The CARMENES search for exoplanets around M dwarfs - Photospheric parameters of target stars from high-resolution spectroscopy

Abstract

The new CARMENES instrument comprises two high-resolution and high-stability spectrographs that are used to search for habitable planets around M dwarfs in the visible and near-infrared regime via the Doppler technique. Characterising our target sample is important for constraining the physical properties of any planetary systems that are detected. The aim of this paper is to determine the fundamental stellar parameters of the CARMENES M-dwarf target sample from high-resolution spectra observed with CARMENES. We also include several M-dwarf spectra observed with other high-resolution spectrographs, that is CAFE, FEROS, and HRS, for completeness. We used a {chi}^2 method to derive the stellar parameters effective temperature T_eff, surface gravity log g, and metallicity [Fe/H] of the target stars by fitting the most recent version of the PHOENIX-ACES models to high-resolution spectroscopic data. These stellar atmosphere models incorporate a new equation of state to describe spectral features of low-temperature stellar atmospheres. Since T_eff, log g, and [Fe/H] show degeneracies, the surface gravity is determined independently using stellar evolutionary models. We derive the stellar parameters for a total of 300 stars. The fits achieve very good agreement between the PHOENIX models and observed spectra. We estimate that our method provides parameters with uncertainties of {sigma} T_eff = 51 K, {sigma} log g = 0.07, and {sigma} [Fe/H] = 0.16, and show that atmosphere models for low-mass stars have significantly improved in the last years. Our work also provides an independent test of the new PHOENIX-ACES models, and a comparison for other methods using low-resolution spectra. In particular, our effective temperatures agree well with literature values, while metallicities determined with our method exhibit a larger spread when compared to literature results.

References in corpus (32)

• The chemical composition of the Sun
• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• A new extensive library of PHOENIX stellar atmospheres and synthetic spectra
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• A Non-Gray Theory of Extrasolar Giant Planets and Brown Dwarfs
• Models of Stars, Brown Dwarfs and Exoplanets
• How to Constrain Your M Dwarf: measuring effective temperature, bolometric luminosity, mass, and radius
• Stellar Diameters and Temperatures II. Main Sequence K & M Stars
• Theory of Low-Mass Stars and Substellar Objects
• Spectrum radial velocity analyser (SERVAL). High-precision radial velocities and two alternative spectral indicators
• Metallicity and Temperature Indicators in M dwarf K band Spectra: Testing New & Updated Calibrations With Observations of 133 Solar Neighborhood M dwarfs
• The H$\alpha$ emission of nearby M dwarfs and its relation to stellar rotation
• Parallel Implementation of the PHOENIX Generalized Stellar Atmosphere Program
• The Effective Temperature Scale of M dwarfs
• The Solar Neighborhood XXXVII: The Mass-Luminosity Relation for Main Sequence M Dwarfs
• A catalogue of rotation and activity in early-M stars
• Prospecting in late-type dwarfs: a calibration of infrared and visible spectroscopic metallicities of late-K and M dwarfs spanning 1.5 dex
• CARMENES input catalogue of M dwarfs. I. Low-resolution spectroscopy with CAFOS
• Stellar Diameters and Temperatures V. Eleven Newly Characterized Exoplanet Host Stars
• CARMENES input catalogue of M dwarfs: III. Rotation and activity from high-resolution spectroscopic observations
• HATS-6b: A Warm Saturn Transiting an Early M Dwarf Star, and a Set of Empirical Relations for Characterizing K and M Dwarf Planet Hosts
• Atmospheres from very low-mass stars to extrasolar planets
• M Dwarf Metallicities and Giant Planet Occurrence: Ironing Out Uncertainties and Systematics
• CARMENES input catalogue of M dwarfs II. High-resolution imaging with FastCam
• Stellar parameters of early M dwarfs from ratios of spectral features at optical wavelengths
• Radial velocity signatures of Zeeman broadening
• Chemical Abundances of M-dwarfs from the APOGEE Survey. I. The Exoplanet Hosting Stars Kepler-138 and Kepler-186
• CAFE: Calar Alto Fiber-fed Echelle spectrograph
• A physically motivated and empirically calibrated method to measure effective temperature, metallicity, and Ti abundance of M dwarfs
• Fundamental M-dwarf parameters from high-resolution spectra using PHOENIX ACES models: I. Parameter accuracy and benchmark stars
• The physical mechanism behind M dwarf metallicity indicators and the role of C and O abundances
• Metallicity determination of M dwarfs - Expanded parameter range in metallicity and effective temperature

