J/ApJS/274/36 Magnetic activity from LAMOST DR9, Gaia & TESS (Li+, 2024)
Physical parameters and magnetic activity of M-type stars based on the LAMOST
DR9, SDSS, and TESS surveys.
Li W., Zhang L.-Y., Su T., Han X.L., Misra P., Pi Q.
<Astrophys. J. Suppl. Ser., 274, 36 (2024)>
=2024ApJS..274...36L 2024ApJS..274...36L
ADC_Keywords: Stars, M-type; Spectra, optical; Photometry; Equivalent widths;
Redshifts; Abundances, [Fe/H]
Keywords: Stellar activity ; M stars
Abstract:
We analyze a catalog comprising 781,232 spectra from 641,095 M dwarf
stars from the Large Sky Area Multi-Object Fiber Spectroscopic
Telescope (LAMOST) low-resolution spectroscopic data release 9. Based
on the equivalent width of the Hα line, we ascertain the
activity properties of the stars, identifying a total of
107,134 active stars, with 31175 exhibiting Hα variations.
Furthermore, we establish a positive correlation between starspot
activity from Transiting Exoplanet Survey Satellite light curves, and
chromospheric activity observed through LAMOST spectra on M dwarf
stars. Utilizing LAMOST and Gaia data, we map the two-dimensional
distribution of active fractions across all M dwarfs in the Milky Way
based on Hα and Hβ lines, confirming a decrease in the
active fraction as the distance above the Galactic disk increases.
Additionally, we investigate the relationship between chromospheric
activity and absolute height above the Galactic disk in various M
subtypes. Our findings reveal distinct trends: for M0 to M5 dwarf
stars, the active fraction of Hα and Hβ lines rapidly
decreases within the 0-300pc range. In the 300-500pc range, M0 to M4
dwarf stars exhibit a gradual increase, followed by a decrease in the
500-1000 pc range. Conversely, M5 dwarf stars show no significant
gradual increase in the 300-500pc range and decrease in the 500-1000pc
range. More data will be needed to confirm the phenomenon.
Description:
Within this data set, we conducted a detailed statistical analysis on
the magnetic activity properties of 684,959 M dwarf stars using the
low-resolution spectral data of 832,755 LAMOST DR9 observations. The
low-resolution (R=1800) spectral wavelength spans the blue
(3700∼5900Å) and red (5700∼9000Å) regions. See Section 2.1.
Leveraging the rich data set of M dwarf stars from the SDSS DR7
survey, we conducted an in-depth examination of the magnetic activity
properties exhibited by M dwarf stars. See Section 2.2.
Leveraging the stellar light curves captured by the TESS telescope, we
executed a meticulous crossmatching process between the catalog of
M dwarf stars from LAMOST DR9 and objects in the TESS survey.
See Section 2.3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 135 781232 Stellar parameters of M dwarf stars from
LAMOST DR9 spectra
table2.dat 183 781232 Calculation parameters for M dwarf stars
table3.dat 95 440287 Hα variation of M dwarf stars from
LAMOST Low-resolution spectral DR9
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
J/ApJS/85/315 : F, G and K dwarf stars of the Pleiades (Soderblom+ 1993)
J/A+A/327/1039 : Structure and evolution of low-mass stars (Chabrier+ 1997)
J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)
J/AJ/128/426 : Subdwarfs in the SDSS (West+, 2004)
J/AJ/134/2398 : Stellar SEDs in SDSS and 2MASS filters (Covey+, 2007)
J/AJ/135/785 : SDSS-DR5 low-mass star spectroscopic sample (West+, 2008)
J/other/A+ARV/17.251 : Stars observed with Doppler imaging (Strassmeier, 2009)
J/AJ/140/1402 : M dwarf flares from SDSS spectra (Hilton+, 2010)
J/AJ/141/166 : HATNet variability survey of K and M dwarfs (Hartman+, 2011)
J/AJ/141/97 : SDSS DR7 M dwarfs (West+, 2011)
J/ApJ/795/161 : Activity & rotation in Praesepe & the Hyades (Douglas+, 2014)
J/ApJ/783/130 : Parallaxes of high mass star forming regions (Reid+, 2014)
J/MNRAS/476/908 : Chromospheric activity in 4 open clusters (Fang+, 2018)
J/ApJS/243/28 : M-type star magnetic activities (Lu+, 2019)
J/MNRAS/489/176 : Dynamical heating across the MW disc (Mackereth+, 2019)
