Mass and density of the transiting hot and rocky super-Earth LHS 1478 b (TOI-1640 b)

Abstract

One of the main objectives of the Transiting Exoplanet Survey Satellite ({TESS}) mission is the discovery of small rocky planets around relatively bright nearby stars. Here, we report the discovery and characterization of the transiting super-Earth planet orbiting LHS~1478 (TOI-1640). The star is an inactive red dwarf ($J\sim 9.6$\,mag and spectral type m3\,V) with mass and radius estimates of $0.20\pm 0.01$\,$M_{\odot }$ and $0.25\pm 0.01$\,$R_{\odot }$, respectively, and an effective temperature of $3381\pm 54$\,K.It was observed by \tess in four sectors. These data revealed a transit-like feature with a period of 1.949 days. We combined the TESS data with three ground-based transit measurements, 57 radial velocity (RV) measurements from CARMENES, and 13 RV measurements from IRD, determining that the signal is produced by a planet with a mass of $2.33_{-0.20}^{+0.20}$\,$M_{\oplus }$ and a radius of $1.24_{-0.05}^{+0.05}$\,$R_{\oplus }$. The resulting bulk density of this planet is 6.67\,g\,cm${}^{-3}$, which is consistent with a rocky planet with an Fe- and MgSiO${}_3$-dominated composition. Although the planet would be too hot to sustain liquid water on its surface (its equilibrium temperature is about $\sim$595\,K, suggesting a Venus-like atmosphere), spectroscopic metrics based on the capabilities of the forthcoming James Webb Space Telescope and the fact that the host star is rather inactive indicate that this is one of the most favorable known rocky exoplanets for atmospheric characterization.

arXiv comment14 pages, 10 figures, 6 tables, accepted for publication in A&A

References in corpus (66)

• The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms
• Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1
• A terrestrial planet candidate in a temperate orbit around Proxima Centauri
• Astrophysics Source Code Library
• Las Cumbres Observatory Global Telescope Network
• Gaia Early Data Release 3: The astrometric solution
• Kepler Presearch Data Conditioning II - A Bayesian Approach to Systematic Error Correction
• Fast and scalable Gaussian process modeling with applications to astronomical time series
• The Revised TESS Input Catalog and Candidate Target List
• A box-fitting algorithm in the search for periodic transits
• Efficient, uninformative sampling of limb darkening coefficients for two-parameter laws
• On the Unique Solution of Planet and Star Parameters from an Extrasolar Planet Transit Light Curve
• The TESS Input Catalog and Candidate Target List
• AstroImageJ: Image Processing and Photometric Extraction for Ultra-Precise Astronomical Light Curves
• AstroImageJ: Image Processing and Photometric Extraction for Ultra-Precise Astronomical Light Curves (Expanded Edition)
• A Framework for Prioritizing the TESS Planetary Candidates Most Amenable to Atmospheric Characterization
• Growth Model Interpretation of Planet Size Distribution
• petitRADTRANS: a Python radiative transfer package for exoplanet characterization and retrieval
• Spectrum radial velocity analyser (SERVAL). High-precision radial velocities and two alternative spectral indicators
• Mass-Radius Relation for Rocky Planets based on PREM
• The Transit Light Source Effect: False Spectral Features and Incorrect Densities for M-dwarf Transiting Planets
• Juliet: a versatile modelling tool for transiting and non-transiting exoplanetary systems
• PandExo: A Community Tool for Transiting Exoplanet Science with JWST & HST
• Kepler Data Validation I -- Architecture, Diagnostic Tests, and Data Products for Vetting Transiting Planet Candidates
• Limb and gravity-darkening coefficients for the TESS satellite at several metallicities, surface gravities, and microturbulent velocities
• The rotation and Galactic kinematics of mid M dwarfs in the Solar Neighborhood
• Planetary nebulae seen with TESS: Discovery of new binary central star candidates from Cycle 1
• The CARMENES search for exoplanets around M dwarfs: High-resolution optical and near-infrared spectroscopy of 324 survey stars
• Transit Least Squares: Optimized transit detection algorithm to search for periodic transits of small planets
• Kepler Data Validation II -- Transit Model Fitting and Multiple-Planet Search
• A rocky planet transiting a nearby low-mass star
• Aerosol Composition of Hot Giant Exoplanets Dominated by Silicates and Hydrocarbon Hazes
• The CARMENES search for exoplanets around M dwarfs: Different roads to radii and masses of the target stars
• K2SC: Flexible systematics correction and detrending of K2 light curves using Gaussian Process regression
• A public HARPS radial velocity database corrected for systematic errors
• Transit Detection in the MEarth Survey of Nearby M Dwarfs: Bridging the Clean-First, Search-Later Divide
• 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
• Flat-relative optimal extraction. A quick and efficient algorithm for stabilised spectrographs
• CARMENES input catalogue of M dwarfs: III. Rotation and activity from high-resolution spectroscopic observations
• High-resolution imaging of $Kepler$ planet host candidates. A comprehensive comparison of different techniques
• A framework to combine low- and high-resolution spectroscopy for the atmospheres of transiting exoplanets
• Planetary system around the nearby M dwarf GJ 357 including a transiting, hot, Earth-sized planet optimal for atmospheric characterization
• Correcting HIRES radial velocities for small systematic errors
• The CARMENES search for exoplanets around M dwarfs. Activity indicators at visible and near-infrared wavelengths
• Multiplicity in transiting planet host stars. A Lucky Imaging study of Kepler candidates
• The Monitor project: Data processing and lightcurve production
• 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
• A nearby transiting rocky exoplanet that is suitable for atmospheric investigation
• Photochemical Haze Formation in the Atmospheres of super-Earths and mini-Neptunes
• Precision radial velocity measurements by the forward-modeling technique in the near-infrared
• Seeing above the Clouds with High Resolution Spectroscopy
• A hot terrestrial planet orbiting the bright M dwarf L 168-9 unveiled by TESS
• The CARMENES search for exoplanets around M dwarfs. Measuring precise radial velocities in the near infrared: the example of the super-Earth CD Cet b
• The CARMENES search for exoplanets around M dwarfs. Three temperate to warm super-Earths
• From cold to hot irradiated gaseous exoplanets: Fingerprints of chemical disequilibrium in atmospheric spectra
• The CARMENES search for exoplanets around M dwarfs -- LP 714-47b (TOI 442.01): Populating the Neptune desert
• Precise mass and radius of a transiting super-Earth planet orbiting the M dwarf TOI-1235: a planet in the radius gap?
• From cold to hot irradiated gaseous exoplanets: Toward an observation-based classification scheme
• Discovery of a hot, transiting, Earth-sized planet and a second temperate, non-transiting planet around the M4 dwarf GJ 3473 (TOI-488)
• AstraLux - the Calar Alto 2.2-m telescope Lucky Imaging camera
• 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)
• LHS 1815b: The First Thick-Disk Planet Detected By TESS
• The role of clouds on the depletion of methane and water dominance in the transmission spectra of irradiated exoplanets
• TOI-1728b: The Habitable-zone Planet Finder confirms a warm super Neptune orbiting an M dwarf host

