Rayleigh adjustment of narrow barriers in protoplanetary discs
Author
Summary, in English
Sharp density features in protoplanetary discs, for instance at the edge of a magnetically dead zone, have recently been proposed as effective barriers to slow down or even stop the problematically fast migration of planetary cores into their central star. Density features on a radial scale approaching the disc vertical scaleheight might not exist, however, since they could be Rayleigh (or more generally Solberg-Høiland) unstable. Stability must be checked explicitly in one-dimensional viscous accretion disc models because these instabilities are artificially eliminated in the process of reducing the full set of axisymmetric equations. The disc thermodynamics, via the entropy stratification, and its vertical structure also influence stability when sharp density features are present. We propose the concept of Rayleigh adjustment for viscous disc models: any density feature that violates Rayleigh stability (or its generalization) should be diffused radially by hydrodynamical turbulence on a dynamical time-scale, approaching marginal stability in a quasi-continuous manner.
Publishing year
2010
Language
English
Pages
2436-2440
Publication/Series
Monthly Notices of the Royal Astronomical Society
Volume
402
Issue
4
Links
Document type
Journal article
Publisher
Oxford University Press
Topic
- Astronomy, Astrophysics and Cosmology
Keywords
- accretion accretion discs hydrodynamics instabilities planetary systems: formation planetary systems: protoplanetary discs
Status
Published
ISBN/ISSN/Other
- ISSN: 1365-2966