J/ApJS/280/19 LK-MRS Phase II. 5 year obs. from LAMOST DR11 (Qin+, 2025)
Phase II of the LAMOST-Kepler/K2 Survey.
II. Time domain of Medium-Resolution Spectroscopic observations from 2018
to 2023.
Qin M., Fu J.-N., Zong W., De Cat P., Frasca A., Cang T., Wang J., Shi J.,
Luo A., Zhang H., Yan H., Molenda-Zakowicz J., Gray R.O., Wang J.
<Astrophys. J. Suppl. Ser., 280, 19 (2025)>
=2025ApJS..280...19Q 2025ApJS..280...19Q
ADC_Keywords: Spectra, optical; Abundances; Radial velocities; Surveys;
Rotational velocities; Stars, metal-deficient; Stars, variable
Keywords: Spectroscopy ; Catalogs ; Surveys ; Astronomy databases ;
Fundamental parameters of stars
Abstract:
The LAMOST-Kepler/K2 Medium-Resolution Spectroscopic Survey (LK-MRS)
conducted time-domain (TD) medium-resolution spectroscopic
observations of 20 LAMOST plates in the Kepler and K2 fields from 2018
to 2023, a phase designated as LK-MRS-I. A catalog of stellar
parameters for a total of 36,588 stars, derived from the spectra
collected during these 5yr, including the effective temperature, the
surface gravity, the metallicity, the α-element abundance, the
radial velocity (RV), and vsini of the target stars, is released,
together with the weighted averages and uncertainties. At a
signal-to-noise ratio = 10, the measurement uncertainties are 120K,
0.18dex, 0.13dex, 0.08dex, 1.9km/s, and 4.0km/s for the above
parameters, respectively. Comparisons with the parameters provided by
the APOGEE and GALAH surveys validate the effective temperature and
surface gravity measurements, showing minor discrepancies in
metallicity and α-element abundance values. We identified some
peculiar star candidates, including 764 metal-poor stars, 174 very
metal-poor stars, and 30 high-velocity stars. Moreover, we found
2333 stars whose RV seems to be variable. Using Kepler/K2 or TESS
photometric data, we confirmed 371 periodic variable stars among the
RV variable candidates and classified their variability types.
LK-MRS-I provides spectroscopic data that is useful for studies of the
Kepler and K2 fields. The LK-MRS project will continue collecting TD
medium-resolution spectra for target stars during the third phase of
LAMOST surveys, providing data to support further scientific research.
Description:
Since 2018 October, LAMOST has launched its second-phase surveys,
which include both a low-resolution spectroscopic survey (LRS) and
Medium-Resolution Spectroscopic Survey (MRS).
To integrate Kepler time-series photometry with time-domain (TD) MRS
data and enable extensive large-sample studies of Kepler/K2 targets,
the LAMOST-Kepler/K2 Medium-Resolution Spectroscopic Survey (LK-MRS)
has strategically selected four observational plates within the Kepler
field and 16 plates in the K2 fields, for a total of 20 plates (see
Paper I, Zong+ 2020, J/ApJS/251/15).
