Focusing of non-linear eccentric waves in astrophysical discs – II. Excitation and damping of tightly wound waves - Université de Lyon Access content directly
Journal Articles Monthly Notices of the Royal Astronomical Society Year : 2022

Focusing of non-linear eccentric waves in astrophysical discs – II. Excitation and damping of tightly wound waves

Abstract

In this paper, I develop a non-linear theory of tightly wound (highly twisted) eccentric waves in astrophysical discs, based on the averaged Lagrangian method of Whitham. Viscous dissipation is included in the theory by use of a pseudo-Lagrangian. This work is an extension of the theory developed by Lee & Goodman to 3D discs, with the addition of viscosity. I confirm that linear tightly wound eccentric waves are overstable and are excited by the presence of a shear viscosity and show that this persists for weakly non-linear waves. I find the waves are damped by shear viscosity when the wave become sufficiently non-linear, a result previously found in particulate discs. Additionally, I compare the results of this model to recent simulations of eccentric waves propagating in the inner regions of black hole discs and show that an ingoing eccentric wave can be strongly damped near the marginally stable orbit, resulting in a nearly circular disc, with a strong azimuthal variation in the disc density.
Fichier principal
Vignette du fichier
stab3605.pdf (1.01 Mo) Télécharger le fichier
Origin Publisher files allowed on an open archive

Dates and versions

hal-03531330 , version 1 (29-03-2023)

Identifiers

Cite

Elliot M. Lynch. Focusing of non-linear eccentric waves in astrophysical discs – II. Excitation and damping of tightly wound waves. Monthly Notices of the Royal Astronomical Society, 2022, 510 (3), pp.3460-3478. ⟨10.1093/mnras/stab3605⟩. ⟨hal-03531330⟩
26 View
18 Download

Altmetric

Share

Gmail Mastodon Facebook X LinkedIn More