A sub-Neptune and a non-transiting Neptune-mass companion unveiled by ESPRESSO around the bright late-F dwarf HD 5278 (TOI-130)

Abstract

[Abridged] We exploit the extreme radial velocity (RV) precision of the ultra-stable echelle spectrograph ESPRESSO on the VLT to unveil the physical properties of the transiting sub-Neptune TOI-130 b, uncovered by TESS orbiting the nearby, bright, late F-type star HD 5278 (TOI-130) with a period $P_{\mathrm{b}}=14.3$. We use 43 ESPRESSO high-resolution spectra and broad-band photometry information to derive accurate stellar atmospheric and physical parameters of HD 5278. We exploit the TESS light curve (LC) and spectroscopic diagnostics to gauge the impact of stellar activity on the ESPRESSO RVs. We perform a joint ESPRESSO RVs + TESS LC analysis using fully Bayesian frameworks to determine the system parameters. The updated stellar parameters of HD 5278 are T${}_{\mathrm{eff}}=6203\pm 64$ K, $\log g=4.50\pm 0.11$ dex, [Fe/H]=$-0.12\pm 0.04$ dex, M${}_{\star }=1.126_{-0.035}^{+0.036}$ M${}_{\odot }$ and R${}_{\star }=1.194_{-0.016}^{+0.017}$ R${}_{\odot }$. We determine HD 5278 b's mass and radius to be $M_{\mathrm{b}}=7.8_{-1.4}^{+1.5}$ M${}_{\oplus }$ and $R_{\mathrm{b}}=2.45\pm 0.05$ R${}_{\oplus }$. The derived mean density, ${\varrho }_{\mathrm{b}}=2.9_{-0.5}^{+0.6}$ g cm${}^{-3}$, is consistent with a bulk composition with a substantial ($\sim 30\%$) water mass fraction and a gas envelope comprising $\sim 17\%$ of the measured radius. Given the host brightness and irradiation levels, HD 5278 b is one of the best targets orbiting G-F primaries for follow-up atmospheric characterization measurements with HST and JWST. We discover a second, non-transiting companion in the system, with a period $P_{\mathrm{c}}=40.87_{-0.17}^{+0.18}$ days and a minimum mass $M_{\mathrm{c}}\sin i_{\mathrm{c}}=18.4_{-1.9}^{+1.8}$ M${}_{\oplus }$. We study emerging trends in the growing population of transiting sub-Neptunes, and provide statistical evidence for a low occurrence of close-in, $10-15$ M${}_{\oplus }$ companions around G-F primaries with $T_{\mathrm{eff}}\gtrsim 5500$ K.

References in corpus (132)

• Gaia Data Release 2. Summary of the contents and survey properties
• The Transiting Exoplanet Survey Satellite
• Gaia Data Release 2: The astrometric solution
• Estimating distances from parallaxes IV: Distances to 1.33 billion stars in Gaia Data Release 2
• The generalised Lomb-Scargle periodogram. A new formalism for the floating-mean and Keplerian periodograms
• X-ray spectral modelling of the AGN obscuring region in the CDFS: Bayesian model selection and catalogue
• The California-Kepler Survey. III. A Gap in the Radius Distribution of Small Planets
• Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics
• Planet Occurrence within 0.25 AU of Solar-type Stars from Kepler
• batman: BAsic Transit Model cAlculatioN in Python
• Kepler Presearch Data Conditioning II - A Bayesian Approach to Systematic Error Correction
• A box-fitting algorithm in the search for periodic transits
• Clouds in the atmosphere of the super-Earth exoplanet GJ 1214b
• Elemental Abundance Survey of The Galactic Thick Disk
• Towards Better Age Estimates for Stellar Populations: The Y^2 Isochrones for Solar Mixture
• Kepler Presearch Data Conditioning I - Architecture and Algorithms for Error Correction in Kepler Light Curves
• Most 1.6 Earth-Radius Planets are not Rocky
• Architecture and Dynamics of Kepler's Candidate Multiple Transiting Planet Systems
• The evaporation valley in the Kepler planets
• Gaia Data Release 2: Photometric content and validation
• EXOFAST: A fast exoplanetary fitting suite in IDL
• Rotation Periods of 34,030 Kepler Main-Sequence Stars: The Full Autocorrelation Sample
• Architecture of Kepler's Multi-transiting Systems: II. New investigations with twice as many candidates
• Understanding the Mass-Radius Relation for Sub-Neptunes: Radius as a Proxy for Composition
