Collisional Cascade Caclulations for Irregular Satellite Swarms in Fomalhaut b

TL;DR

This paper presents detailed numerical simulations of the collisional evolution of irregular satellite swarms around planets in the Fomalhaut system, exploring their observability and implications for young star systems.

Contribution

It provides the first extensive numerical analysis of satellite swarm evolution around a range of planet masses in the Fomalhaut system, linking theoretical models to observational constraints.

Findings

Swarm cross-sectional areas match Fomalhaut b observations for certain planet masses.

Optically thick satellite swarms are predicted for young planets (1-10 Myr).

Observations can constrain the frequency of such satellite systems around young stars.

Abstract

We describe an extensive suite of numerical calculations for the collisional evolution of irregular satellite swarms around 1--300 M-earth planets orbiting at 120 AU in the Fomalhaut system. For 10--100 M-earth planets, swarms with initial masses of roughly 1% of the planet mass have cross-sectional areas comparable to the observed cross-sectional area of Fomalhaut b. Among 30--300 M-earth planets, our calculations yield optically thick swarms of satellites for ages of 1-10 Myr. Observations with HST and ground-based AO instruments can constrain the frequency of these systems around stars in the beta Pic moving group and possibly other nearby associations of young stars.