The interplay between forming planets and photo-evaporating discs I: Forbidden line diagnostics

Abstract

Disc winds and planet formation are considered to be two of the most important mechanisms that drive the evolution and dispersal of protoplanetary discs and in turn define the environment in which planets form and evolve. While both have been studied extensively in the past, we combine them into one model by performing three-dimensional radiation-hydrodynamic simulations of giant planet hosting discs that are undergoing X-ray photo-evaporation, with the goal to analyse the interactions between both mechanisms. In order to study the effect on observational diagnostics, we produce synthetic observations of commonly used wind-tracing forbidden emission lines with detailed radiative transfer and photo-ionisation calculations. We find that a sufficiently massive giant planet carves a gap in the gas disc that is deep enough to affect the structure and kinematics of the pressure-driven photo-evaporative wind significantly. This effect can be strong enough to be visible in the synthetic high-resolution observations of some of our wind diagnostic lines, such as the [OI] 6300 Å or [SII] 6730 Å lines. When the disc is observed at inclinations around 40° and higher, the spectral line profiles may exhibit a peak in the redshifted part of the spectrum, which cannot easily be explained by simple wind models alone. Moreover, massive planets can induce asymmetric substructures within the disc and the photo-evaporative wind, giving rise to temporal variations of the line profiles that can be strong enough to be observable on timescales of less than a quarter of the planet's orbital period.

Accepted for publication in MNRAS. 13+3 pages, 8+1 figures

References in corpus (16)

• PLUTO: a Numerical Code for Computational Astrophysics
• A comparative study of disc-planet interaction
• Global simulations of protoplanetary disks with ohmic resistivity and ambipolar diffusion
• CHIANTI - an atomic database for emission lines - Paper XV: Version 9, improvements for the X-ray satellite lines
• Hall-effect Controlled Gas Dynamics in Protoplanetary Disks: II. Full 3D Simulations toward the Outer Disk
• X-ray irradiated protoplanetary disk atmospheres I: Predicted emission line spectrum and photoevaporation
• Global Simulations of the Inner Regions of Protoplanetary Disks with Comprehensive Disk Microphysics
• Tracing Slow Winds from T Tauri Stars via Low Velocity Forbidden Line Emission
• X-ray enabled MOCASSIN: a 3D code for photoionized media
• Global Hydromagnetic Simulations of Protoplanetary Disks with Stellar Irradiation and Simplified Thermochemistry
• [NeII] emission line profiles from photoevaporative disc winds
• The link between disc dispersal by photoevaporation and the semi-major axis distribution of exoplanets
• The dispersal of protoplanetary discs. II: Photoevaporation models with observationally derived irradiating spectra
• The interpretation of protoplanetary disc wind diagnostic lines from X-ray photoevaporation and analytical MHD models
• Forbidden line diagnostics of photoevaporative disc winds
• The imprint of X-ray photoevaporation of planet-forming discs on the orbital distribution of giant planets

Cited by in corpus (4)

• [OI] 6300Å emission as a probe of external photoevaporation of protoplanetary discs
• A localized kinematic structure detected in atomic carbon emission spatially coincident with a proposed protoplanet in the HD 163296 disk
• High-resolution [OI] line spectral mapping of TW Hya consistent with X-ray driven photoevaporation
• The interplay between forming planets and photoevaporating discs II: Wind-driven gas redistribution