• Temperate Earth-sized planets transiting a nearby ultracool dwarf star
• Spectroscopic parameters for 451 stars in the HARPS GTO planet search program. Stellar [Fe/H] and the frequency of exo-Neptunes
• A Framework for Prioritizing the TESS Planetary Candidates Most Amenable to Atmospheric Characterization
• Growth Model Interpretation of Planet Size Distribution
• Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program.Galactic stellar populations and planets
• ESPRESSO@VLT -- On-sky performance and first results
• The California Kepler Survey VII. Precise Planet Radii Leveraging Gaia DR2 Reveal the Stellar Mass Dependence of the Planet Radius Gap
• BANYAN. XI. The BANYAN $\Sigma$ multivariate Bayesian algorithm to identify members of young associations within 150 pc
• An asteroseismic view of the radius valley: stripped cores, not born rocky
• Core-powered mass loss and the radius distribution of small exoplanets
• Basic physical parameters of a selected sample of evolved stars
• Revised Catalog of GALEX Ultraviolet Sources. I. The All-sky Survey: GUVcat_AIS
• Sculpting the Valley in the Radius Distribution of Small Exoplanets as a by-product of Planet Formation: The Core-Powered Mass-Loss Mechanism
• How Thermal Evolution and Mass Loss Sculpt Populations of Super-Earths and Sub-Neptunes: Application to the Kepler-11 System and Beyond
• Stellar and substellar companions of nearby stars from Gaia DR2 - Binarity from proper motion anomaly
• Kepler-36: A Pair of Planets with Neighboring Orbits and Dissimilar Densities
• Breaking the Chains: Hot Super-Earth systems from migration and disruption of compact resonant chains
• Helium in the eroding atmosphere of an exoplanet
• A New Family of Planets ? "Ocean Planets"
• Extracting Planet Mass and Eccentricity From TTV data
• Three regimes of extrasolar planets inferred from host star metallicities
• Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2
• A new code for automatic determination of equivalent widths: Automatic Routine for line Equivalent widths in stellar Spectra (ARES)
• Kepler Data Validation I -- Architecture, Diagnostic Tests, and Data Products for Vetting Transiting Planet Candidates
• Compositional diversity in the atmospheres of hot Neptunes, with application to GJ 436b
• Water Vapor and Clouds on the Habitable-Zone Sub-Neptune Exoplanet K2-18b
• Spectroscopic stellar parameters for 582 FGK stars in the HARPS volume-limited sample. Revising the metallicity-planet correlation
• Water Vapour Absorption in the Clear Atmosphere of an exo-Neptune
• Water vapour in the atmosphere of the habitable-zone eight Earth-mass planet K2-18 b
• Compositional imprints in density-distance-time: a rocky composition for close-in low-mass exoplanets from the location of the valley of evaporation
• Ground-based detection of an extended helium atmosphere in the Saturn-mass exoplanet WASP-69b
• Limb darkening and exoplanets: testing stellar model atmospheres and identifying biases in transit parameters
• Hot super-Earths stripped by their host stars
• Formation of planetary systems by pebble accretion and migration: How the radial pebble flux determines a terrestrial-planet or super-Earth growth mode
• Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18
• Planetary nebulae seen with TESS: Discovery of new binary central star candidates from Cycle 1
• Determining stellar macroturbulence using asteroseismic rotational velocities from Kepler
• The Atmospheric Signatures of Super-Earths: How to Distinguish Between Hydrogen-Rich and Hydrogen-Poor Atmospheres
• A Detailed Model Grid for Solid Planets from 0.1 through 100 Earth Masses
• Kepler Data Validation II -- Transit Model Fitting and Multiple-Planet Search
• Spectrally resolved helium absorption from the extended atmosphere of a warm Neptune-mass exoplanet
• The Nature of the Radius Valley: Hints from Formation and Evolution Models
