the elemental abundances,
so that one can trace the origin and evolution for the element of
interests. Lithium is one of such elements of great importance, which
exhibits many puzzling behaviors. Investigating the lithium abundances
to a uniquely large sample of stars is essential to understand its
origin and evolution. In this paper, we present the lithium abundances
obtained from the LAMOST MRS spectra calculated by the
template-matching method. Our data set consists of 294857 spectra that
corresponds to 165479 stars with a resolution power of
Δλ/λ∼7500. We compared the lithium abundances
derived from our work with those using the high-resolution spectra and
found a good consistence. The errors of lithium abundances are
discussed. Our results suggest that the distribution of lithium
abundances show two clear peaks at +2.6 and +1.0dex, respectively.
This sample is potentially important for investigating physical
mechanisms occurring inside stars that alter the surface lithium
abundance.
Description:
The LAMOST MRS spectra consist of the blue and red band, and the
wavelength ranges are 4950∼5350 and 6300∼6800Å, respectively. In
our study, the red-band spectra observed from September 2017 to June
2019 with a signal-to-noise ratio (S/N) higher than 10 have been
selected.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 103 294857 The information and resulting lithium abundances
of our sample
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See also:
III/218 : ELODIE archive (Prugniel+, 2001)
V/153 : LAMOST DR4 catalogs (Luo+, 2018)
V/156 : LAMOST DR7 catalogs (Luo+, 2019)
III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)
J/A+A/503/545 : EWs of Li, Na, Fe, Ca in NGC 6397 (Lind+, 2009)
J/A+A/522/A26 : Fe Abundances in metal-poor stars (Sbordone+ 2010)
J/ApJ/756/46 : Lithium abundances in HIP stars (Ramirez+, 2012)
J/A+A/576/A69 : Li abundances in F stars (Delgado Mena+, 2015)
J/AJ/151/144 : ASPCAP weights for APOGEE chemical elements (Garcia+, 2016)
J/A+A/595/A18 : Lithium abundances in AMBRE stars (Guiglion+, 2016)
J/AJ/153/128 : WOCS. LXXV. Hyades&Praesepe Lithium data (Cummings+, 2017)
J/A+A/610/A38 : Li enrichment histories of the thick/thin disc (Fu+, 2018)
J/AJ/155/138 : WOCS.LXXVI.Vel. & abund. in NGC2506 (Anthony-Twarog+, 2018)
J/A+A/615/A151 : Lithium abundances in 714 F & G dwarf stars (Bensby+, 2018)
J/MNRAS/478/4513 : GALAH Survey DR2 (Buder+, 2018)
J/MNRAS/484/4591 : The GALAH Survey lithium-strong KM dwarfs (Zerjal+, 2019)
J/AJ/158/163 : Li abundance values for stars in NGC6819 (Deliyannis+, 2019)
J/A+A/634/A130 : Lithium abund. in microlensed bulge dwarfs (Bensby+, 2020)
J/AJ/159/90 : Li, C and O abundances of FGK stars (Stonkute+, 2020)
J/MNRAS/506/150 : The GALAH+ Survey DR3 (Buder+, 2021)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- LAMOST LAMOST MRS identifier (JHHMMSS.ss+DDMMSS.s)
21- 29 I9 --- obsID [588902003/747816250] LAMOST obsID
31- 49 I19 --- GaiaDR2 Gaia DR2 identifier
51- 60 F10.6 deg RAdeg Right ascension (J2000)
62- 70 E9.6 deg DEdeg [-9.99/76.3] Declination (J2000)
72- 75 I4 K Teff [3515/7000] Effective temperature
77- 80 F4.2 [cm/s2] logg [0.07/4.97] Log of surface gravity
82- 86 F5.2 Sun [Fe/H] [-2.45/0.5] [Fe/H] abundance
88- 90 I3 --- S/N [10/999] Signal-to-noise ratio of the spectrum
92- 96 F5.2 --- A(Li) [-1.47/5.48] Lithium abundance
98- 101 F4.2 --- e_A(Li) [0.05/0.41] A(Li) uncertainty
103 A1 --- Ref Reference for stellar parameters Teff, logg
and [Fe/H] (1)
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Note (1): Reference as follows:
L = LASP; stellar parameters of LAMOST DR7: They were derived from the
LAMOST low-resolution spectra with the LAMOST Stellar Parameter Pipeline
(Luo+ 2015, V/146) using a template-matching method (267,962 occurrences);
A = APOGEE; stellar parameters of SDSS DR16: They were from the Apache
Point Observatory Galactic Evolution Experiment (APOGEE)-2/Sloan Digital
Sky Survey (SDSS-IV survey, Jonsson+ 2020, III/284 determined by the
APOGEE Stellar Parameter and Chemical Abundances Pipeline ASPCAP);
26,895 occurrences
See Section 2.2.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 12-Dec-2022