J/ApJS/258/9 Stellar population parameters from LAMOST DR7 (Wang+, 2022)
Stellar populations of galaxies in the LAMOST spectral survey.
Wang L.-L., Shen S.-Y., Luo A.-L., Yang G.-J., Gai N., Tang Y.-K.,
Wang M.-X., Qin Li, Han J.-S., Rong L.-X.
<Astrophys. J. Suppl. Ser., 258, 9 (2022)>
=2022ApJS..258....9W 2022ApJS..258....9W
ADC_Keywords: Spectra, optical; Surveys; Redshifts; Stars, ages; Abundances
Keywords: Galaxies ; Stellar populations ; Spectroscopy ; Catalogs
Abstract:
We first derive the stellar population properties: age and metallicity
for ∼43000 low redshift galaxies in the DR7 of the Large Sky Area
Multi-Object Fiber Spectroscopic Telescope (LAMOST) survey, which have
no spectroscopic observations in the Sloan Digital Sky Survey (SDSS).
We employ a fitting procedure based on the small-scale features of
galaxy spectra so as to avoid possible biases from the uncertain flux
calibration of the LAMOST spectroscopy. We show that our algorithm can
successfully recover the average age and metallicity of the stellar
populations of galaxies down to signal-to-noise ratio ≥5 through
testing on both mock galaxies and real galaxies comprising LAMOST and
their SDSS counterparts. We provide a catalog of the age and
metallicity for ∼43000 LAMOST galaxies online. As a demonstration of
the scientific application of this catalog, we present the Holmberg
effect on both age and metallicity of a sample of galaxies in galaxy
pairs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 72 42885 Catalogue of the stellar population parameters
for ∼43000 galaxies in LAMOST DR7.
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See also:
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
V/156 : LAMOST DR7 catalogs (Luo+, 2019)
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
J/ApJS/94/687 : Old stellar populations. V. (Worthey+, 1994)
J/A+AS/141/371 : Low-mass stars evolutionary tracks (Girardi+, 2000)
J/AJ/127/1883 : Merging galaxies in SDSS EDR (Allam+, 2004)
J/MNRAS/371/703 : MILES library of empirical sp. (Sanchez-Blazquez+, 2006)
J/MNRAS/404/1639 : MILES models & new line index syst. (Vazdekis+, 2010)
J/other/RAA/15.1414 : E+A galaxy candidates in LAMOST DR2 (Yang+, 2015)
J/AJ/151/24 : LAMOST quasar survey: QSOs from the DR1 (Ai+, 2016)
J/ApJS/222/16 : Herschel obs. of major-merger pairs of gal. (Cao+, 2016)
J/other/RAA/16.C7 : LAMOST-SDSS galaxy pairs (Shen+, 2016)
J/MNRAS/474/1873 : Classification of LAMOST DR4 galaxies (Wang+, 2018)
J/ApJS/234/5 : LaCoSSPAr in the Southern Galactic Cap. I. (Yang+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- obsid [102096/746812078] LAMOST DR7 spectral
observation identifier
11- 21 F11.7 deg RAdeg Right Ascension, decimal degrees (J2000)
23- 32 F10.7 deg DEdeg [-9/78] Declination, decimal degrees (J2000)
34- 41 F8.6 --- zspec [0/0.4] spectroscopic redshift
43- 48 F6.2 --- SNr [5/224] Signal-to-noise ratio in the r-band
50- 58 F9.3 mag rmag [9.8/31.9]?=-9999 Petrosian magnitude in r band (1)
60- 65 F6.3 [yr] logAge [7.8/10.2] log of mean stellar age
67- 72 F6.3 [Sun] [M/H] [-1.71/0.22] lof of mean stellar metallicity, Z
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Note (1): Petrosian magnitude in r-band cross-matched with the photometric
catalog of SDSS.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 28-Apr-2022