J/ApJS/277/47 Metallicities for LAMOST LRS DR10 M dwarf stars (Zhang+, 2025)
Half a million M dwarf stars characterized using domain-adapted spectral
analysis.
Zhang S., Zhang H.-W., Ting Y.-S., Wang R., O'Briain T., Jones H.R.A.,
Homeier D., Luo A.-L.
<Astrophys. J. Suppl. Ser., 277, 47 (2025)>
=2025ApJS..277...47Z 2025ApJS..277...47Z
ADC_Keywords: Stars, M-type; Spectra, optical; Abundances; Radial velocities
Keywords: M dwarf stars ; Spectroscopy ; Fundamental parameters of stars ;
Catalogs
Abstract:
We present fundamental atmospheric parameters (Teff and logg) and
metallicities ([M/H]) for 507,513 M dwarf stars using low-resolution
spectra (R∼1800) from LAMOST DR10. By employing Cycle-StarNet, an
innovative domain adaptation approach, we successfully bridge the gap
between theoretical PHOENIX synthetic spectra and observed LAMOST
spectra, enabling parameter measurements even for lower
signal-to-noise (S/N) data (S/N>5). The fitting residual analysis
shows a reduction from 2.0 times to 1.68 times the flux uncertainty.
Comparing with available literature values, we find systematic offsets
and precisions of 12±70K in Teff, -0.04±0.17dex in logg, and
-0.06±0.20dex in [M/H]. The precision improves for higher-quality
spectra (S/N>50) to 47K, 0.12dex, and 0.14 dex respectively. The
metallicity consistency between wide binaries shows a scatter of
0.24dex, improving to 0.15dex at S/N>50. We provide a comprehensive
catalog including stellar parameters, spectral classifications,
activity indicators, and binary/variability flags, establishing a
resource for studies of the most numerous stellar population.
Description:
LAMOST, located at Xinglong Observatory in Hebei, China, is a 4m
reflecting Schmidt telescope equipped with active optics. Its
multiobject fiber spectroscopic system enables simultaneous
observations of 4000 celestial targets. As of 2022 June, LAMOST has
published the 10th data release with a total of over 22.29 million
spectra, consisting of 11.81 million low-resolution spectra and
10.48 million medium-resolution spectra. The low-resolution survey
covers a broad spectral range of 3700-9000Å with a resolution
R∼1800. In this data set, 818,686 low-resolution spectra are
classified as M-type dwarfs, as Figure 1 shows.
After applying selection criteria detailed in Sections 2 and 4, the
final catalog contains 507,513 objects, corresponding to 426,008
unique stars.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 174 507513 Value-added catalog
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See also:
B/sb9 : SB9: 9th Catalog of Spectroscopic Binary Orbits (Pourbaix+ 2004-2014)
III/198 : Palomar/MSU nearby star spectroscopic survey (Hawley+ 1997)
III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
V/122 : SB9: 9th Catalogue of Spectroscopic Binary Orbits (Pourbaix+ 2005)
VI/119 : High accuracy computed water line list - BT2 (Barber+, 2006)
V/152 : The DEBCat detached eclipsing binary catalogue (Southworth, 2015)
V/162 : LAMOST DR11 catalogs (Luo+, 2026)
J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)
J/AJ/128/426 : Subdwarfs in the SDSS (West+, 2004)
J/AJ/135/785 : SDSS-DR5 low-mass star spectroscopic sample (West+, 2008)
J/A+A/497/497 : Physical parameters from JHK flux (Gonzalez-Hernandez+, 2009)
J/AJ/141/97 : SDSS DR7 M dwarfs (West+, 2011)
J/other/RAA/11.924 : Atmospheric parameters for 771 stars (Wu+, 2011)
J/ApJ/748/93 : K-band spectra for 133 nearby M dwarfs (Rojas-Ayala+, 2012)
J/AJ/145/102 : Spectrosc. of M dwarfs in the northern sky (Lepine+, 2013)
J/AJ/145/52 : Abund. of late K and M dwarfs in binary systems (Mann+, 2013)
J/A+A/556/A15 : Effective temperature scale of M dwarfs (Rajpurohit+, 2013)
J/A+A/564/A90 : M subdwarfs VLT/UVES high res. spectra (Rajpurohit+, 2014)
J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)
J/ApJ/808/16 : Cannon: a new approach to determine abundances (Ness+, 2015)
J/A+A/585/A64 : New atmospheric param. of MILES cool stars (Sharma+, 2016)
