Nonlinear evolution of streaming instabilities in accreting protoplanetary disks

Abstract

The streaming instability (SI) is one of the most promising candidates for triggering planetesimal formation by producing dense dust clumps that undergo gravitational collapse. Understanding how the SI operates in realistic protoplanetary disks (PPDs) is therefore crucial to assess the efficiency of planetesimal formation. Modern models of PPDs show that large-scale magnetic torques or winds can drive laminar gas accretion near the disk midplane. In a previous study, we identified a new linear dust-gas instability, the azimuthal drift SI (AdSI), applicable to such accreting disks and is powered by the relative azimuthal motion between dust and gas that results from the gas being torqued. In this work, we present the first nonlinear simulations of the AdSI. We show that it can destabilize an accreting, dusty disk even in the absence of a global radial pressure gradient, which is unlike the classic SI. We find the AdSI drives turbulence and the formation of vertically-extended dust filaments that undergo merging. In dust-rich disks, merged AdSI filaments reach maximum dust-to-gas ratios exceeding 100. Moreover, we find that even in dust-poor disks the AdSI can increase local dust densities by two orders of magnitude. We discuss the possible role of the AdSI in planetesimal formation, especially in regions of an accreting PPD with vanishing radial pressure gradients.

Accepted by ApJ

References in corpus (13)

• Particle Stirring in Turbulent Gas Disks: Including Orbital Oscillations
• How to form planetesimals from mm-sized chondrules and chondrule aggregates
• Initial mass function of planetesimals formed by the streaming instability
• Global Simulations of the Inner Regions of Protoplanetary Disks with Comprehensive Disk Microphysics
• Turbulence sets the length scale for planetesimal formation: Local 2D simulations of streaming instability and planetesimal formation
• Streaming Instability for Particle-Size Distributions
• A thermodynamic view of dusty protoplanetary disks
• On the Feeding Zone of Planetesimal Formation by the Streaming Instability
• Global Hydromagnetic Simulations of Protoplanetary Disks with Stellar Irradiation and Simplified Thermochemistry
• Ring formation and dust dynamics in wind-driven protoplanetary discs: global simulations
• Global Three-Dimensional Simulations of Outer Protoplanetary Disks with Ambipolar Diffusion
• Streaming Instability with Multiple Dust Species: II. Turbulence and Dust-Gas Dynamics at Nonlinear Saturation
• Stratified and vertically-shearing streaming instabilities in protoplanetary disks