Cited by in corpus (21)

• The CARMENES search for exoplanets around M dwarfs. Guaranteed time observations Data Release 1 (2016-2020)
• A More Precise Mass for GJ 1214 b and the Frequency of Multi-Planet Systems Around Mid-M Dwarfs
• TOI-561 b: A Low Density Ultra-Short Period "Rocky" Planet around a Metal-Poor Star
• The HD 260655 system: Two rocky worlds transiting a bright M dwarf at 10 pc
• Hot Rocks Survey I : A possible shallow eclipse for LHS 1478 b
• Discovery and mass measurement of the hot, transiting, Earth-sized planet GJ 3929 b
• TESS discovery of a sub-Neptune orbiting a mid-M dwarf TOI-2136
• GJ 3090 b: one of the most favourable mini-Neptune for atmospheric characterisation
• GJ 806 (TOI-4481): A bright nearby multi-planetary system with a transiting hot, low-density super-Earth
• The LHS 1678 System: Two Earth-Sized Transiting Planets and an Astrometric Companion Orbiting an M Dwarf Near the Convective Boundary at 20 pc
• The Atmospheres of Rocky Exoplanets II. Influence of surface composition on the diversity of cloud condensates
• TOI-1801 b: A temperate mini-Neptune around a young M0.5 dwarf
• A multi-planetary system orbiting the early-M dwarf TOI-1238
• Hundreds of TESS exoplanets might be larger than we thought
• J-PLUS: Support Vector Regression to Measure Stellar Parameters
• Two sub-Neptunes around the M dwarf TOI-1470
• Follow-up of non-transiting planets detected by Kepler. Confirmation of three hot-Jupiters and validation of three other planets
• Uniform Reanalysis of JWST MIRI 15μm Exoplanet Eclipse Observations using Frame-Normalized Principal Component Analysis
• No Robust Statistical Evidence for a Population of Water Worlds in a 2025 Sample of Planets Orbiting M Stars
• GJ 3929 b as the First Complete Rocky Worlds DDT Data Set
• The CARMENES search for exoplanets around M dwarfs. A homogeneous catalogue of projected rotational velocities accounting for limb-darkening