Observational Signatures of Tightly Wound Spirals Driven by Buoyancy Resonances in Protoplanetary Disks

Abstract

Besides the spirals induced by the Lindblad resonances, planets can generate a family of tightly wound spirals through buoyancy resonances. The excitation of buoyancy resonances depends on the thermal relaxation timescale of the gas. By computing timescales of various processes associated with thermal relaxation, namely, radiation, diffusion, and gas-dust collision, we show that the thermal relaxation in protoplanetary disks' surface layers ($Z/R\gtrsim 0.1$) and outer disks ($R\gtrsim 100$ au) is limited by infrequent gas-dust collisions. The use of isothermal equation of state or rapid cooling, common in protoplanetary disk simulations, is therefore not justified. Using three-dimensional hydrodynamic simulations, we show that the collision-limited slow thermal relaxation provides favorable conditions for buoyancy resonances to develop. Buoyancy resonances produce predominantly vertical motions, whose magnitude at the ${}^{12}$CO emission surface is of order of $100{\mathrm{m}\mathrm{s}}^{-1}$ for Jovian-mass planets, sufficiently large to detect using molecular line observations with ALMA. We generate synthetic observations and describe characteristic features of buoyancy resonances in Keplerian-subtracted moment maps and velocity channel maps. Based on the morphology and magnitude of the perturbation, we propose that the tightly wound spirals observed in TW Hya could be driven by a (sub-)Jovian-mass planet at 90 au. We discuss how non-Keplerian motions driven by buoyancy resonances can be distinguished from those driven by other origins. We argue that observations of multiple lines tracing different heights, with sufficiently high spatial/spectral resolution and sensitivity to separate the emission arising from the near and far sides of the disk, will help constrain the origin of non-Keplerian motions.

arXiv commentAccepted for publication in ApJ, 30 pages, 23 figures, simulated data cubes are available at https://zenodo.org/record/4361639

References in corpus (89)

