Dust entrainment in photoevaporative winds: Synthetic observations of transition disks

TL;DR

This study models dust entrainment in photoevaporative winds of transition disks around young stars, predicting observable features in scattered light that could be detected with current telescopes like JWST.

Contribution

It provides synthetic observations of dust in XEUV-driven winds, highlighting potential observable signatures and dust mass-loss rates in transition disks.

Findings

Dust mass-loss rate is less than 0.2% of gas mass-loss rate.

Synthesized images show chimney-like structures in the outflows.

Detection of these features is possible with JWST and current instruments.

Abstract

X-ray- and extreme-ultraviolet- (XEUV-) driven photoevaporative winds acting on protoplanetary disks around young T-Tauri stars may strongly impact disk evolution, affecting both gas and dust distributions. We compute dust densities for the wind regions of XEUV-irradiated transition disks with gap sizes of 20 and 30 AU, and determine whether they can be observed at wavelengths $0.7 \lesssim \lambda_\mathrm{obs} [\mu\mathrm{m}] \lesssim 1.8$ in scattered and polarised light with current instrumentation. For an XEUV-driven outflow around a $M_* = 0.7 \mathrm{M}_\odot$ T-Tauri star with $L_X = 2 \cdot 10^{30} \mathrm{erg/s}$, we find dust mass-loss rates $\dot{M}_\mathrm{dust} \lesssim 2.0 \cdot 10^{-3} \dot{M}_\mathrm{gas}$, and if we invoke vertical settling, the outflow is quite collimated. The synthesised images exhibit a distinct chimney-like structure. The relative intensity of these chimneys is low, but under optimal conditions, their detection may still be feasible with current instrumentation such as JWST NIRCam and SPHERE IRDIS.