PROTOPLANETARY MIGRATION IN TURBULENT ISOTHERMAL DISKS

Journal Article · Mon Feb 01 04:00:00 EST 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/709/2/759· OSTI ID:21392300

Baruteau, C; Lin, D N. C., ^[1]

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1. Astronomy and Astrophysics Department, University of California, Santa Cruz, CA 95064 (United States)

In order to reproduce the statistical properties of the observed exoplanets, population synthesis models have shown that the migration of protoplanets should be significantly slowed down, and that processes stalling migration should be at work. Much current theoretical efforts have thus been dedicated to find physical effects that slow down, halt or even reverse migration. Many of these studies rely on the horseshoe drag, whose long-term evolution (saturated or not) is intimately related to the disk viscosity in laminar disk models. We investigate how the horseshoe drag exerted on a low-mass planet is altered by a more realistic treatment of the turbulence in protoplanetary disks. Two-dimensional hydrodynamic simulations are performed with a turbulence model that reproduces the main turbulence properties of three-dimensional magnetohydrodynamic calculations. We find that the horseshoe drag can remain unsaturated on the long term, depending on the turbulence strength. We show that the desaturation of the horseshoe drag by turbulence can be modeled by vortensity diffusion across the time-averaged planet's horseshoe region. At low-turbulence, the running-time-averaged torque is in good agreement with the total torque obtained for an equivalent laminar model, with a similar vortensity diffusion coefficient. At high turbulence, differences arise due to the time evolution of the averaged density profile with turbulence.

• OSTI ID: 21392300
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 709; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCRETION DISKS
DRAG
FLUID MECHANICS
HYDRODYNAMICS
MECHANICS
PLANETS
PROTOPLANETS
THREE-DIMENSIONAL CALCULATIONS
TORQUE
TURBULENCE
TWO-DIMENSIONAL CALCULATIONS