Induced Turbulence and the Density Structure of the Dust Layer in a Protoplanetary Disk

Abstract

We study the turbulence induced in the dust layer of a protoplanetary disk based on the energetics of dust accretion due to gas drag. We estimate turbulence strength from the energy supplied by dust accretion, using the radial drift velocity of the dust particles in a laminar disk. Our estimate of the turbulence strength agrees with previous analytical and numerical research on the turbulence induced by Kelvin-Helmholtz and/or streaming instabilities for particles whose stopping time is less than the Keplerian time. For such small particles, the strongest turbulence is expected to occur when the dust-to-gas ratio of the disk is ~C_eff^(1/2) (h_g / r) ~ 10^(-2), where C_eff ~ 0.2 represents the energy supply efficiency to turbulence and h_g / r ~ 5 x 10^(-2) is the aspect ratio of the gas disk. The maximum viscosity parameter is alpha_max ~ C_eff T_s (h_g / r)^2 ~ 10^(-4) T_s, where T_s (<1) is the non-dimensional stopping time of the dust particles. Modification in the dust-to-gas ratio from the standard value, 10^(-2), by any process, results in weaker turbulence and a thinner dust layer, and consequently may accelerate the growth process of the dust particles.

Accepted in ApJ (18 pages, 11 figures)

References in corpus (14)

• Particle Stirring in Turbulent Gas Disks: Including Orbital Oscillations
• Closed-form expressions for particle relative velocities induced by turbulence
• Dust settling in local simulations of turbulent protoplanetary disks
• Planet formation bursts at the borders of the dead zone in 2D numerical simulations of circumstellar disks
• Dust sedimentation and self-sustained Kelvin-Helmholtz turbulence in protoplanetary disk mid-planes. I. Radially symmetric simulations
• Survival of the mm-cm size grain population observed in protoplanetary disks
• High-resolution simulations of planetesimal formation in turbulent protoplanetary discs
• Global MHD simulations of stratified and turbulent protoplanetary discs. II. Dust settling
• Embryos grown in the dead zone: Assembling the first protoplanetary cores in low mass self-gravitating circumstellar disks of gas and solids
• Midplane sedimentation of large solid bodies in turbulent protoplanetary discs
• Vertical Shearing Instabilities in Radially Shearing Disks: The Dustiest Layers of the Protoplanetary Nebula
• Three-Dimensional Simulations of Kelvin-Helmholtz Instability in Settled Dust Layers in Protoplanetary Disks
• Forming Planetesimals by Gravitational Instability: I. The Role of the Richardson Number in Triggering the Kelvin-Helmholtz Instability
• Kinematics of solid particles in a turbulent protoplanetary disc

Cited by in corpus (16)

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• Streaming Instability in Turbulent Protoplanetary Disks
• 3D Lagrangian turbulent diffusion of dust grains in a protoplanetary disk: method and first applications
• Streaming instability in the quasi-global protoplanetary discs
• The Resonant Drag Instability (RDI): Acoustic Modes
• Collisional Growth and Fragmentation of Dust Aggregates with Low Mass Ratios. I: Critical Collision Velocity for Water Ice
• Minimum Dust Abundances for Planetesimal Formation via Secular Gravitational Instabilities
• Survival of ALMA Rings in the Absence of Pressure Maxima
• United Theory of Planet Formation (I): Tandem Regime
• Nonlinear Outcome of Coagulation Instability in Protoplanetary Disks II: Dust Ring Formation Mediated by Backreaction and Fragmentation
• On Secular Gravitational Instability in Vertically Stratified Disks
• The Possibility of the Kelvin-Helmholtz Instability during Sedimentation of Dust Grains in the Protoplanetary Disk
• Experimental evidence for granular shear-flow instability in the Epstein regime