J/AJ/170/177 APOGEE: M dwarfs metallicity & planet parameters (Wanderley+, 2025)
Metallicities of M dwarf planet host stars from Kepler, K2, and TESS observed by
APOGEE: Trends with exoplanetary radii and orbital periods.
Wanderley F., Cunha K., Souto D., Smith V.V., Daflon S.
<Astron. J., 170, 177 (2025)>
=2025AJ....170..177W 2025AJ....170..177W
ADC_Keywords: Exoplanets; Stars, dwarfs; Stars, M-type; Stars, diameters;
Spectra, infrared; Photometry; Optical; Abundances
Keywords: Exoplanet evolution ; M dwarf stars ; Metallicity ;
Near infrared astronomy ; Planet hosting stars
Abstract:
One important property in studying the exoplanet population is the
host star metallicity ([M/H]). In this study, we derived stellar
metallicities and oxygen abundances for 48 M dwarf stars using the
near-infrared high-resolution spectra from the SDSS APOGEE survey and
synthetic spectra computed in LTE. We also investigated the
exoplanetary radii distribution for a larger sample of 246 exoplanets
orbiting 188 M dwarf stars. The [M/H] versus [O/M] distribution
obtained indicates that our sample is composed mainly of thin disk
stars, which follow the behavior of the low-alpha sequence in the
Milky Way thin disk. Small planets with radii smaller than 3R⊕
were found around stars with a range of metallicities (-0.6<[M/H]<+0.3),
while larger planets of the sample orbit only stars with [M/H]≥0.0.
These results indicate that while small planets can form in different
environments, larger planets preferentially form in metal-rich
protoplanetary disks. Exoplanets with Porb<4.3days orbit on average
more metal-rich stars than planets with longer periods. This threshold
is smaller than that found for FGK stars (8-10days) and might be
related to M dwarfs having a smaller dust sublimation radius. The
distribution of exoplanets with Rp>4R⊕ shows a concentration
at orbital periods between 2 and 5days, which may result from inward
orbital migration. There is also a different behavior between
single-detected exoplanets and planets from multiplanetary systems,
with the latter being found on average around more metal-poor stars,
and with planetary radii roughly up to 3R⊕.
Description:
The sample analyzed in this study comprises 246 exoplanets orbiting
188 M dwarf stars. This selection contains 218 exoplanets, which were
discussed in Wanderley+2025 (J/ApJ/993/233). In this study, we extend
the sample to include a population of larger exoplanets. In addition,
a subset of the M dwarfs in our sample was observed by the Apache
Point Observatory Galactic Evolution Experiment (APOGEE) survey (III/284),
allowing the determination of their stellar parameters (presented in
Wanderley+2025, J/ApJ/993/233), along with oxygen abundances and
metallicities (presented and discussed in this paper).
We note that in this study we have combined results from three
different missions (Kepler, K2, and the Transiting Exoplanet Survey
Statellite, TESS) and we investigated whether the overall conclusions
would change if we had considered results from each mission
independently. These are space telescopes, with coverages of 420-880nm
(Kepler/K2, same telescope, two missions) and 600-1000nm (TESS, IV/39).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 125 249 Stellar and planetary data
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See also:
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
IV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)
I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)
II/306 : The SDSS Photometric Catalog, Release 8 (Adelman-McCarthy+, 2011)
III/284 : APOGEE-2 data from DR16 (Johnsson+, 2020)
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/MNRAS/349/757 : Masses, ages & metallicities of F-G dwarfs (Lambert+, 2004)
J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)
J/MNRAS/367/1329 : Elemental abundances for 176 stars (Reddy+, 2006)
J/A+A/465/271 : Oxygen abundances in nearby stars (Ramirez+, 2007)
J/A+A/489/923 : Abundances of stars in lower main sequence (Mishenina+, 2008)
J/A+A/487/373 : Spectroscopic parameters of 451 HARPS-GTO stars (Sousa+, 2008)
J/ApJ/720/1290 : Abundances of stars hosting planets (Ghezzi+, 2010)
