On the Origin of Dust Structures in Protoplanetary Disks: Constraints from the Rossby Wave Instability

Abstract

High resolution sub-mm observations of protoplanetary disks with ALMA have revealed that dust rings are common in large, bright disks. The leading explanation for these structures is dust-trapping in a local gas pressure maximum, caused by an embedded planet or other dynamical process. Independent of origin, such dust traps should be stable for many orbits to collect significant dust. However, ring-like perturbations in gas disks are also known to trigger the Rossby Wave Instability (RWI). We investigate whether axisymmetric pressure bumps can simultaneously trap dust and remain stable to the RWI. The answer depends on the thermodynamic properties of pressure bumps. For isothermal bumps, dust traps are RWI-stable for widths from $\sim 1$ to several gas scale-heights. Adiabatic dust traps are stable over a smaller range of widths. For temperature bumps with no surface density component, however, all dust traps tend to be unstable. Smaller values of disk aspect ratio allow stable dust trapping at lower bump amplitudes and over a larger range of widths. We also report a new approximate criterion for RWI. Instability occurs when the radial oscillation frequency is $\lesssim 75$\% of the Keplerian frequency, which differs from the well-known Lovelace necessary (but not sufficient) criterion for instability. Our results can guide ALMA observations of molecular gas by constraining the resolution and sensitivity needed to identify the pressure bumps thought to be responsible for dust rings.

arXiv comment11 pages, 5 figures, accepted to ApJL

References in corpus (47)

• Streaming Instabilities in Protoplanetary 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
• Rossby Wave Instability of Keplerian Accretion Disks
• A Major Asymmetric Dust Trap in a Transition Disk
• Linear and nonlinear evolution of the vertical shear instability in accretion discs
• Ring shaped dust accumulation in transition disks
• Particle Clumping and Planetesimal Formation Depend Strongly on Metallicity
• Zonal Flows and Long-Lived Axisymmetric Pressure Bumps in Magnetorotational Turbulence
• The Disk Substructures at High Angular Resolution Project (DSHARP) VI: Dust trapping in thin-ringed protoplanetary disks
• Rossby Wave Instability of Thin Accretion Disks -- II. Detailed Linear Theory
• Evidence of fast pebble growth near condensation fronts in the HL Tau protoplanetary disk
• Sintering-induced Dust Ring Formation in Protoplanetary Disks: Application to the HL Tau Disk
• Rossby Wave Instability of Thin Accretion Disks - III. Nonlinear Simulations
• Planetesimal formation near the snowline: in or out?
• Planets opening dust gaps in gas disks
• On the Formation of Planetesimals via Secular Gravitational Instabilities with Turbulent Stirring
• Reviving Dead Zones in Accretion Disks by Rossby Vortices at their Boundaries
• Cooling Requirements for the Vertical Shear Instability in Protoplanetary Disks
• Standing on the shoulders of giants: Trojan Earths and vortex trapping in low mass self-gravitating protoplanetary disks of gas and solids
• Thresholds for Particle Clumping by the Streaming Instability
• Radiation Hydrodynamical Turbulence In Protoplanetary Disks: Numerical Models and Observational Constraints
• Embryos grown in the dead zone: Assembling the first protoplanetary cores in low mass self-gravitating circumstellar disks of gas and solids
• Rossby Wave Instability and three-dimensional vortices in accretion disks
• Vortices in the Co-orbital Region of an Embedded Protoplanet
• An Origin of Multiple Ring Structure and Hidden Planets in HL Tau: A Unified Picture by Secular Gravitational Instability
• Streaming Instability for Particle-Size Distributions
• Protoplanetary Disk Rings as Sites for Planetesimal Formation
• Gaps, rings, and non-axisymmetric structures in protoplanetary disks - Emission from large grains
• From Grains to Planetesimals: Les Houches Lecture
• Parametric Study of the Rossby Wave Instability in a Two-Dimensional Barotropic Disk
• Planetesimal formation via sweep-up growth at the inner edge of dead zones
• Spontaneous ring formation in wind-emitting accretion discs
• Rossby Wave Instability in three dimensional discs
• Slowly-growing gap-opening planets trigger weaker vortices
• Rings and gaps produced by variable magnetic disk winds and avalanche accretion streams: I. Axisymmetric resistive MHD simulations
• Super-Reflection in Fluid Discs: Corotation Amplifier, Corotation Resonance, Rossby Waves, and Overstable Modes
• Type III migration in a low viscosity disc
• Dust segregation in Hall-dominated turbulent protoplanetary disks
• Thermal Wave Instability as an Origin of Gap and Ring Structures in Protoplanetary Disks
• Rayleigh Adjustment of Narrow Barriers in Protoplanetary Discs
• Non-barotropic linear Rossby wave instability in three-dimensional disks
• The 3D dust and opacity distribution of protoplanets in multi-fluid global simulations
• Planetesimal formation around the snow line: I. Monte Carlo simulations of silicate dust pile-up in a turbulent disk
• Rossby Wave Instabilities of Protoplanetary Discs with Cooling
• Emergence of vortices at the edges of planet-driven gaps in protoplanetary discs
• The detection of dust gap-ring structure in the outer region of the CR Cha protoplanetary disk

Cited by in corpus (6)

• exoALMA. VI. Rotating under Pressure: Rotation curves, azimuthal velocity substructures, and pressure variations
• Dust-gas dynamics driven by the streaming instability with various pressure gradients
• Formation of Multiple Dynamical Classes in the Kuiper Belt via Disk Dissipation
• Global magnetohydrodynamic simulations of the inner regions of protoplanetary discs. I. Zero-net flux regime
• Stability of Dusty Rings in Protoplanetary Discs
• Rossby wave instability in weakly ionized protoplanetary disks. II. radial B-fields