Inflated hot Jupiters: Inferring average atmospheric velocity via Ohmic models coupled with internal dynamo evolution

Abstract

The inflated radii observed in hundreds of hot Jupiters (HJ) represent a long-standing open issue. In this study, we quantitatively investigate this phenomenon within the framework of Ohmic dissipation arising from magnetic induction in the atmosphere, one of the most promising mechanisms for explaining the radius anomaly. We simulate the evolution of irradiated giant planets with MESA, spanning the observed range of masses and equilibrium temperatures, incorporating an internal source of Ohmic dissipation that extends to deep layers of the envelope. We infer average atmospheric wind intensities, averaged in the region $p<10$ bar, in the range 0.01-1 km/s in order to reproduce the range of observed radii, decreasing roughly linearly with planetary mass, and much more steeply with equilibrium temperature. This is consistent with the expected effects of magnetic drag from the induced field, which is higher for more intense irradiation, via conductivity, and for larger masses, which have higher dynamo fields. Due to the evolution of the dynamo field and the proportionality of the induced currents on it, the Ohmic efficiency typically decreases by at least one order of magnitude from 0.1 to 10 Gyr, at contrast with the common assumption of a constant-in-time value. Notably, the extent of the main convective region, and the associated heat flux supporting the dynamo, is reduced in the presence of strong Ohmic dissipation, which in turn depends on the dynamo field strength, generating a non-trivial coupling of the latter with the atmospheric induction, potentially leading to an oscillatory behaviour of the field strength. These findings remain generally valid even when accounting for a long-term increase in the main-sequence host star luminosity, although this case can more readily lead to HJ re-inflation, consistent with previous studies.

arXiv commentAccepted for publication in A&A main journal. 22 pages, 14 figures, 1 table. Comments welcome