• Ocean Planet or Thick Atmosphere: On the Mass-Radius Relationship for Solid Exoplanets with Massive Atmospheres
• ARES v2 - new features and improved performance
• A generalized bayesian inference method for constraining the interiors of super Earths and sub-Neptunes
• HAT-P-26b: A Neptune-Mass Exoplanet with a Well Constrained Heavy Element Abundance
• Eclipsing Binary Stars as Benchmarks for Trigonometric Parallaxes in the Gaia Era
• Hubble Space Telescope Near-IR Transmission Spectroscopy of the Super-Earth HD 97658b
• Overstable Librations can account for the Paucity of Mean Motion Resonances among Exoplanet Pairs
• TESS Discovery of a Transiting Super-Earth in the $\pi$ Mensae System
• Hydrodynamics of Embedded Planets' First Atmospheres. II. A Rapid Recycling of Atmospheric Gas
• Bayesian distances and extinctions for giants observed by Kepler and APOGEE
• An Excess of Jupiter Analogs in Super-Earth Systems
• Photochemistry in Terrestrial Exoplanet Atmospheres III: Photochemistry and Thermochemistry in Thick Atmospheres on Super Earths and Mini Neptunes
• The Radius Distribution of Planets Around Cool Stars
• Constraining Exoplanet Mass from Transmission Spectroscopy
• The Ages of the Thin Disk, Thick Disk, and the Halo from Nearby White Dwarfs
• AMD-stability and the classification of planetary systems
• The effect of stellar limb darkening values on the accuracy of the planet radii derived from photometric transit observations
• A new method to compute limb-darkening coefficients for stellar atmosphere models with spherical symmetry: the space missions TESS, Kepler, Corot, and MOST
• On The Origins Of Eccentric Close-in Planets
• The interior and atmosphere of the habitable-zone exoplanet K2-18b
• Irradiated ocean planets bridge super-Earth and sub-Neptune populations
• Atmosphere Origins for Exoplanet Sub-Neptunes
• Determining stellar parameters of asteroseismic targets: going beyond the use of scaling relations
• The Precision of Mass Measurements Required for Robust Atmospheric Characterization of Transiting Exoplanets
• A giant impact as the likely origin of different twins in the Kepler-107 exoplanet system
• Revisiting Proxima with ESPRESSO
• An Earth-sized exoplanet with a Mercury-like composition
• Revised mass-radius relationships for water-rich rocky planets more irradiated than the runaway greenhouse limit
• Migration-driven diversity of super-Earth compositions
• Formation of close-in super-Earths in evolving protoplanetary disks due to disk winds
• Rocky super-Earths or waterworlds: the interplay of planet migration, pebble accretion and disc evolution
• Zodiacal Exoplanets in Time (ZEIT) VI: a three-planet system in the Hyades cluster including an Earth-sized planet
• The CORALIE survey for southern extrasolar planets. XVI. Discovery of a planetary system around HD 147018 and of two long period and massive planets orbiting HD 171238 and HD 204313
• A Class of Warm Jupiters with Mutually Inclined, Apsidally Misaligned, Close Friends
• The effects of external planets on inner systems: multiplicities, inclinations, and pathways to eccentric warm Jupiters
• Identifying the best iron-peak and $\alpha$-capture elements for chemical tagging: The impact of the number of lines on measured scatter
• The GAPS programme at TNG XXII. The GIARPS view of the extended helium atmosphere of HD189733 b accounting for stellar activity
• Tidal dissipation and the formation of Kepler near-resonant planets
• High-Resolution Spectroscopy of the Transiting Planet Host Star TrES-1
• Radial velocity confirmation of K2-100b: a young, highly irradiated, and low density transiting hot Neptune
• CKS VIII: Eccentricities of Kepler Planets and Tentative Evidence of a High Metallicity Preference for Small Eccentric Planets
• Quantifying the Bayesian Evidence for a Planet in Radial Velocity Data
• Giant planet formation at the pressure maxima of protoplanetary disks II. A hybrid accretion scenario
