Photoevaporation of protoplanetary disks by Far-UV photons arising from neighbouring massive stars: observation of proplyds and modelling

TL;DR

This paper investigates how far-UV photons from nearby massive stars cause photoevaporation of protoplanetary disks, combining observations and models to understand the physical processes and impact on disk evolution.

Contribution

It provides new observational data and modeling insights into far-UV driven photoevaporation of protoplanetary disks, a process not well constrained before.

Findings

Identification of key physical parameters like density and temperature.

Analysis of gas heating and cooling mechanisms involved.

Estimation of photoevaporation impact on disk evolution.

Abstract

Protoplanetary disks are found around young stars, and represent the embryonic stage of planetary systems. At different phases of their evolution, disks may undergo substantial mass-loss by photoevaporation: energetic photons from the central or a nearby star heat the disk, hence particles can escape the gravitational potential and the disk loses mass. However, this mechanism, and the underlying physics regulating photoevaporation, have not been well constrained by observations so far. The aims of this thesis are to study photoevaporation, in the specific case when it is driven by far-UV photons, to identify the main physical parameters (density, temperature) and processes (gas heating and cooling mechanisms) that are involved, and to estimate its impact on the disk dynamical evolution. The study relies on coupling observations and models of disks being photoevaporated by UV photons coming from neighbouring massive star(s).