J/AJ/159/193 Stellar parameters of ∼30000 LAMOST DR1 M dwarfs (Galgano+, 2020)
Fundamental parameters of ∼30000 M dwarfs in LAMOST DR1 using data-driven
spectral modeling.
Galgano B., Stassun K., Rojas-Ayala B.
<Astron. J., 159, 193 (2020)>
=2020AJ....159..193G 2020AJ....159..193G
ADC_Keywords: Stars, dwarfs; Stars, M-type; Stars, diameters; Stars, masses;
Spectral types; Spectra, optical; Effective temperatures
Keywords: Stellar properties ; Low mass stars ; Astronomy data modeling
Abstract:
M-dwarfs are the most common type of star in the Galaxy, and because
of their small size are favored targets for searches of Earth-sized
transiting exoplanets. Current and upcoming all-sky spectroscopic
surveys, such as the Large Sky Area Multi Fiber Spectroscopic
Telescope (LAMOST), offer an opportunity to systematically determine
physical properties of many more M dwarfs than has been previously
possible. Here, we present new effective temperatures, radii, masses,
and luminosities for 29678 M dwarfs with spectral types M0-M6 in the
first data release (DR1) of LAMOST. We derived these parameters from
the supervised machine-learning code, The Cannon, trained with 1388
M-dwarfs in the Transiting Exoplanet Survey Satellite Cool Dwarf
Catalog that were also present in LAMOST with high signal-to-noise
ratio (>250) spectra. Our validation tests show that the output
parameter uncertainties are strongly correlated with the
signal-to-noise of the LAMOST spectra, and we achieve typical
uncertainties of 110K in Teff(∼3%), 0.065R☉(∼14%) in radius,
0.054M☉(∼12%) in mass, and 0.012L☉(∼20%) in luminosity.
The model presented here can be rapidly applied to future LAMOST data
releases, significantly extending the samples of well-characterized M
dwarfs across the sky using new and exclusively data-based modeling
methods.
Description:
The data are drawn from two main catalogs:
(1) the LAMOST first data release (DR1) M dwarf catalog (Guo+, 2015,
J/other/RAA/15.1182), the spectral data set that we wish to classify;
and
(2) the Transiting Exoplanet Survey Satellite (TESS) Cool Dwarf
Catalog (TCD; Muirhead+ 2018, J/AJ/155/180), whose parameters we
utilize for training and validation of The Cannon model (see
Ness+, 2015, J/ApJ/808/16).
The Large Sky Area Multi Fiber Spectroscopic Telescope (LAMOST) is a
low resolving power (R∼1800), optical/near-infrared (3690-9100Å),
ground-based survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 94 33095 Resulting stellar parameter values from applying
the Cannon M dwarf model to LAMOST spectra
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See also:
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
V/164 : LAMOST DR5 catalogs (Luo+, 2019)
VI/156 : M-dwarf Lum-Temp-Radius relationships (Morrell+, 2019)
J/AJ/130/1871 : Spectroscopic survey of M dwarfs (Bochanski+, 2005)
J/MNRAS/389/585 : Fundamental parameters of M dwarfs (Casagrande+, 2008)
J/ApJ/748/93 : K-band spectra of 133 nearby M dwarfs (Rojas-Ayala+,2012)
J/AJ/145/102 : Spectroscopy of M dwarfs in northern sky (Lepine+, 2013)
J/other/RAA/15.1182 : M Dwarf catalog of LAMOST DR1 (Guo+, 2015)
J/A+A/577/A132 : Stellar parameters of early M dwarfs (Maldonado+, 2015)
J/AJ/150/42 : Catalog of 2612 M dwarfs from LAMOST (Zhong+, 2015)
J/ApJ/804/64 : Empirical & model parameters of 183 M dwarfs (Mann+,2015)
J/ApJ/808/16 : The Cannon: approach to determine abundances (Ness+,2015)
J/ApJ/823/114 : The Cannon: approach to determine masses (Ness+, 2016)
J/ApJ/836/5 : Abundances of LAMOST giants from APOGEE DR12 (Ho+, 2017)
J/ApJ/851/26 : Teff, Fe/H & Ti abundance of M dwarfs (Veyette+, 2017)
J/AJ/155/180 : A catalog of cool dwarf targets for TESS (Muirhead+,2018)
J/AJ/156/217 : Properties M dwarfs in MEarth-South (Newton+, 2018)
J/ApJ/871/63 : How to constrain your M dwarf II (Mann+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- LAMOST LAMOST DR1 Designation (JHHMMSS.ss+DDMMSS.s)
21- 28 F8.3 K Teff [2900/4114] Cannon derived effective temperature
30- 37 F8.3 K e_Teff [89/3699] Formal (1σ) error in Teff (1)
39- 43 F5.3 Rsun Rstar [0.13/0.67] Cannon derived stellar radius
45- 49 F5.3 Rsun e_Rstar [0.04/1.9] Formal (1σ) error in Rstar (1)
51- 55 F5.3 Msun Mstar [0.1/0.71] Cannon derived stellar mass
57- 61 F5.3 Msun e_Mstar [0.05/2.3] Formal (1σ) error in Mstar (1)
63- 67 F5.3 Lsun Lstar [0.002/0.12] Cannon derived stellar luminosity
69- 73 F5.3 Lsun e_Lstar [0.01/0.31] Formal (1σ) error in Lstar (1)
75- 76 A2 --- SpT LAMOST spectral subtype
78- 85 F8.3 --- SNRl [50/1362] Summed signal-to-noise quality metric
(SNRλ) (2)
87- 94 F8.3 --- chi2 [369/4998] Reduced χ2 of the fit
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Note (1): The formal error (1σ) has been estimated from the best
fitted polynomial function of SNRλ (see Section 4.3, Figure 5
and Table 2).
Note (2): The quality metric SNRλ is calculated
from the sum of the measured SNRs in the individual LAMOST
quasi-photometric bands (ugriz).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 20-May-2020