LK-MRS-I conducted TD spectroscopic observations from 2018 September
to 2023 June, covering both the Kepler and K2 fields. The distribution
of all observed plates in the celestial coordinate system is shown in
Figure 1.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 257 36556 Stellar atmospheric parameters provided by LK-MRS-I
table4.dat 97 938 Metal-poor star candidates identified in LK-MRS-I
table5.dat 113 30 High velocity star candidates identified in LK-MRS-I
table6.dat 124 17326 RVs of 2336 variable star candidates of the LK-MRS-I
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See also:
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-)
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
IV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
III/286 : APOGEE-2 DR17 final allStar catalog (Abdurro'uf+, 2022)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
V/162 : LAMOST DR11 catalogs (Luo+, 2026)
J/ApJS/215/19 : APOKASC catalog of Kepler red giants (Pinsonneault+, 2014)
J/ApJS/220/19 : LAMOST obs. in the Kepler field. I. (De Cat+, 2015)
J/ApJS/229/30 : Revised properties of Q1-17 Kepler targets (Mathur+, 2017)
J/ApJS/233/23 : APOKASC cat. of KIC dwarfs and subgiants (Serenelli+, 2017)
J/ApJS/239/32 : APOKASC-2 cat. of Kepler evolved stars (Pinsonneault+, 2018)
J/ApJS/238/30 : LAMOST obs. in Kepler field. II. LRS sp. (Zong+, 2018)
J/MNRAS/485/2380 : Gaia-derived luminosities of Kepler stars (Murphy+, 2019)
J/ApJS/244/27 : Radial velocity measurements in LAMOST-II (Wang+, 2019)
J/A+A/643/A83 : K2-Gaia-ESO stellar param. and abundances (Worley+, 2020)
J/MNRAS/493/1388 : Asteroseismology of luminous giants with Kepler (Yu+, 2020)
J/ApJS/251/15 : LAMOST-Kepler/K2 survey (LK-MRS) 1rst yr obs. (Zong+, 2020)
J/MNRAS/506/150 : The GALAH+ Survey DR3 (Buder+, 2021)
J/ApJS/252/3 : High-velocity stars in the Galactic halo (Li+, 2021)
J/ApJS/256/14 : RVs from LAMOST MRS DR7 stellar spectra (Zhang+, 2021)
J/A+A/664/A78 : Kepler targets class based on LAMOST spectra (Frasca+, 2022)
J/ApJS/258/26 : Spectroscopic binaries from LAMOST MRS. I. (Zhang+, 2022)
J/ApJS/264/12 : Chromospheric activities from LAMOST and K2 (Han+, 2023)
J/ApJ/952/131 : Magnetic activity evol. of solar-like stars (Mathur+, 2023)
J/ApJS/266/40 : Stellar parameters from LAMOST MRS DR8 (Wang+, 2023)
J/A+A/689/A224 : Precise Fourier param. of Cepheids RV curves (Hocde+, 2024)
J/AJ/167/280 : Photometry and spectroscopy of V505 Lac (Jeong+, 2024)
J/AJ/167/76 : Catalog of 519 high velocity stars (HiVels) (Liao+, 2024)
J/AJ/168/253 : RVs of TIC 56913729 & TIC 97729372 from LAMOST (Pan+, 2024)
J/AJ/167/253 : Utlra cool dwarfs comoving companions (Rothermich+, 2024)
J/A+A/690/A201 : Detached EBs lifetime of starspots (Wang+, 2024)
J/ApJS/271/4 : Rotational velocities for LAMOST DR9 stars (Zuo+, 2024)
J/A+A/698/A7 : Pleiades LAMOST mid-resolution observations (Frasca+, 2025)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- Seq [0/36555] Sequential identifier
7- 8 I2 --- Freq [1/29] Number of available spectral parameters
10- 24 A15 --- uID Unique id of the LAMOST DR11 observation
26- 34 I9 --- EPIC [201847044/251813738]? EPIC identifier
36- 43 I8 --- KIC [5091962/11558398]? Kepler input catalog id
45- 54 F10.6 deg RAdeg [10/298] Right Ascension (J2000)
56- 65 F10.7 deg DEdeg [0.7/49.6] Declination (J2000)
67- 77 F11.6 K Teff [3114/8497]? Stellar surface effective
temperature
79- 92 F14.9 K e_Teff [0.006/2842]? Uncertainty in Teff
94- 105 F12.9 [cm/s2] logg [-0.035/4.93]? Log of stellar surface
gravity
107- 117 E11.5 [cm/s2] e_logg [0/3.2]? Uncertainty in logg
119- 130 E12.5 [-] FeH [-2.5/0.9]? Stellar metallicity
132- 142 E11.5 [-] e_FeH [0/1.6]? Uncertainty in FeH
144- 155 E12.5 [-] [a/M] [-0.6/0.6]? Stellar α abundance ratio
157- 167 E11.5 [-] e_[a/M] [1.8e-06/0.5]? Uncertainty in [a/M]
169- 182 F14.9 km.s-1 RVel [-259/346]? Stellar radial velocity
184- 194 E11.5 km.s-1 e_RVel [0/239]? Uncertainty in radial velocity
196- 207 F12.8 km.s-1 vsini [27/349]? Projected rotational velocity
209- 221 F13.9 km.s-1 e_vsini [0.0027/172]? Uncertainty in vsini
223- 241 I19 --- Gaia Gaia DR3 Source identifier
