The Planetary Accretion Shock. III. Smoothing-free 2.5D simulations and calculation of H alpha emission

Abstract

Surveys have looked for H alpha emission from accreting gas giants but found very few objects. Analyses of the detections and non-detections have assumed that the entire gas flow feeding the planet is in radial free-fall. However, hydrodynamical simulations suggest that this is far from reality. We calculate the H alpha emission from multidimensional accretion onto a gas giant, following the gas flow from Hill-sphere scales down to the circumplanetary disc (CPD) and the planetary surface. We perform azimuthally-symmetric radiation-hydrodynamics simulations around the planet and use modern tabulated gas and dust opacities. Crucially, contrasting with most previous simulations, we do not smooth the gravitational potential and do follow the flow down to the planetary surface, where grid cells are 0.01 Jupiter radii small radially. We find that only roughly one percent of the net gas inflow into the Hill sphere reaches directly the planet. As expected for ballistic infall trajectories, most of the gas falls at too large a distance on the CPD to generate H alpha. Including radiation transport removes the high-velocity sub-surface flow previously seen in hydrodynamics-only simulations, so that only the free planet surface and the inner regions of the CPD emit substantially H alpha. Unless magnetospheric accretion, which we neglect here, additionally produces H alpha, the corresponding H alpha production efficiency is much smaller than usually assumed, which needs to be taken into account when analysing (non-)detection statistics.

arXiv commentMain text: 16 pages, 7 figures; appendices: 4 pages, 4 figures; references: 1.7 pages. Printed at ApJ on 2023 July 20th. Version 4: This information and correcting R_Hill -> R_Jup (obvious) in the axis labels of Fig. 9

References in corpus (92)

• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• PLUTO: a Numerical Code for Computational Astrophysics
• Discovery of a planetary-mass companion within the gap of the transition disk around PDS 70
• Rosseland and Planck Mean Opacities for Protoplanetary Discs
• On the Luminosity of Young Jupiters
• The PLUTO Code for Adaptive Mesh Computations in Astrophysical Fluid Dynamics
• The Gemini Planet Imager Exoplanet Survey: Giant Planet and Brown Dwarf Demographics From 10-100 AU
• Two accreting protoplanets around the young star PDS 70
• Models of the in situ formation of detected extrasolar giant planets
• Characterization of exoplanets from their formation I: Models of combined planet formation and evolution
• Characterization of exoplanets from their formation II: The planetary mass-radius relationship
• Orbital and atmospheric characterization of the planet within the gap of the PDS 70 transition disk
• MHD Simulations of Disk-Magnetized Star Interactions in Quiescent Regime: Funnel Flows and Angular Momentum Transport
• Radial migration of gap-opening planets in protoplanetary disks. I. The case of a single planet
• The Shape of the Inner Rim in Proto-Planetary Disks
• The SPHERE infrared survey for exoplanets (SHINE). III. The demographics of young giant exoplanets below 300 au with SPHERE
• Distribution of Accreting Gas and Angular Momentum onto Circumplanetary Disks
• The New Generation Planetary Population Synthesis (NGPPS). I. Bern global model of planet formation and evolution, model tests, and emerging planetary systems
• Accreting Circumplanetary Disks: Observational Signatures
• Magellan Adaptive Optics Imaging of PDS 70: Measuring the Mass Accretion Rate of a Young Giant Planet within a Gapped Disk
• Circumplanetary disc properties obtained from radiation hydrodynamical simulations of gas accretion by protoplanets
• Images of Embedded Jovian Planet Formation At A Wide Separation Around AB Aurigae
• Gas disks to gas giants: Simulating the birth of planetary systems
• Reduced gas accretion on super-Earths and ice giants
• Gas accretion onto planetary cores: three-dimensional self-gravitating radiation hydrodynamical calculations
• Constraining the Nature of the PDS 70 Protoplanets with VLTI/GRAVITY
• Hydrodynamics of embedded planets' first atmospheres - III. The role of radiation transport for super-Earth planets
• Fast and accurate frequency-dependent radiation transport for hydrodynamics simulations in massive star formation
• On the Terminal Rotation Rates of Giant Planets
• Luminosity of young Jupiters revisited. Massive cores make hot planets
• Including Dust Coagulation in Hydrodynamic Models of Protoplanetary Disks: Dust Evolution in the Vicinity of a Jupiter-mass Planet
• Angular Momentum Accretion onto a Gas Giant Planet
• Confidence Level and Sensitivity Limits in High Contrast Imaging
• A search for accreting young companions embedded in circumstellar disks: High-contrast H$\alpha$ imaging with VLT/SPHERE
• Suppression of atmospheric recycling of planets embedded in a protoplanetary disc by buoyancy barrier
• Theoretical Model of Hydrogen Line Emission from Accreting Gas Giants
• Modeling of deep gaps created by giant planets in protoplanetary discs
• Perturbers: SPHERE detection limits to planetary-mass companions in protoplanetary disks
• Evolution of Gas Giant Entropy During Formation by Runaway Accretion
• The growth and hydrodynamic collapse of a protoplanet envelope
• Hubble Space Telescope UV and H$\alpha$ Measurements of the Accretion Excess Emission from the Young Giant Planet PDS 70 b
• Circumplanetary Disk Dynamics in the Isothermal and Adiabatic Limits
• Effects of the Planetary Temperature on the Circumplanetary Disk and on the Gap
• Quasi-static contraction during runaway gas accretion onto giant planets
• Magnetospheric Accretion as a Source of H$\alpha$ Emission from Proto-planets around PDS 70
• Observability of Forming Planets and their Circumplanetary Disks II. -- SEDs and Near-Infrared Fluxes
• On the Mass Function, Multiplicity, and Origins of Wide-Orbit Giant Planets
• The widest H$\alpha$ survey of accreting protoplanets around nearby transition disks
• The Planetary Accretion Shock: I. Framework for Radiation-hydrodynamical Simulations and First Results
• The Planetary Accretion Shock. II. Grid of Post-Shock Entropies and Radiative Shock Efficiencies for Non-Equilibrium Radiation Transport
• Mean gas opacity for circumstellar environments and equilibrium temperature degeneracy
• Comparison of planetary Hα-emission models: A new correlation with accretion luminosity
• Global 3D radiation-hydrodynamic simulations of gas accretion: The opacity dependent growth of Saturn-mass planets
• Meridional Circulation of Dust and Gas in the Circumstellar Disk: Delivery of Solids onto the Circumplanetary Region
• As the Worlds Turn: Constraining Spin Evolution in the Planetary-Mass Regime
• Strong H$\alpha$ emission and signs of accretion in a circumbinary planetary mass companion from MUSE
• Accretion in giant planet circumplanetary disks
• Detectability of embedded protoplanets from hydrodynamical simulations
• Hydrogen recombination line luminosities and -variability from forming planets
• Accreting protoplanets: Spectral signatures and magnitude of gas and dust extinction at H alpha
• HST/WFC3 H$\alpha$ Direct-Imaging Detection of a Point-like Source in the Disk Cavity of AB Aur
• Envelopes of embedded super-Earths II. Three-dimensional isothermal simulations
• Steady State by Recycling prevents Premature Collapse of Protoplanetary Atmospheres
• Near-infrared Accretion Signatures from the Circumbinary Planetary Mass Companion Delorme 1 (AB)b
• On the structure and mass delivery towards circumplanetary discs
• The Giant Accreting Protoplanet Survey (GAPlanetS) -- Results from a Six Year Campaign to Image Accreting Protoplanets
• The Planetary Luminosity Problem: "Missing Planets" and the Observational Consequences of Episodic Accretion
• Searching for proto-planets with MUSE
• Planet migration, resonant locking and accretion streams in PDS70: Comparing models and data
• Possible Signatures of Magnetospheric Accretion onto Young Giant Planets
• Makemake + Sedna: A Continuum Radiation Transport and Photoionization Framework for Astrophysical Newtonian Fluid Dynamics
• Recycling of the first atmospheres of embedded planets: Dependence on core mass and optical depth
• Searching for H${}_{\alpha }$-emitting sources in the gaps of five transitional disks. SPHERE/ZIMPOL high-contrast imaging
• Resolved near-UV hydrogen emission lines at 40-Myr super-Jovian protoplanet Delorme 1 (AB)b: Indications of magnetospheric accretion
• Chronostar. II. Kinematic age and substructure of the Scorpius-Centaurus OB2 association
• Hydrodynamic Model of H$\alpha$ Emission from Accretion Shocks of Proto-Giant Planet and Circumplanetary Disk
• The Separation and H-alpha Contrasts of Massive Accreting Planets in the Gaps of Transitional Disks: Predicted H-alpha Protoplanet Yields for Adaptive Optics Surveys
• The 3D dust and opacity distribution of protoplanets in multi-fluid global simulations
• Boundary Layer Circumplanetary Accretion: How Fast Could an Unmagnetized Planet Spin Up Through Its Disk?
• Efficiently Imaging Accreting Protoplanets from Space: Reference Star Differential Imaging of the PDS 70 Planetary System using the HST/WFC3 Archival PSF Library
• Keck/OSIRIS Pa$\beta$ high-contrast imaging and updated constraints on PDS~70b
• Envelopes of embedded super-Earths I. Two-dimensional simulations
• The vertical structure of the boundary layer around compact objects
• Search for exoplanets and brown dwarfs with VLBI
• Gas accretion onto Jupiter mass planets in discs with laminar accretion flows
• The Dynamic Proto-atmospheres around Low-Mass Planets with Eccentric Orbits
• Magnetic Fields and Accreting Giant Planets around PDS 70
• Boundary Layers of Circumplanetary Disks around Spinning Planets I. Effects of Rossby Waves
• Delivery of gas onto the circumplanetary disk of giant planets: Planetary-mass dependence of the source region of accreting gas and mass accretion rate
• The Visible Integral-field Spectrograph eXtreme (VIS-X): high-resolution spectroscopy with MagAO-X
• Size-selective accretion of dust onto CPDs: Low CPD masses and filtration of larger grains
• Planetary Accretion Shocks with a Realistic Equation of State

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