Gap opening by extremely low-mass planets in a viscous disk

Paul C. Duffell, Andrew I. MacFadyen

    Research output: Contribution to journalArticle

    Abstract

    By numerically integrating the compressible Navier-Stokes equations in two dimensions, we calculate the criterion for gap formation by a very low mass (q ∼ 10-4) protoplanet on a fixed orbit in a thin viscous disk. In contrast with some previously proposed gap-opening criteria, we find that a planet can open a gap even if the Hill radius is smaller than the disk scale height. Moreover, in the low-viscosity limit, we find no minimum mass necessary to open a gap for a planet held on a fixed orbit. In particular, a Neptune-mass planet will open a gap in a minimum mass solar nebula with suitably low viscosity (α ≲ 10-4). We find that the mass threshold scales as the square root of viscosity in the low mass regime. This is because the gap width for critical planet masses in this regime is a fixed multiple of the scale height, not of the Hill radius of the planet.

    Original languageEnglish (US)
    Article number41
    JournalAstrophysical Journal
    Volume769
    Issue number1
    DOIs
    StatePublished - May 20 2013

    Fingerprint

    planets
    planet
    viscosity
    scale height
    orbits
    solar nebula
    Neptune (planet)
    radii
    protoplanets
    Neptune
    Navier-Stokes equations
    Navier-Stokes equation
    thresholds

    Keywords

    • hydrodynamics
    • methods: numerical
    • planetdisk interactions
    • planets and satellites: formation
    • protoplanetary disks

    ASJC Scopus subject areas

    • Space and Planetary Science
    • Astronomy and Astrophysics

    Cite this

    Gap opening by extremely low-mass planets in a viscous disk. / Duffell, Paul C.; MacFadyen, Andrew I.

    In: Astrophysical Journal, Vol. 769, No. 1, 41, 20.05.2013.

    Research output: Contribution to journalArticle

    Duffell, Paul C. ; MacFadyen, Andrew I. / Gap opening by extremely low-mass planets in a viscous disk. In: Astrophysical Journal. 2013 ; Vol. 769, No. 1.
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