2006/11/11 by Raquel Salmeron, Arieh Königl, Arieh Konigl +2 · 3 citations
Chemistry · Physics and Astronomy · #Advanced Chemical Physics Studies #Astrophysics and Star Formation Studies #Molecular Spectroscopy and Structure #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2006.11277.x
published as Mon.Not.Roy.Astron.Soc.375:177-183,2007 · 8 pages, 4 figures, 1 table; accepted for publication in MNRAS
arxiv created 2006/11/11 · openalex publication_date 2007/01/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
Angular momentum transport in protostellar discs can take place either radially, through turbulence induced by the magnetorotational instability (MRI), or vertically, through the torque exerted by a large-scale magnetic field that threads the disc. Using semi-analytic and numerical results, we construct a model of steady-state discs that includes vertical transport by a centrifugally driven wind as well as MRI-induced turbulence. We present approximate criteria for the occurrence of either one of these mechanisms in an ambipolar diffusion-dominated disc. We derive ‘strong field’ solutions in which the angular momentum transport is purely vertical and ‘weak field’ solutions that are the stratified-disc analogues of the previously studied MRI channel modes; the latter are transformed into accretion solutions with predominantly radial angular momentum transport when we implement a turbulent-stress prescription based on published results of numerical simulations. We also analyse ‘intermediate field strength’ solutions in which both modes of transport operate at the same radial location; we conclude, however, that significant spatial overlap of these two mechanisms is unlikely to occur in practice. To further advance this study, we have developed a general scheme that incorporates also the Hall and Ohm conductivity regimes in discs with a realistic ionization structure.