Hydrodynamic Photoevaporation of Protoplanetary Disks with Consistent Thermochemistry

Abstract

Photoevaporation is an important dispersal mechanism for protoplanetary disks. We conduct hydrodynamic simulations coupled with ray-tracing radiative transfer and consistent thermochemistry to study photoevaporative winds driven by ultraviolet and X-ray radiation from the host star. Most models have a three-layer structure: a cold midplane, warm intermediate layer, and hot wind, the last having typical speeds $\sim 30{\mathrm{km}\mathrm{s}}^{-1}$ and mass-loss rates $\sim 10^{-9}{M}_{\odot }{\mathrm{yr}}^{-1}$ when driven primarily by ionizing UV radiation. Observable molecules including CO, OH and H2O re-form in the intermediate layer and survive at relatively high wind temperatures due to reactions being out of equilibrium. Mass-loss rates are sensitive to the intensity of radiation in energy bands that interact directly with hydrogen. Comparison with previous works shows that mass loss rates are also sensitive to the treatment of both the hydrodynamics and the thermochemistry. Divergent results concerning the efficiency of X-ray photoevaporation are traced in part to differing assumptions about dust and other coolants.

15 pages, 9 figures, submitted to ApJ

References in corpus (9)

• Photoevaporation of protoplanetary discs II: evolutionary models and observable properties
• Photoevaporation of protoplanetary discs I: hydrodynamic models
• Heat and Dust in Active Layers of Protostellar Disks
• X-ray irradiated protoplanetary disk atmospheres I: Predicted emission line spectrum and photoevaporation
• Line Emission from Gas in Optically Thick Dust Disks around Young Stars
• Tracing Slow Winds from T Tauri Stars via Low Velocity Forbidden Line Emission
• Spatially extended PAHs in circumstellar disks around T Tauri and Herbig Ae stars
• Shielding by Water and OH in FUV and X-ray Irradiated Protoplanetary Disks
• Photochemical-dynamical models of externally FUV irradiated protoplanetary discs

Cited by in corpus (9)

• Global Hydromagnetic Simulations of Protoplanetary Disks with Stellar Irradiation and Simplified Thermochemistry
• The first multi-dimensional view of mass loss from externally FUV irradiated protoplanetary discs
• A dusty origin for the correlation between protoplanetary disc accretion rates and dust masses
• Radiation pressure clear-out of dusty photoevaporating discs
• Radiation-Hydrodynamical Models of X-ray Photoevaporation in Carbon Depleted Circumstellar Discs
• Forbidden line diagnostics of photoevaporative disc winds
• Migrating Low-Mass Planets in Inviscid Dusty Protoplanetary Discs
• Chemical network reduction in protoplanetary disks
• Modelling thermochemical processes in protoplanetary disks I: numerical methods