Dust Resurgence in Protoplanetary Disks Due to Planetesimal–Planet Interactions
Lia Marta Bernabò, D. Turrini, L. Testi, F. Marzari, D. Polychroni
Abstract
Abstract Observational data on the dust content of circumstellar disks show that the median dust content in disks around pre-main-sequence stars in nearby star-forming regions seems to increase from ∼1 to ∼2 Myr and then decline with time. This behavior challenges the models where the small dust grains steadily decline by accumulating into larger bodies and drifting inwards on a short timescale (≤1 Myr). In this Letter we explore the possibility to reconcile this discrepancy in the framework of a model where the early formation of planets dynamically stirs the nearby planetesimals and causes high-energy impacts between them, resulting in the production of second-generation dust. We show that the observed dust evolution can be naturally explained by this process within a suite of representative disk-planet architectures.