• Non-detection of Helium in the Upper Atmospheres of Three Sub-Neptune Exoplanets
• A semi-empirical stability criterion for real planetary systems
• Three Small Super-Earths Transiting the nearby star GJ 9827
• A Joint Mass-Radius-Period Distribution of Exoplanets
• Detectable molecular features above hydrocarbon haze via transmission spectroscopy with JWST: Case studies of GJ 1214b-, GJ 436b-, HD 97658b-, and Kepler-51b-like planets
• Threshold radii of volatile-rich planets
• Improved parameters of seven Kepler giant companions characterized with SOPHIE and HARPS-N
• The Gaia Ultra-Cool Dwarf Sample -- II: Structure at the end of the main sequence
• K2-111: an old system with two planets in near-resonance
• Eyes on K2-3: A system of three likely sub-Neptunes characterized with HARPS-N and HARPS
• Challenges to Constraining Exoplanet Masses via Transmission Spectroscopy
• Sub-Neptune Formation: The View from Resonant Planets
• The correlation between photometric variability and radial velocity jitter, based on TESS and HARPS observations
• Normalized angular momentum deficit: A tool for comparing the violence of the dynamical histories of planetary systems
• TESS Reveals a Short-period Sub-Neptune Sibling (HD 86226c) to a Known Long-period Giant Planet
• First-order mean motion resonances in two-planet systems: general analysis and observed systems
• Migration of Planets Into and Out of Mean Motion Resonances in Protoplanetary Disks: Analytical Theory of Second-Order Resonances
• Unified simulations of planetary formation and atmospheric evolution: Effects of pebble accretion, giant impacts, and stellar irradiations on super-Earth formation
• Detection of Neptune-size planetary candidates with CoRoT data. Comparison with the planet occurrence rate derived from Kepler
• Characterization of the Kepler-101 planetary system with HARPS-N. A hot super-Neptune with an Earth-sized low-mass companion
• Detection and characterization of an ultra-dense sub-Neptune planet orbiting the Sun-like star HD 119130
• Activity time series of old stars from late F to early K IV. Diagnosis from photometry
• Assessing the Interior Structure of Terrestrial Exoplanets with Implications for Habitability

Cited by in corpus (18)

• Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia EDR3 stars brighter than G=18.5
• ExoClock Project III: 450 new exoplanet ephemerides from ground and space observations
• Uncovering the true periods of the young sub-Neptunes orbiting TOI-2076
• An unusually low-density super-Earth transiting the bright early-type M-dwarf GJ 1018 (TOI-244)
• New Perspectives on the Exoplanet Radius Gap from a Mathematica Tool and Visualized Water Equation of State
• HD 23472: A multi-planetary system with three super-Earths and two potential super-Mercuries
• The HD 137496 system: A dense, hot super-Mercury and a cold Jupiter
• Planetary system around LTT 1445A unveiled by ESPRESSO: Multiple planets in a triple M-dwarf system
• Revisiting WASP-47 with ESPRESSO and TESS
• HD22496b: the first ESPRESSO standalone planet discovery
• Exoplanet atmosphere evolution: emulation with neural networks
• Three Saturn-mass planets transiting F-type stars revealed with TESS and HARPS
• NIGHT: a compact, near-infrared, high-resolution spectrograph to survey helium in exoplanet systems
• Two neighbours of the ultra-short-period Earth-sized planet K2-157 b in the warm Neptunian savanna
• L 363-38 b: a planet newly discovered with ESPRESSO orbiting a nearby M dwarf star
• The Occurrence-weighted Median Planets Discovered by Transit Surveys Orbiting Solar-type Stars and Their Implications for Planet Formation and Evolution
• The TESS-Keck Survey. XI. Mass Measurements for Four Transiting sub-Neptunes orbiting K dwarf TOI-1246
• On the Need for a Classification System for Consistent Characterization of the Composition of Planetary Bodies