• Interstellar Dust Grains
• Estimating distances from parallaxes IV: Distances to 1.33 billion stars in Gaia Data Release 2
• Spectral Energy Distributions of T Tauri Stars With Passive Circumstellar Disks
• First Results from High Angular Resolution ALMA Observations Toward the HL Tau Region
• The Disk Substructures at High Angular Resolution Project (DSHARP): I. Motivation, Sample, Calibration, and Overview
• Gas- and dust evolution in protoplanetary disks
• Accretion Disks around Young Objects. I. The Detailed Vertical Structure
• FARGO: a fast eulerian transport algorithm for differentially rotating disks
• Ringed Substructure and a Gap at 1 AU in the Nearest Protoplanetary Disk
• The photodissociation and chemistry of CO isotopologues: applications to interstellar clouds and circumstellar disks
• A comparative study of disc-planet interaction
• Linear and nonlinear evolution of the vertical shear instability in accretion discs
• The effect of dust settling on the appearance of protoplanetary disks
• Discovery of Small-Scale Spiral Structures in the Disk of SAO 206462 (HD 135344B): Implications for the Physical State of the Disk from Spiral Density Wave Theory
• Zonal Flows and Long-Lived Axisymmetric Pressure Bumps in Magnetorotational Turbulence
• Gaps, Rings, and Non-Axisymmetric Structures in Protoplanetary Disks - From Simulations to ALMA Observations
• An Old Disk That Can Still Form a Planetary System
• The Disk Substructures at High Angular Resolution Project (DSHARP): V. Interpreting ALMA maps of protoplanetary disks in terms of a dust model
• Disks ARound TTauri Stars with Sphere (DARTTS-S) I: Sphere / IRDIS Polarimetric Imaging of 8 prominent TTauri Disks
• Spiral Density Waves in a Young Protoplanetary Disk
• Asymmetric features in the protoplanetary disk MWC758
• Kinematic evidence for an embedded protoplanet in a circumstellar disc
• The TW Hya Disk at 870 microns: Comparison of CO and Dust Radial Structures
• FARGO3D: A new GPU-oriented MHD code
• Spiral Arms in the Asymmetrically Illuminated Disk of MWC 758 and Constraints on Giant Planets
• Direct Imaging of Fine Structures in Giant Planet Forming Regions of the Protoplanetary Disk around AB Aurigae
• A Spatially Resolved Vertical Temperature Gradient in the HD 163296 Disk
• Turbulence in the TW Hya Disk
• The Radial Distribution of H2 and CO in TW Hya as Revealed by Resolved ALMA Observations of CO Isotopologues
• Three radial gaps in the disk of TW Hydrae imaged with SPHERE
• Shadows and spirals in the protoplanetary disk HD 100453
• The Structure of Spiral Shocks Excited by Planetary-mass Companions
• Volatile carbon locking and release in protoplanetary disks. A study of TW Hya and HD 100546
• Kinematic detection of a planet carving a gap in a protoplanetary disc
• The Disk Substructures at High Angular Resolution Project (DSHARP): III. Spiral Structures in the Millimeter Continuum of the Elias 27, IM Lup, and WaOph 6 Disks
• Measuring Turbulence in TW Hya with ALMA: Methods and Limitations
• On the wake generated by a planet in a disc
• Cooling Requirements for the Vertical Shear Instability in Protoplanetary Disks
• Convective Overstability in radially stratified accretion disks under thermal relaxation
• Nine localised deviations from Keplerian rotation in the DSHARP circumstellar disks: Kinematic evidence for protoplanets carving the gaps
• CO and dust properties in the TW Hya disk from high-resolution ALMA observations
• Mass inventory of the giant-planet formation zone in a solar nebula analog
• Flybys in protoplanetary discs: I. Gas and dust dynamics
• Zombie Vortex Instability I: A Purely Hydrodynamic Instability to Resurrect the Dead Zones of Protoplanetary Disks
• Emission Lines from the Gas Disk around TW Hydra and the Origin of the Inner Hole
• Planet Formation in AB Aurigae: Imaging of the inner gaseous Spirals observed inside the Dust Cavity
• The 0.5-2.22-micron Scattered Light Spectrum of the Disk Around TW Hya: Detection of a Partially Filled Disk Gap at 80 AU
• Spiral arms in the disk of HD 142527 from CO emission lines with ALMA
• Systematic Variations of CO Gas Abundance with Radius in Gas-rich Protoplanetary Disks
• Discovery of a point-like source and a third spiral arm in the transition disk around the Herbig Ae star MWC 758
• Planet-driven spiral arms in protoplanetary disks: I. Formation mechanism
• Chasing Shadows: Rotation of the Azimuthal Asymmetry in the TW Hya Disk
• The Disk Substructures at High Angular Resolution Project (DSHARP): X. Multiple rings, a misaligned inner disk, and a bright arc in the disk around the T Tauri star HD 143006
• Water vapor distribution in protoplanetary disks
• A Gap with a Deficit of Large Grains in the protoplanetary disk around TW Hya
• On the origin of the spiral morphology in the Elias 2-27 circumstellar disc
• Dust-trapping vortices and a potentially planet-triggered spiral wake in the pre-transitional disk of V1247 Orionis
• Kinematic detections of protoplanets: a Doppler-flip in the disk of HD100546
• Flybys in protoplanetary discs: II. Observational signatures
• Observability of planet-disc interactions in CO kinematics
• Ring formation and dust dynamics in wind-driven protoplanetary discs: global simulations
• Mapping the Conditions for Hydrodynamic Instability on Steady State Accretion Models of Protoplanetary Disks
• Evidence For A Vertical Dependence on the Pressure Structure in AS 209
• Inferring giant planets from ALMA millimeter continuum and line observations in (transition) disks
• Planet-disk interaction in disks with cooling: basic theory
• Planet-driven spiral arms in protoplanetary disks: II. Implications
• Multiple spiral arms in the disk around intermediate-mass binary HD 34700A
• Long Baseline Observations of the HD100546 Protoplanetary Disk with ALMA
• Efficiency of thermal relaxation by radiative processes in protoplanetary discs: constraints on hydrodynamic turbulence
• Spiral Structure in the Gas Disk of TW Hya
• Gap, shadows, spirals, streamers: SPHERE observations of binary-disk interactions in GG Tau A
• Diverse protoplanetary disk morphology produced by a Jupiter-mass planet
• Spiral-driven accretion in protoplanetary discs - I. 2D models
• Blobs, spiral arms, and a possible planet around HD 169142
• Planetary Signatures in the SAO 206462 (HD 135344B) Disk: A Spiral Arm Passing Through Vortex?
• The effects of disk self-gravity and radiative cooling on the formation of gaps and spirals by young planets
• Is the spiral morphology of the Elias 2-27 circumstellar disc due to gravitational instability?
• Gaps and Rings in Protoplanetary Disks with Realistic Thermodynamics: The Critical Role of In-Plane Radiation Transport
• Planet-Disk interaction in 3D: the importance of buoyancy waves
• Large-scale CO spiral arms and complex kinematics associated with the T Tauri star RU Lup
• Spirals inside the millimeter cavity of transition disk SR 21
• Zombie Vortex Instability. III. Persistence with Nonuniform Stratification and Radiative Damping
• Low-mass planet migration in three dimensional wind-driven inviscid discs: a negative corotation torque
• Self-Destructing Spiral Waves: Global Simulations of a Spiral Wave Instability in Accretion Disks
• Subaru/HiCIAO $H{K}_{\mathrm{s}}$ imaging of LkH$\alpha$ 330 - multi-band detection of the gap and spiral-like structures
• The Spiral Wave Instability Induced by a Giant Planet: I. Particle Stirring in the Inner Regions of Protoplanetary Disks
• DZ Cha: a bona fide photoevaporating disc
• A Tight Relation between Spiral Arm Pitch Angle and Protoplanetary Disk Mass
• An Analytic Model for Buoyancy Resonances in Protoplanetary Disks

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• Nonlinear analysis of gravitational instability in a 3D gaseous disc
• Gas and Dust Shadows in the TW Hydrae Disk
• CO Line Emission Surfaces and Vertical Structure in Mid-Inclination Protoplanetary Disks