How consumption and repulsion set planetary gap depths and the final masses of gas giants

M. M. Rosenthal, E. I. Chiang, S. Ginzburg, R. A. Murray-Clay

Research output: Contribution to journalArticlepeer-review

22 Scopus citations

Abstract

Planets open gaps in discs. Gap opening is typically modelled by considering the planetary Lindblad torque which repels disc gas away from the planet's orbit. But gaps also clear because the planet consumes local material. We present a simple, easy-to-use, analytic framework for calculating how gaps deplete and how the disc's structure as a whole changes by the combined action of Lindblad repulsion and planetary consumption. The final mass to which a gap-embedded gas giant grows is derived in tandem. The analytics are tested against 1D numerical experiments and calibrated using published multidimensional simulations. In viscous alpha discs, the planet, while clearing a gap, initially accretes practically all of the gas that tries to diffuse past, rapidly achieving super-Jupiter if not brown dwarf status. By contrast, in inviscid discs-that may still accrete on to their central stars by, say, magnetized winds-planets open deep, repulsion-dominated gaps. Then only a small fraction of the disc accretion flow is diverted on to the planet, which grows to a fraction of a Jupiter mass. Transitional disc cavities might be cleared by families of such low-mass objects opening inviscid, repulsion-dominated, overlapping gaps which allow most of the outer disc gas to flow unimpeded on to host stars.

Original languageAmerican English
Pages (from-to)2054-2067
Number of pages14
JournalMonthly Notices of the Royal Astronomical Society
Volume498
Issue number2
DOIs
StatePublished - 1 Oct 2020
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.

Keywords

  • accretion, accretion discs
  • planet-disc interactions
  • planets and satellites: Formation
  • planets and satellites: Physical evolution
  • protoplanetary discs

Fingerprint

Dive into the research topics of 'How consumption and repulsion set planetary gap depths and the final masses of gas giants'. Together they form a unique fingerprint.

Cite this