Cited by in corpus (78)

• Gaia Data Release 3: Astrophysical parameters inference system (Apsis) I -- methods and content overview
• The CARMENES search for exoplanets around M dwarfs: Different roads to radii and masses of the target stars
• Magnetism, rotation, and nonthermal emission in cool stars -- Average magnetic field measurements in 292 M dwarfs
• CARMENES input catalogue of M dwarfs V. Luminosities, colours, and spectral energy distributions
• The CARMENES search for exoplanets around M dwarfs. Two temperate Earth-mass planet candidates around Teegarden's Star
• A candidate super-Earth planet orbiting near the snow line of Barnard's star
• CARMENES input catalogue of M dwarfs: III. Rotation and activity from high-resolution spectroscopic observations
• The CARMENES search for exoplanets around M dwarfs. Activity indicators at visible and near-infrared wavelengths
• The CARMENES search for exoplanets around M dwarfs. Stellar atmospheric parameters of target stars with SteParSyn
• Magnetic fields in M dwarfs from the CARMENES survey
• The CARMENES search for exoplanets around M dwarfs. Guaranteed time observations Data Release 1 (2016-2020)
• The CARMENES search for exoplanets around M dwarfs -- Photospheric parameters of target stars from high-resolution spectroscopy. II. Simultaneous multiwavelength range modeling of activity insensitive lines
• The CARMENES search for exoplanets around M dwarfs. Two planets on the opposite sides of the radius gap transiting the nearby M dwarf LTT 3780
• HADES RV Programme with HARPS-N at TNG XII. The abundance signature of M dwarf stars with planets
• PENELLOPE: the ESO data legacy program to complement the Hubble UV Legacy Library of Young Stars (ULLYSES) I. Survey presentation and accretion properties of Orion OB1 and $\sigma$-Orionis
• RV-detected planets around M dwarfs: Challenges for core accretion models
• Stellar Characterization of M-dwarfs from the APOGEE Survey: A Calibrator Sample for the M-dwarf Metallicities
• A detailed analysis of the Gl 486 planetary system
• The CARMENES search for exoplanets around M dwarfs -- LP 714-47b (TOI 442.01): Populating the Neptune desert
• The CARMENES search for exoplanets around M dwarfs: Nine new double-line spectroscopic binary stars
• Detailed Chemical Abundances for a Benchmark Sample of M Dwarfs from the APOGEE Survey
• Discovery of a hot, transiting, Earth-sized planet and a second temperate, non-transiting planet around the M4 dwarf GJ 3473 (TOI-488)
• The CARMENES search for exoplanets around M dwarfs. Characterization of the nearby ultra-compact multiplanetary system YZ Ceti
• The CARMENES search for exoplanets around M dwarfs -- A deep learning approach to determine fundamental parameters of target stars
• The CARMENES search for exoplanets around M dwarfs: The warm super-Earths in twin orbits around the mid-type M dwarfs Ross 1020 (GJ 3779) and LP 819-052 (GJ 1265)
• A HARPS RV search for planets around young nearby stars
• The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 pc
• Radial velocity photon limits for the dwarf stars of spectral classes F--M
• Estimating the atmospheric properties of 44 M dwarfs from SPIRou spectra
• Evolutionary models for ultracool dwarfs
• Estimating fundamental parameters of nearby M dwarfs from SPIRou spectra
• A sub-Earth-mass planet orbiting Barnard's star
• The CARMENES search for exoplanets around M dwarfs. Two terrestrial planets orbiting G 264-012 and one terrestrial planet orbiting Gl 393
• Effective Temperatures of Low-Mass Stars from High-Resolution H-band Spectroscopy
• Stellar Atmospheric Parameters of M-type Stars from LAMOST DR8
• The CARMENES search for exoplanets around M dwarfs: Not-so-fine hyperfine-split vanadium lines in cool star spectra
• The CARMENES search for exoplanets around M dwarfs: Rubidium abundances in nearby cool stars
• The CARMENES search for exoplanets around M dwarfs. Dynamical characterization of the multiple planet system GJ 1148 and prospects of habitable exomoons around GJ 1148 b
• The CARMENES search for exoplanets around M dwarfs: Spectroscopic orbits of nine M-dwarf multiple systems, including two triples, two brown dwarf candidates, and one close M-dwarf-white dwarf binary