References in corpus (101)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• Modules for Experiments in Stellar Astrophysics (MESA): Convective Boundaries, Element Diffusion, and Massive Star Explosions
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• The Dartmouth Stellar Evolution Database
• Planetary Radii across Five Orders of Magnitude in Mass and Stellar Insolation: Application to Transits
• A Unified Theory for the Atmospheres of the Hot and Very Hot Jupiters: Two Classes of Irradiated Atmospheres
• Atmospheric Circulation and Tides of "51Peg b-like" Planets
• Atmospheric circulation of hot Jupiters: Coupled radiative-dynamical general circulation model simulations of HD 189733b and HD 209458b
• Modules for Experiments in Stellar Astrophysics (MESA): Time-Dependent Convection, Energy Conservation, Automatic Differentiation, and Infrastructure
• On the radiative equilibrium of irradiated planetary atmospheres
• The Mass-Metallicity Relation for Giant Planets
• Comparing Jupiter interior structure models to Juno gravity measurements and the role of a dilute core
• Possible Solutions to the Radius Anomalies of Transiting Giant Planets
• 3D mixing in hot Jupiter atmospheres. I. application to the day/night cold trap in HD 209458b
• Inflating Hot Jupiters With Ohmic Dissipation
• Atmospheres of low-mass planets: the "boil-off"
• Atmospheric circulation of tidally locked exoplanets: a suite of benchmark tests for dynamical solvers
• Constraints on Deep-seated Zonal Winds Inside Jupiter and Saturn
• On the Anomalous Radii of the Transiting Extrasolar Planets
• Heat transport in giant (exo)planets: a new perspective
• Magnetic Drag on Hot Jupiter Atmospheric Winds
• Bayesian Analysis of Hot Jupiter Radius Anomalies: Evidence for Ohmic Dissipation?
• Atmospheric Heat Redistribution on Hot Jupiters
• Electronic transport coefficients from ab initio simulations and application to dense liquid hydrogen
• New models of Jupiter in the context of Juno and Galileo
• Atmospheric Dynamics of Hot Exoplanets
• Three-Dimensional Atmospheric Circulation Models of HD 189733b and HD 209458b with Consistent Magnetic Drag and Ohmic Dissipation
• A General Circulation Model for Gaseous Exoplanets with Double-Gray Radiative Transfer
• Increased Heat Transport in Ultra-Hot Jupiter Atmospheres Through H${}_2$ Dissociation/Recombination
• Atmospheric Dynamics of Short-period Extra Solar Gas Giant Planets I: Dependence of Night-Side Temperature on Opacity
• The Atmospheric Circulation of the Hot Jupiter WASP-43b: Comparing Three-Dimensional Models to Spectrophotometric Data
• A magnetic field evolution scenario for brown dwarfs and giant planets
• Effects of compressibility on driving zonal flow in gas giants
• Predicting low-frequency radio fluxes of known extrasolar planets
• The Effects of Irradiation on Hot Jovian Atmospheres: Heat Redistribution and Energy Dissipation
• Evolution of Ohmically Heated Hot Jupiters
• Advection of potential temperature in the atmosphere of irradiated exoplanets: a robust mechanism to explain radius inflation
• Ohmic Dissipation in the Atmospheres of Hot Jupiters
• Magnetic Scaling Laws for the Atmospheres of Hot Giant Exoplanets
• The long egress of GJ~436b's giant exosphere
• Magnetic field strengths of hot Jupiters from signals of star-planet interactions
• Layered convection as the origin of Saturn's luminosity anomaly
• The Intrinsic Temperature and Radiative-Convective Boundary Depth in the Atmospheres of Hot Jupiters
• Auroral radio emission from late L and T dwarfs: A new constraint on dynamo theory in the substellar regime
• Magnetic Effects in Hot Jupiter Atmospheres
• The Mechanical Greenhouse: Burial of Heat by Turbulence in Hot Jupiter Atmospheres
• Magnetohydrodynamic Simulations of the Atmosphere of HD 209458b
• Magnetospheric Radio Emission from Extrasolar Giant Planets: The Role of the Host Stars
• The search for radio emission from the exoplanetary systems 55 Cancri, $\upsilon$ Andromedae, and $\tau$ Boötis using LOFAR beam-formed observations
• On the Occurrence Rate of Hot Jupiters in Different Stellar Environments
• The Strongest Magnetic Fields on the Coolest Brown Dwarfs
• Re-inflated Warm Jupiters Around Red Giants
• Factors Affecting the Radii of Close-in Transiting Exoplanets
• New Avenues for Thermal Inversions in hot Jupiters
• Mass-Loss Evolution of Close-In Exoplanets: Evaporation of Hot Jupiters and the Effect on Population
• Magnetically Controlled Circulation on Hot Extrasolar Planets
• First principles simulations of dense hydrogen
• Estimating the magnetic field strength in hot Jupiters
• Helium abundance in a sample of cool stars: measurements from asteroseismology
• Explaining Jupiter's magnetic field and equatorial jet dynamics
• Thermal Processes Governing Hot-Jupiter Radii
• Evidence of Three Mechanisms Explaining the Radius Anomaly of Hot Jupiters
• Ohmic Dissipation in the Interiors of Hot Jupiters
• Extended Heat Deposition in Hot Jupiters: Application to Ohmic Heating
• Investigating hot-Jupiter inflated radii with hierarchical Bayesian modelling
• HAT-P-65b and HAT-P-66b: Two Transiting Inflated Hot Jupiters and Observational Evidence for the Re-Inflation of Close-In Giant Planets
• Ohmic Heating Suspends, not Reverses, the Cooling Contraction of Hot Jupiters
• Hot-Jupiter Inflation due to Deep Energy Deposition
• Circulation and Dissipation on Hot Jupiters
• Structure and Evolution of Internally Heated Hot Jupiters
• Atmospheric Circulations of Hot Jupiters as Planetary Heat Engines
• High-energy irradiation and mass loss rates of hot Jupiters in the solar neighborhood
• Consistent scaling laws in anelastic spherical shell dynamos
• Stable stratification promotes multiple zonal jets in a turbulent Jovian dynamo model
• Surprisingly Weak Magnetism on Young Accreting Brown Dwarfs
• Slow Cooling and Fast Reinflation for Hot Jupiters
• Electrodynamics on extrasolar giant planets
• The hottest hot Jupiters may host Atmospheric Dynamos
• Removal of Hot Saturns in Mass-Radius Plane by Runaway Mass Loss
• Re-inflation of warm and hot Jupiters
• Dynamo Action of Jupiter's Zonal Winds
• Effects of a radially varying electrical conductivity on 3D numerical dynamos
• H- and Dissociation in Ultra-hot Jupiters: A Retrieval Case Study of WASP-18b
• Characterising Jupiter's dynamo radius using its magnetic energy spectrum
• Thermo-Resistive Instability of Hot Planetary Atmospheres
• Dynamo Action in the Steeply Decaying Conductivity Region of Jupiter-like Dynamo Models
• Ionization and transport in partially ionized multicomponent plasmas: Application to atmospheres of hot Jupiters
• Magnetic induction processes in Hot Jupiters, application to KELT-9b
• Follow-up LOFAR observations of the $\tau$ Boötis exoplanetary system
• Shallowness of circulation in hot Jupiters -- Advancing the Ohmic dissipation model
• A Global Simulation of the Dynamo, Zonal Jets, and Vortices on Saturn
• Unraveling the evolution of hot Jupiter systems under the effect of tidal and magnetic interactions and mass loss
• Magnetic Field Evolution of Hot Exoplanets
• Magnetic winding and turbulence in ultra-hot Jupiters
• Variability from thermo-resistive instability in the atmospheres of hot jupiters
• Electrical Conductivity of Warm Dense Hydrogen from Ohm's Law and Time-Dependent Density Functional Theory
• Planetary Dynamos in Evolving Cold Gas Giants
• Atmospheric heat redistribution effect on Emission spectra of Hot-Jupiters
• Effective drag in rotating, poorly conducting plasma turbulence

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