English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In protoplanetary disks, the inner boundary between an MRI active and inactive region has  recently been suggested to be a promising site for planet formation. A set of numerical  simulations has indeed shown that vortex formation mediated by the Rossby wave instability  is a natural consequence of the disk dynamics at that location. However, such models have  so far considered only the case of an isothermal equation of state, while the more complex  thermodynamics of this region may have strong consequences on disk properties because of  thermal ionization. Gas is heated by turbulent dissipation and radiatively cools on long  timescales because disks are optically thick.  Using a mean field model of the dynamics of  that boundary, Latter and Balbus (2012) have shown that this complexity can lead to  situations in which the active/dead interface moves systematically inward or outward,  depending on the initial conditions. This is because turbulent activity is controlled by  ohmic resistivity that is itself a sensitive function of temperature. Such a behavior  suggests, as observed in young stellar object, a nonsteady accretion onto the central  star.  Using the Godunov code Ramses, we have performed 3D global numerical simulations of  protoplanetary disks that relax the isothermal hypothesis in order to check the above  scenario. We confirm the existence of such MRI fronts, thus validating the mean field  approach described above. As shown by Latter and Balbus (2012), MRI fronts tend to stop at  a critical radius. We argue that the typical front velocity crucially depends on turbulent  diffusion of temperature. The diffusivity of temperature due to turbulence is measured to  be order of H2/Ω where  Ω is the local orbital time and H the typical height  of the disk

Dynamics of the inner edge of the dead zone in protoplanetaty disks