J/ApJS/280/26 Eclipsing binaries from LAMOST DR10, TESS and VSX (Shi+, 2025)
Physical parameters and chromospheric activity of eclipsing binaries observed
by the LAMOST DR10 survey.
Shi A., Zhang L.-Y., Su T., Wang Y., An Qi, Han X.L., Misra P., Jiang L.,
Guo R., Pi Q.
<Astrophys. J. Suppl. Ser., 280, 26 (2025)>
=2025ApJS..280...26S 2025ApJS..280...26S
ADC_Keywords: Binaries, eclipsing; Spectral types; Photometry; Optical;
Spectra, optical; Abundances, [Fe/H]; Equivalent widths;
Stars, masses; Stars, flare; Stars, variable
Keywords: Stellar chromospheres ; Stellar activity
Abstract:
In this study, we present a comprehensive study of more than 50000
spectra of 32257 eclipsing binaries from the LAMOST DR10 survey,
including 5200 systems with spectroscopy. We quantified their
chromospheric activity through Hα spectral subtraction with
iSpec, among 20000 binaries showing significant excess emission. The
chromospheric activity increases toward shorter orbital periods and
lower metallicity. By combining tidally locked rotation periods with
convective turnover times, we have computed their Rossby numbers and
uncovered a geometry-driven shift in the saturation threshold: the
detached EA systems saturate at logRo~-1.3 (Ro∼0.05), whereas
equivalent width (EW) contact binaries, owing to their common
convective envelope (CCE), do not reach saturation until logRo~-1.6
(Ro∼0.025). The CCE enlarges the magnetic-flux reservoir via
L1-spanning field lines and strong shear effects, demanding faster
rotation to attain the chromospheric limit. For Ro≲0.02, we observe a
mild downturn consistent with supersaturation. The high- precision
Transiting Exoplanet Survey Satellite light curves for 4326 eclipsing
binaries reveal starspot amplitudes that correlate tightly with the
Hα activity, confirming enhanced magnetism in close binaries. We
have detected 1752 flare events (1179 from 208 EA, 429 from 44 EB,
144 from EW) on eclipsing binaries. We also determined their
parameters and the flare frequency distributions in the different
types of eclipsing binaries. In the end, we also give the plan of
eclipsing binaries in the LAMOST low and medium-resolution spectra
future survey.
Description:
LAMOST, also known as the Guo Shoujing Telescope, is a major optical
telescope project located at the Xinglong Observatory of the National
Astronomical Observatories in Hebei Province, China. Since its
operation began in 2013, LAMOST has released annual data updates, with
data release 10 (DR10), used in this study, made publicly available on
2022 June 30.
By crossmatching the International Variable Star Index (VSX;
Watson+ 2006, See B/vsx) with the low-resolution spectroscopic data
from LAMOST DR10, we obtained 9250, 2386, and 20,621 EA-, EB-, and
EW-type systems, respectively, that have been observed by LAMOST.
We further cross-matched our samples with TESS data.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 233 51033 Physical parameter and chromospheric activity of
eclipsing binaries
table2.dat 86 53421 Hα and RV variability of eclipsing binaries
based on LAMOST spectra
table3.dat 88 1902 Flare parameters for 286 eclipsing binaries in TESS
survey
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See also:
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-)
B/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
V/162 : LAMOST DR11 catalogs (Luo+, 2026)
J/A+A/397/147 : Activity-rotation relationship in stars (Pizzolato+ 2003)
J/AJ/128/426 : Subdwarfs in the SDSS (West+, 2004)
J/ApJ/743/48 : Stars with rot. periods & X-ray luminosities (Wright+, 2011)
J/ApJ/829/23 : Stellar flares from Q0-Q17 Kepler LCs (Davenport, 2016)
J/ApJS/224/37 : White-light flares on close binaries from Kepler (Gao+, 2016)
J/ApJ/834/207 : Periodicity & mag. of Kepler LCs variation (Mehrabi+, 2017)
J/ApJ/834/85 : Hα emission in nearby M dwarfs (Newton+, 2017)
J/ApJ/849/36 : Flaring activity of M dwarfs in Kepler field (Yang+, 2017)
J/MNRAS/476/908 : Chromospheric activity in 4 open clusters (Fang+, 2018)
J/AJ/156/220 : V, R and I LCs of 4 new low-mass M-type EBs (Long+, 2018)
J/ApJS/235/5 : EA-type eclipsing binaries observed by LAMOST (Qian+, 2018)
J/A+A/622/A133 : M45, M44 and M67 flare stars (Ilin+, 2019)
J/ApJ/871/187 : Spot parameters on KIC solar-type stars (Namekata+, 2019)
J/other/RAA/19.64 : LAMOST spectroscopic binaries & var. stars (Qian+, 2019)
J/other/RAA/20.163 : Contact binaries in LAMOST DR7 (Qian+, 2020)
