Azimuthal patterns in planetesimal circumstellar disks

TL;DR

This paper investigates how azimuthal resonant patterns form in circumstellar planetesimal disks with planets, showing that particles can concentrate into observable patterns rapidly through resonance effects.

Contribution

The study combines analytical estimates and numerical experiments to demonstrate the formation of azimuthal patterns in disks due to mean-motion resonances, highlighting their observability.

Findings

Resonant particles concentrate into azimuthal patterns within ~100 orbital periods.

The prominence of patterns depends on the planet-to-star mass ratio, μ.

Patterns associated with 2:1 and 3:2 resonances are most clearly observable.

Abstract

Ways of formation of azimuthal resonant patterns in circumstellar planetesimal disks with planets are considered. Our analytical estimates and massive numerical experiments show that the disk particles that initially reside in zones of low-order mean-motion resonances with the planet may eventually concentrate into potentially observable azimuthal patterns. The structuring process is rapid, usually taking ~100 orbital periods of the planet. It is found that the relative number of particles that retain their resonant position increases with decreasing the mass parameter $\mu$ (the ratio of masses of the perturbing planet and the parent star), but a significant fraction of the particle population is always removed from the disk due to accretion of the particles onto the star and planet, as well as due to their transition to highly elongated and hyperbolic orbits. Expected radio images of azimuthally structured disks are constructed. In the considered models, azimuthal patterns associated with the 2:1 and 3:2 resonances are most clearly manifested; observational manifestations of the 1:2 and 2:3 resonances are also possible.