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 ∼ 40 {km} {{{s}}}-1 and mass-loss rates ∼ {10}-9 {M}⊙ {{yr}}-1 when driven primarily by ionizing UV radiation. Observable molecules, including CO, {OH}, and {{{H}}}2{{O}} 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 thermochemistry. Divergent results concerning the efficiency of X-ray photoevaporation are traced in part to differing assumptions about dust and other coolants.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2017
- DOI:
- 10.3847/1538-4357/aa8726
- arXiv:
- arXiv:1706.03155
- Bibcode:
- 2017ApJ...847...11W
- Keywords:
-
- accretion;
- accretion disks;
- astrochemistry;
- circumstellar matter;
- methods: numerical;
- planetary systems;
- planets and satellites: formation;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- 15 pages, 9 figures, submitted to ApJ