J/ApJS/244/27 : Radial velocity measurements in LAMOST-II (Wang+, 2019)
J/ApJ/890/46 : Superflares on solar-type stars from TESS 1st yr (Tu+, 2020)
J/ApJS/247/9 : FGK stars magnetic activity in LAMOST-Kepler (Zhang+, 2020)
J/ApJS/253/19 : Halpha and other EWs of LAMOST M-type stars (Zhang+, 2021)
J/ApJS/260/45 : Stellar param. of M-type stars from LAMOST DR8 (Ding+, 2022)
J/ApJS/261/26 : Exoplanet host stars from LAMOST, TESS, Kepler (Su+, 2022)
J/ApJS/268/4 : Stellar var. with TESS 2min cadence phot. (Fetherolf+, 2023)
J/A+A/672/A37 : Activity indicators in M dwarfs (Ibanez Bustos+, 2023)
J/ApJS/264/17 : Spectroscopic data of TESS objects with LAMOST (Zhang+, 2023)
J/ApJS/271/60 : Magnetic activity of G-type stars (Su+, 2024)
http://www.lamost.org/dr9 : LAMOST DR9 home page
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 DR9 position-based Name (G1)
21- 29 F9.5 deg RAdeg LAMOST DR9 Right Ascension (J2000) (G1)
31- 38 F8.5 deg DEdeg LAMOST DR9 Declination (J2000) (G1)
40- 45 F6.2 --- SNR [0/822]? LAMOST DR9 spectrum signal-to-noise
ratio (G1)
47- 58 E12.3 0.1nm EWHa [-1499/2682]? LAMOST DR9 Hα equivalent
width in angstroms (G1)
60- 70 E11.2 0.1nm e_EWHa [0/713467]? Uncertainty in EWHa (G1)
72- 75 A4 --- SpT Spectral type subclass (G1)
77- 87 A11 --- z Redshift (G1)
89- 94 F6.3 [-] Fe/H [-2.5/0.5]? LAMOST DR9 metallicity (G1)
96- 99 F4.2 [-] e_Fe/H [0.08/0.9]? Uncertainty in FeH (G1)
101- 107 F7.2 K Teff [2300/4300]? LAMOST DR9 surface effective
temperature (G1)
109- 114 F6.2 K e_Teff [45/424]? Uncertainty in Teff (G1)
116- 121 F6.3 [cm/s2] logg [-0.5/6]? LAMOST DR9 log of surface
gravity (G1)
123- 126 F4.2 [cm/s2] e_logg [0.07/1]? Uncertainty in logg (G1)
128- 135 E8.3 --- CV [3.3e-06/2]? Coefficient of variation,
this work
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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 position-based Name
21- 27 F7.2 K Teff [2300/4300]? LAMOST DR9 surface effective
temperature (G1)
29- 34 F6.2 K e_Teff [45/424]? Uncertainty in Teff (G1)
36- 47 E12.3 0.1nm EWHa [-1499/2682]? LAMOST DR9 Hα equivalent
width in angstroms (G1)
49- 59 E11.2 0.1nm e_EWHa [0/713467]? Uncertainty in EWHa (G1)
61- 68 F8.3 mas/yr pmRA [-661/814]? Gaia DR3 (Epoch=2016.0) proper
motion in RA
70- 74 F5.3 mas/yr e_pmRA [0.005/2.5]? Uncertainty in pmRA
76- 84 F9.3 mas/yr pmDE [-1107/368]? Gaia DR3 (Epoch=2016.0) proper
motion in Dec
86- 90 F5.3 mas/yr e_pmDE [0.007/3]? Uncertainty in pmDE
92- 94 A3 --- Mark Activity indicator, Yes=Star is active
96- 102 F7.4 kpc Rad [2/22]? Star galactic radius, projected onto
the midplane
104- 111 F8.4 kpc Z [-17.4/32.1]? Stellar galactic scale height
113- 118 F6.2 d Per [0.01/437]? Period, based on VSX and TESS
120- 124 F5.3 Msun Mstar [0.1/2.3]? Mass from TESS Input Catalog v8.0
126- 136 E11.2 --- Ro [5.9e-05/13.3]? Rossby number
138- 149 E12.3 --- RHa [-0.2/0.002]? Chromospheric Hα activity
index, Equation 1
151- 161 E11.2 --- e_RHa [0/0.01]? Uncertainty in RHa
163- 174 F12.4 0.1nm EWHb [-11739/1443099]? Hβ equivalent width
in angstroms
176- 183 F8.3 0.1nm e_EWHb [0.005/8383]? Uncertainty in EWHb
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- LAMOST LAMOST position-based name
21- 29 F9.5 deg RAdeg Right Ascension
31- 38 F8.5 deg DEdeg [-9.2/78] Declination
40- 44 I5 d MJD [55858/59377] Modified Julian date
46- 49 I4 d dMJD [0/3422] Difference, maximum and minimum Julian
dates
51- 59 F9.3 0.1nm EWHa [-266/2682]? Equivalent width, Hα
61- 70 F10.3 0.1nm e_EWHa [0/209401]? Uncertainty in EWHa
72- 80 F9.3 0.1nm dHa [0/10046]? Difference, maximum and minimum EWHa
82- 91 F10.3 --- RHa [-34057/71930]? Ratio, max/min Hα
93- 95 A3 --- Mark Assessment of stellar activity based on the
Hα spectral line
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Global notes:
Note (G1): These stellar parameters are sourced from the LAMOST official
website for DR9, Version 1: http://www.lamost.org/dr9/v1.0/catalogue
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 12-Feb-2025