• The KOBE experiment: K-dwarfs Orbited By habitable Exoplanets. Project goals, target selection and stellar characterization
• The SOPHIE search for northern extrasolar planets XV. A Warm Neptune around the M-dwarf Gl378
• The CARMENES search for exoplanets around M dwarfs - The enigmatic planetary system GJ 4276: One eccentric planet or two planets in a 2:1 resonance?
• Comparative high-resolution spectroscopy of M dwarfs -- exploring non-LTE effects
• Two super-Earths at the edge of the habitable zone of the nearby M dwarf TOI-2095
• Physical properties and trigonometric distance of the peculiar dwarf WISE J181005.5$-$101002.3
• ODUSSEAS: Upgraded version with new reference scale and parameter determinations for 82 planet-host M dwarf stars in SWEET-Cat
• The NewEra model grid
• Characterisation of 92 Southern TESS Candidate Planet Hosts and a New Photometric [Fe/H] Relation for Cool Dwarfs
• Stellar Characterization and Radius Inflation of Hyades M Dwarf Stars From the APOGEE Survey
• The CARMENES search for exoplanets around M dwarfs. A super-Earth planet orbiting HD 79211 (GJ 338 B)
• Analysis of the TiO isotopologues in stellar optical spectra
• Precise mass determination for the keystone sub-Neptune planet transiting the mid-type M dwarf G 9-40
• Chemical Properties of the Local Disk and Halo. II. Abundances of 3745 M dwarfs and Subdwarfs from Improved Model Fitting of Low-Resolution Spectra
• The CARMENES search for exoplanets around M dwarfs Detection of a mini-Neptune around LSPM J2116+0234 and refinement of orbital parameters of a super-Earth around GJ 686 (BD+18 3421)
• The CARMENES search for exoplanets around M dwarfs. Diagnostic capabilities of strong K I lines for photosphere and chromosphere
• The CARMENES search for exoplanets around M dwarfs. Chromospheric modeling of M2-3 V stars with PHOENIX
• Estimating $T_{\mathrm{eff}}$, radius and luminosity of M-dwarfs using high resolution optical and NIR spectral features
• Using autoencoders and deep transfer learning to determine the stellar parameters of 286 CARMENES M dwarfs
• A super-Earth on a close-in orbit around the M1V star GJ 740. A HADES and CARMENES collaboration
• Photometric Calibrations of M-dwarf Metallicity with Markov Chain Monte Carlo and Bayesian Inference
• Planetary companions orbiting the M dwarfs GJ 724 and GJ 3988. A CARMENES and IRD collaboration
• Ariel stellar characterisation II. Chemical abundances of carbon, nitrogen, and oxygen for 181 planet-host FGK dwarf stars
• The CARMENES search for exoplanets around M dwarfs. Behaviour of the Paschen lines during flares and quiescence
• Cool and Data-Driven: An Exploration of Optical Cool Dwarf Chemistry with Both Data-Driven and Physical Models
• GJ 357 b: A Super-Earth Orbiting an Extremely Inactive Host Star
• The CARMENES search for exoplanets around M dwarfs -- A deep transfer learning method to determine Teff and [M/H] of target stars
• Measurements of the Ca II infrared triplet emission lines of pre-main-sequence stars
• The CARMENES search for exoplanets around M dwarfs. A sub-Neptunian mass planet in the habitable zone of HN Lib
• Correlating Intrinsic Stellar Parameters with Mg II Self-Reversal Depths
• Performance of the Stellar Abundances and atmospheric Parameters Pipeline adapted for M dwarfs I. Atmospheric parameters from the spectroscopic module
• Rubidium abundances in solar metallicity stars
• Abundance analysis of benchmark M dwarfs
• M Subdwarf Research III. Spectroscopic Diagnostics for Breaking Parameter Degeneracy
• Calibrating the metallicity of M dwarfs in wide physical binaries with F-, G-, and K-primaries -- II: Carbon, oxygen, and odd-Z iron-peak abundances of the primary stars
• Exploring the stellar properties of M dwarfs with high-resolution spectroscopy from the optical to the near-infrared
• Discovery of a transiting hot water-world candidate orbiting Ross 176 with TESS and CARMENES
• Metallicities in M dwarfs: Investigating different determination techniques
• Refined M-type Star Catalog from LAMOST DR10: Measurements of Radial Velocities, $T_{\text{eff}}$, log $g$, [M/H] and [$\alpha$/M]