Formation of Gaps in Self-gravitating Debris Disks by Secular Resonance in a Single-planet System. II. Towards a Self-consistent Model [EPA]

http://arxiv.org/abs/2305.00951


High-resolution observations of several debris disks reveal structures such as gaps and spirals, suggestive of gravitational perturbations induced by underlying planets. Most existing studies of planet–debris disk interactions ignore the gravity of the disk, treating it as a reservoir of massless planetesimals. In this paper, we continue our investigation into the long-term interaction between a single eccentric planet and an external, massive debris disk. Building upon our previous work, here we consider not only the axisymmetric component of the disk’s gravitational potential, but also the non-axisymmetric torque that the disk exerts on the planet (ignoring for now only the non-axisymmetric component of the disk \textit{self}-gravity). To this goal, we develop and test a semi-analytic `$N$-ring’ framework that is based on a generalized (softened) version of the classical Laplace–Lagrange secular theory. Using this tool, we demonstrate that even when the disk is less massive than the planet, not only can a secular resonance be established within the disk that leads to the formation of a wide non-axisymmetric gap (akin to those observed in HD 107146, HD 92945, and HD 206893), but that the very same resonance also damps the planetary eccentricity via a process known as resonant friction. We also develop analytic understanding of these findings, finding good quantitative agreement with the outcomes of the $N$-ring calculations. Our results may be used to infer both the dynamical masses of gapped debris disks and the dynamical history of the planets interior to them, as we exemplify for HD 206893.

Read this paper on arXiv…

A. Sefilian, R. Rafikov and M. Wyatt
Tue, 2 May 23
11/57

Comments: Submitted to AAS Journals: 33 Pages (including 7 pages of Appendices), 15 Figures, 1 Table, 3 Animations (see Ancillary files). Comments are welcome