Photoevaporative Dispersal of Protoplanetary Disks around Evolving Intermediate-mass Stars

TL;DR

This paper investigates how stellar evolution impacts the dispersal of protoplanetary disks around intermediate-mass stars by modeling the effects of photoevaporation driven by stellar radiation over time.

Contribution

It introduces a numerical model that incorporates stellar evolution and variable photoevaporation rates to study disk dispersal around intermediate-mass stars.

Findings

Stellar radiation luminosities evolve significantly within a few million years.

Photoevaporation rates change by orders of magnitude over the stellar lifetime.

Stellar evolution is essential for understanding disk dispersal around intermediate-mass stars.

Abstract

We aim to understand the effect of stellar evolution on the evolution of protoplanetary disks. We focus in particular on the disk evolution around intermediate-mass (IM) stars, which evolve more rapidly than low-mass ones. We numerically solve the long-term evolution of disks around 0.5-5 solar-mass stars considering viscous accretion and photoevaporation (PE) driven by stellar far-ultraviolet (FUV), extreme-ultraviolet (EUV), and X-ray emission. We also take stellar evolution into account and consider the time evolution of the PE rate. We find that the FUV, EUV, and X-ray luminosities of IM stars evolve by orders of magnitude within a few Myr along with the time evolution of stellar structure, stellar effective temperature, or accretion rate. Therefore, the PE rate also evolves with time by orders of magnitude, and we conclude that stellar evolution is crucial for the disk evolution around IM stars.