J/A+A/545/A32 : Chemical abundances of 1111 FGK stars (Adibekyan+, 2012)
J/other/Nat/486.375 : Stellar parameters of KOI stars (Buchhave+, 2012)
J/A+A/542/A33 : 3 M dwarfs near-infrared spectra (Onehag+, 2012)
J/ApJ/756/46 : Lithium abundances in HIP stars (Ramirez+, 2012)
J/AJ/143/93 : Rotational velocities in early-M stars (Reiners+, 2012)
J/ApJ/748/93 : K-band spectra for 133 nearby M dwarfs (Rojas-Ayala+, 2012)
J/AJ/145/52 : Abundances of late K & M dwarfs in binary systems (Mann+, 2013)
J/ApJ/770/43 : Spectroscopic [Fe/H] of Kepler stars (Mann+, 2013)
J/A+A/551/A36 : Metallicity of M dwarfs. III. (Neves+, 2013)
J/A+A/562/A71 : Chem. abundances of solar neighbourhood dwarfs (Bensby+, 2014)
J/ApJ/791/54 : Nearby M Dwarfs parameters (Gaidos+, 2014)
J/ApJS/213/5 : Cool KOIs. VI. H- and K- band spectra (Muirhead+, 2014)
J/AJ/147/20 : Spectroscopy of 447 nearby M dwarfs (Newton+, 2014)
J/A+A/577/A132 : Stellar parameters of early M dwarfs (Maldonado+, 2015)
J/ApJS/220/16 : SpeX NIR survey of 886 nearby M dwarfs (Terrien+, 2015)
J/AJ/151/144 : ASPCAP weights for the 15 APOGEE chem. elements (Garcia+, 2016)
J/AJ/152/187 : Planet occurrence & stellar metal. for KOIs (Mulders+, 2016)
J/AJ/154/109 : California-Kepler Surv (CKS). III. Planet radii (Fulton+, 2017)
J/A+A/614/A76 : CARMENES input catalogue of M dwarfs. III. (Jeffers+, 2018)
J/AJ/155/225 : M dwarf stars rotat. broadening measurements (Kesseli+, 2018)
J/AJ/155/89 : California-Kepler Survey (CKS). IV. Planets (Petigura+, 2018)
J/A+A/620/A180 : Stellar properties of M dwarfs (Rajpurohit+, 2018)
J/AJ/156/254 : Cal-Kepler Surv.VI. Kepler multis & singles (Weiss+, 2018)
J/AJ/155/68 : Elemental abundances of KOIs in APOGEE. I. (Wilson+, 2018)
J/AJ/158/87 : 86 cool dwarfs observed during K2 Camp. 1-17 (Dressing+, 2019)
J/MNRAS/483/1125 : Rad. inflation in Praesepe active M-dwarfs (Jackson+, 2019)
J/ApJ/875/29 : Spectroscopic analysis of the CKS sample. I. (Martinez+, 2019)
J/ApJ/892/31 : Teff & metallicities of M dwarfs in APOGEE DR14 (Birky+, 2020)
J/ApJ/920/19 : Spectr. analysis of CKS. II. Metallicities (Ghezzi+, 2021)
J/A+A/656/A162 : CARMENES stellar atmospheric parameters (Marfil+, 2021)
J/A+A/649/A147 : Spectroscopic parameters for 313 M dwarfs (Sarmento+, 2021)
J/ApJ/917/11 : Metal. of Coma Berenices bona fide members (Souto+, 2021)
J/other/Sci/377.1211 : RV and LC of 8 M dwarf stars with planets (Luque+, 2022)
J/A+A/658/A194 : Stellar parameters of 18 M dwarfs (Passegger+, 2022)
J/A+A/673/A105 : Deep Transfer Learning of Teff and [M/H] (Bello-Garcia+, 2023)
J/ApJ/993/233 : Stellar & planetary param. of M-dwarf systems (Wanderley+ 2025)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 14 A14 --- Host Hostname identifier
16- 21 F6.2 pc Dist [6.48/380.73] Stellar distance from
Bailer-Jones+2021 (I/352) (d)
23- 26 F4.2 pc e_Dist [0/4.42] Uncertainty in Dist
28- 33 F6.1 K Teff [3260/3988]? Effective temperature (1)
35- 38 F4.2 [-] logg [4.62/5.13]? Log of surface gravity (1)
40- 44 F5.2 [-] [M/H] [-0.56/0.26]? Stellar metallicity (1)
46- 49 F4.2 km/s vsini [1/9.27]? Stellar projected rotational velocity
51- 54 F4.2 [-] A(O) [8.25/8.87]? Oxygen abundance
56- 59 F4.2 mag KsMag [4.98/7.51] Absolute Ks magnitude
(2MASS, II/246)
61- 64 F4.2 Rsun R* [0.24/0.59] Stellar radius
66- 69 F4.2 Rsun e_R* [0.01/0.03] Uncertainty in R*
71- 86 A16 --- Planet Exoplanet identifier
88- 92 F5.2 % Depth [0.01/11.02]? Transit depth (dF)
94- 97 F4.2 % E_Depth [0/0.16]? Superior uncertainty in Depth
99- 102 F4.2 % e_Depth [0/0.16]? Inferior uncertainty in Depth
104- 108 F5.2 Rgeo Rp [0.57/12.61]? Planetary radius
110- 113 F4.2 Rgeo E_Rp [0.03/0.6]? Superior uncertainty in Rp
115- 118 F4.2 Rgeo e_Rp [0.03/0.6]? Inferior uncertainty in Rp
120- 125 F6.2 d Porb [0.24/207.25] Planetary orbital period
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Note (1): The Teff, logg, and metallicity uncertainties are, respectively,
±100K, ±0.20dex, and ±0.14dex.
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History:
From electronic version of the journal
License: CC-BY-4.0
(End) Prepared by [AAS], Robin Leichtnam [CDS] 06-Jul-2026