243- 257 A15 --- Class Classification flags or additional comments (1)
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Note (1): Classification flags as follows:
MP = metal-poor with -2.0≲[Fe/H]<-1.0
VMP = very metal-poor with [Fe/H]≲-2.0
unbound = unbound high-velocity candidate
bound = bound high-velocity candidate
RVV = RV variable star candidates
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [0/937] Sequential identifier
5- 6 I2 --- Freq [1/16] Number of available spectral parameters
8- 22 A15 --- uid Unique id (uid) of the LAMOST DR11 observation
24- 42 I19 --- Gaia Gaia DR3 Source id
44- 52 I9 --- kepID ? EPIC or KIC identifier
(EPIC numbers if >201000000 else KIC numbers)
54- 63 F10.6 deg RAdeg [10.36/297.2] Right Ascension (J2000)
65- 74 F10.7 deg DEdeg [0.8/49.1] Declination (J2000)
76- 87 F12.9 [-] FeH [-2.5/-1] Stellar metallicity
89- 91 A3 --- Class Metallicity classification (1)
93- 97 A5 --- New? Discovery status (2)
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Note (1): Metallicity classification flag as follows:
MP = metal-poor with -2.0≲[Fe/H]<-1.0 (764 occurrences)
VMP = very metal-poor with [Fe/H]≲-2.0 (174 occurrences)
Note (2): Discovery status as follows:
Known = present in SIMBAD (129 occurrences)
New = newly recognized in this work (809 occurrences)
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Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [0/29] Sequential identifier
4- 5 I2 --- Freq [1/13] Number of available spectral parameters
7- 21 A15 --- uid Unique id (uid) of the LAMOST DR11 observation
23- 41 I19 --- Gaia Gaia DR3 Source id
43- 51 I9 --- kepID [5439372/248671171]? EPIC or KIC identifier
(EPIC numbers if >201000000 else KIC numbers)
53- 62 F10.6 deg RAdeg [13/297] Right Ascension (J2000)
64- 72 F9.6 deg DEdeg [3.5/49.1] Declination (J2000)
74- 87 F14.9 km/s HRV [-259/296] Heliocentric radial velocity
89- 99 F11.7 km/s Vgc [351.4/577.3] Galactic standard-of-rest velocity
101-107 A7 --- Flag Kinematic comment (1)
109-113 A5 --- New? Discovery status (2)
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Note (1): Kinematic comment as follows:
unbound = unbound high-velocity candidate;
bound = bound high-velocity candidate.
Note (2): Discovery status as follows:
Known = present in SIMBAD (4 occurrences)
New = newly recognized in this work (26 occurrences)
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Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- uid Unique id (uid) of the LAMOST DR11 observation
17- 35 I19 --- Gaia Gaia DR3 Source id
37- 47 F11.7 deg RAdeg [10/298] Right Ascension (J2000)
49- 58 F10.7 deg DEdeg [0.7/47] Declination (J2000)
60- 64 I5 d MJD [58266/60099] Modified Julian date of
observation (JD-2400000.5)
66- 71 F6.2 --- SNR [10/331.2] Signal to noise ratio of observation
73- 79 F7.2 km/s RVel [-314/416] Stellar radial velocity
81- 85 F5.2 km/s e_RVel [0.28/80] Uncertainty in RVel
87- 95 I9 --- kepID [5273178/251405485]? EPIC or KIC identifier
(EPIC numbers if >201000000 else KIC numbers)
97- 106 I10 --- TIC [6890336/1881514235]? TESS input catalog id
108- 118 A11 --- Var Variability (1)
120- 124 A5 --- New? Discovery status (2)
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Note (1): Variability Label as follows:
binary = eclipsing binaries (687 occurrences)
delta = delta∼Scuti variables (77 occurrences)
gamma = gamma∼Doradus variables (486 occurrences)
gamma+delta = hybrid gamma∼Doradus and delta∼Scuti variables (127 occurrences)
red giant = red giants with solar-like oscillations (137 occurrences)
rot = rotating variable stars (1148 occurrences)
RR = RR Lyrae variables (30 occurrences)
RS = RS Canum Venaticorum variables (130 occurrences)
unknown = variability types remain uncertain (50 occurrences)
Note (2): Discovery Status as follows:
Known = present in SIMBAD (1475 occurrences)
New = newly recognized in this work (1397 occurrences)
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History:
From electronic version of the journal
References:
Zong et al. Paper I. 2020ApJS..251...15Z 2020ApJS..251...15Z Cat. J/ApJS/251/15
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 25-Mar-2026