J/ApJ/834/85 : Hα emission in nearby M dwarfs (Newton+, 2017)
J/ApJ/851/26 : Teff, metallicity & Ti abundance of M dwarfs (Veyette+, 2017)
J/ApJ/836/77 : A library of high-S/N opt. spectra of FGKM stars (Yee+, 2017)
J/A+A/615/A6 : Photospheric parameters of CARMENES stars (Passegger+, 2018)
J/A+A/620/A180 : Stellar properties of M dwarfs (Rajpurohit+, 2018)
J/A+A/612/A49 : 324 CARMENES M dwarfs velocities (Reiners+, 2018)
J/ApJS/243/2 : SiIV and NV absorption line SDSS quasar systems (Chen+, 2019)
J/AJ/157/63 : Radius relations for low-metallicity stars (Kesseli+, 2019)
J/ApJ/878/134 : HARPS & X-shooter sp. of Southern M dwarfs (Kuznetsov+ 2019)
J/A+A/627/A161 : CARMENES stars multiwavelength data (Passegger+, 2019)
J/ApJ/879/69 : The Payne applied to the APOGEE DR14 data set (Ting+, 2019)
J/ApJ/892/31 : Teff & metallicities of M dwarfs in APOGEE (Birky+, 2020)
J/AJ/159/30 : High proper-motion M-type stars sp. obs. (Hejazi+, 2020)
J/A+A/642/A121 : LHS1140 radial velocity data (Lillo-Box+, 2020)
J/ApJ/905/107 : Sp. activity indicators of TIC stars (Medina+, 2020)
J/MNRAS/506/150 : The GALAH+ Survey DR3 (Buder+, 2021)
J/AJ/161/172 : The Solar Neighborhood. XLVII. Mdwarfs (Dieterich+, 2021)
J/AJ/162/184 : APOGEE: Properties & RVel of binaries (Kounkel+, 2021)
J/A+A/649/A147 : Spectroscopic parameters for 313 M dwarfs (Sarmento+, 2021)
J/ApJ/908/131 : M-subdwarf research. II. Catalog (Zhang+, 2021)
J/ApJS/260/45 : Stellar param. of M-type stars from LAMOST DR8 (Ding+, 2022)
J/A+A/658/A115 : Proxima Cen ESPRESSO RV and FWHM (Faria+, 2022)
J/ApJ/927/122 : The local disk & halo. II. (Hejazi+, 2022)
J/A+A/660/A38 : Ultracool dwarfs with spectra in LAMOST DR7 (Wang+, 2022)
J/A+A/674/A22 : Gaia DR3. Cross-match with known var. objects (Gavras+, 2023)
J/AJ/166/63 : Mind the Gap. I. Ha activity for M-Dwarfs (Jao+, 2023)
J/AJ/166/218 : New Gaia EDR3 binary cand. within 200pc of Sun (Medan+, 2023)
J/ApJS/266/40 : Stellar parameters from LAMOST MRS DR8 (Wang+, 2023)
J/ApJS/266/18 : Double-line spectroscopic binaries from LAMOST (Zheng+, 2023)
J/MNRAS/527/521 : SB2s in LAMOST-MRS (Kovalev+, 2024)
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 Designation for the stellar object
(JHHMMSS.ss+DDMMSS.s)
21- 30 I10 --- ObsID [101050/1018115126] Unique identifier for LAMOST
spectrum
32- 41 F10.6 deg RAdeg Right Ascension (J2000)
43- 51 F9.6 deg DEdeg [-9.4/90] Declination (J2000)
53- 58 F6.2 --- SNRr [5/299] Spectral signal to noise ratio in r-band
60- 65 F6.2 --- SNRi [5/299] Spectral signal to noise ratio in i-band
67- 69 A3 --- Subcl Spectral subclass from LAMOST pipeline
71- 75 I5 --- SpT [-2/8]?=-9999 Spectral subtype from SpT-TiO5
relation
77- 85 F9.6 mag Gmag [9.38/20.6]? Gaia DR3 G-band mean apparent
magnitude
87- 95 F9.6 mag BPmag [9.9/21.3]? Gaia DR3 BP mean apparent magnitude
97- 105 F9.6 mag RPmag [8.7/19]? Gaia DR3 RP mean apparent magnitude
107- 113 F7.4 pc Plx [1/98.3]? Gaia DR3 parallax
115- 120 F6.4 pc e_Plx [0.009/1.3]? Gaia DR3 error of Plx
122- 126 F5.3 --- RUWE [0.6/1.5]? Gaia Renormalized Unit Weight Error
128- 134 F7.2 km/s RV [-307/330] Radial velocity measured in this study
136- 140 F5.2 km/s e_RV [3.2/23] Typical uncertainty of RV
142- 145 I4 K Teff [2876/4276] Estimated effective temperature
147- 149 I3 K e_Teff [20/166] Typical uncertainty of Teff
151- 154 F4.2 [-] Logg [4.2/5.5] Estimated log of surface gravity
156- 159 F4.2 [-] e_Logg [0.03/0.4] Typical uncertainty of Logg
161- 165 F5.2 [-] [M/H] [-1.1/0.6] Estimated overall metallicity
167- 170 F4.2 [-] e_[M/H] [0.04/0.44] Typical uncertainty of [M/H]
172 I1 --- Ha? [0/1] Hα emission activity
(1=Hα emission detected)
174 I1 --- Var [0/2]? Potential variability or binarity (1)
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Note (1): Code as follows:
0 = default (479,782 occurrences)
1 = variable candidate (24,276 occurrences)
2 = binary candidate (3,455 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 08-Jan-2026