PARTICLE TRAPPING AND STREAMING INSTABILITY IN VORTICES IN PROTOPLANETARY DISKS

Journal Article · Fri May 01 04:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/804/1/35· OSTI ID:22522476

Raettig, Natalie; Klahr, Hubert ^[1]; Lyra, Wladimir ^[2]

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1. Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany)
2. Division of Geological and Planetary Science, California Institute of Technology, 1200 E California Blvd MC 150-12, Pasadena, CA 91125 (United States)

We analyze the concentration of solid particles in vortices created and sustained by radial buoyancy in protoplanetary disks, e.g., baroclinic vortex growth. Besides the gas drag acting on particles, we also allow for back-reaction from dust onto the gas. This becomes important when the local dust-to-gas ratio approaches unity. In our two-dimensional, local, shearing sheet simulations, we see high concentrations of grains inside the vortices for a broad range of Stokes numbers, St. An initial dust-to-gas ratio of 1:100 can easily be reversed to 100:1 for St = 1.0. The increased dust-to-gas ratio triggers the streaming instability, thus counter-intuitively limiting the maximal achievable overdensities. We find that particle trapping inside vortices opens the possibility for gravity assisted planetesimal formation even for small particles (St = 0.01) and a low initial dust-to-gas ratio of 1:10{sup 4}, e.g., much smaller than in the previously studied magnetohydrodynamic zonal flow case.

• OSTI ID: 22522476
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 804; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCRETION DISKS
CONCENTRATION RATIO
COSMIC DUST
DRAG
GRAVITATION
HYDRODYNAMICS
INSTABILITY
MAGNETOHYDRODYNAMICS
PARTICLES
PROTOPLANETS
SHEAR
STOKES NUMBER
TRAPPING
TURBULENCE
TWO-DIMENSIONAL CALCULATIONS
VORTICES