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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Warped accretion discs are expected in many protostellar binary systems. Inthis paper, we study the long-term evolution of disc warp and precession fordiscs with dimensionless thickness $H/r$ larger than their viscosity parameter$\alpha$, such that bending waves can propagate and dominate the warpevolution. For small warps, these discs undergo approximately rigid-bodyprecession. We derive analytical expressions for the warp/twist profiles of thedisc and the alignment timescale for a variety of models. Applying our resultsto circumbinary discs, we find that these discs align with the orbital plane ofthe binary on a timescale comparable to the global precession time of the disc,and typically much smaller than its viscous timescale. We discuss theimplications of our finding for the observations of misaligned circumbinarydiscs (such as KH 15D) and circumbinary planetary systems (such as Kepler-413);these observed misalignments provide useful constraints on the uncertainaspects of the disc warp theory. On the other hand, we find that circumstellardiscs can maintain large misalignments with respect to the plane of the binarycompanion over their entire lifetime. We estimate that inclination angleslarger than $\sim 20^\circ$ can be maintained for typical disc parameters.Overall, our results suggest that while highly misaligned circumstellar discsin binaries are expected to be common, such misalignments should be rare forcircumbinary discs. These expectations are consistent with current observationsof protoplanetary discs and exoplanets in binaries, and can be tested withfuture observations.

Evolution of linear warps in accretion discs and applications to protoplanetary discs in binaries