J/ApJS/247/9 : FGK stars magnetic activity in LAMOST-Kepler (Zhang+, 2020)
J/ApJ/926/204 : TESS obs. campaign of low-mass flare stars (Howard+, 2022)
J/A+A/669/A15 : TESS flare events and physical parameters (Yang+, 2023)
J/ApJS/264/17 : Spectroscopic data of TESS objects with LAMOST (Zhang+, 2023)
J/ApJS/271/60 : Magnetic activity of G stars from LAMOST+TESS (Su+, 2024)
J/A+A/686/A164 : Magnetic activity of radio stars (Wang+, 2024)
J/ApJS/277/51 : ASAS-SN contact binaries from neural network (Li+, 2025)
J/ApJS/276/44 : TIC star magnetic activity with LAMOST DR10 MRS (Su+, 2025)
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 Source name (JHHMMSS.ss+DDMMSS.s)
21- 22 A2 --- Type Binary subtype (1)
24- 33 A10 --- SpType Stellar spectral type
35- 44 F10.4 d MJD [55858.5/59732.51] Modified Heliocentric
Julian day
46- 53 F8.2 --- snru [0/676]? S/N of u filter
55- 62 F8.2 --- snrg [0/999]? S/N of g filter
64- 71 F8.2 --- snrr [0/999]? S/N of r filter
73- 80 F8.2 --- snri [0/999]? S/N of i filter
82- 89 F8.2 --- snrz [0/999]? S/N of z filter
91- 97 F7.2 mag imag [8.45/22.34]? Pan-STARRS i band magnitude
99- 106 F8.4 deg RAdeg Right ascension at the time of LAMOST
observation (J2000)
108- 114 F7.4 deg DEdeg [-9.6/88] Declination at the time of LAMOST
observation (J2000)
116- 125 F10.4 d Period [0.06/25245]? Orbital period
127- 131 F5.3 Msun Mass [0.47/2.6]? Stellar mass estimate from TESS
133- 139 F7.1 K Teff [2859/53630]? Effective temperature obtained
by LASP
141- 147 F7.1 K e_Teff [3/4387]? The 1σ uncertainty in Teff
149- 156 F8.2 [cm/s2] logg [0.14/9.63]? Surface gravity obtained by the
LASP
158- 165 F8.2 [cm/s2] e_logg [0/1.2]? The 1σ uncertainty in logg
167- 171 F5.2 [-] FeH [-2.5/0.95]? Metallicity obtained by the LASP
173- 180 F8.2 [-] e_FeH [0/0.9]? The 1σ uncertainty in FeH
182- 188 F7.2 km/s RVel [-324/369]? Heliocentric radial velocity
obtained by LASP
190- 197 F8.2 km/s e_RVel [0.5/77]? The 1σ uncertainty in RVel
199- 204 F6.2 0.1nm EWHa [-4.6/734]? Hα equivalent width
206- 210 F5.2 0.1nm e_EWHa [0/11.4]? The 1σ uncertainty in EWHa
212- 216 F5.2 --- RHa [0/0.2]? Chromospheric activity level
estimated using bolometric correction
218- 221 F4.2 --- Ro [0/5.1]? Rossby number
223- 226 F4.2 --- Reff [0/0.6]? Effective photometric modulation
amplitude
228- 231 F4.2 --- e_Reff [0/0.01]? The 1σ uncertainty in Reff
233 A1 --- Cl Activity classification flag
(Y=active system; N=inactive)
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Note (1): Type as follows:
EA = Algol-type, detached (15748 occurrences)
EB = semi-detached, Β Lyrae-type (6917 occurrences)
EW = contact, W UMa-type (28368 occurrences)
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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 Name (JHHMMSS.ss+DDMMSS.s)
21- 30 F10.4 d HJD [55858.49/59732.51] Heliocentric Julian Date
32- 38 F7.3 0.1nm EWHa [-4.6/734]? Hα net equivalent width;
EW'Hα in Angstroms
40- 45 F6.3 0.1nm e_EWHa [0.001/11.4]? Uncertainty in EWHa
47- 52 F6.4 0.1nm DelEWHa [0/4.9]? Difference between max and min values
of EWHa
54- 62 F9.4 --- RatEWHa [-319/481]? Ratio of EWHa max to min
64 A1 --- VHa Hα variability flag (Y=variability;)
or N=nonvariability)
66- 73 F8.4 km/s DelRV [0/253]? Difference between max and min values
of RV
75- 84 F10.4 --- RatRV [-1801/623]? Ratio of RV max to min
86 A1 --- VRV RV variability flag (Y=variability
or N=nonvariability)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Type Eclipsing binary type from B/vsx (1)
11- 19 I9 --- TIC [737327/950715112] TESS Input Catalog identifier
21- 29 F9.4 d tstart [1326.79/3338.94] Flare start date (2)
31- 36 F6.4 d trise [0.0014/0.08] Flare rise date
38- 46 F9.4 d tpeak [1326.8/3338.97] Peak date of flare (2)
48- 53 F6.4 d tdecay [0.0042/0.12] Flare rise decay
55- 63 F9.4 d tend [1326.8/3339.02] Flare end date (2)
65- 70 F6.4 d duration [0.0056/0.19] Flare duration
72- 77 F6.4 --- Amp [0.0012/2.79] Flare amplitude; normalized flux
79- 88 E10.4 10-7J Ebol ? Estimated bolometric flare energy; ergs
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Note (1): Including:
EA = Algol-type, detached;
EB = semi-detached, Β Lyrae-type;
EW = contact, W UMa-type.
Note (2): All times are given relative to BJD 2457000 to match TESS conventions.
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History:
From electronic version of the journal
License: CC-BY-4.0
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 03-Jun-2026