Mid-infrared observations of the transitional disks around DH Tau, DM Tau, and GM Aur

TL;DR

This study uses mid-infrared observations to spatially resolve and analyze the inner structures of transitional disks around three young stars, providing new constraints on disk hole sizes and insights into disk evolution and planet formation.

Contribution

The paper presents the first spatial resolution of the GM Aur disk in the mid-infrared and constrains the inner disk hole sizes of DH Tau and DM Tau, advancing understanding of transitional disk structures.

Findings

Resolved GM Aur's disk with a 20.5 AU inner hole.

Constrained inner hole sizes of DH Tau and DM Tau to less than 15.5 AU.

Measured mid-infrared fluxes for all three disks.

Abstract

Aims: We present mid-infrared observations and photometry of the transitional disks around the young stellar objects DH Tau, DM Tau, and GM Aur, obtained with VISIR/VLT in N band. Our aim is to resolve the inner region and the large-scale structures of these transitional disks, carrying potential signatures of intermediate or later stages of disk evolution and ongoing planet formation. Methods: We use the simultaneously observed standard-stars as PSF reference to constrain the radial flux profiles of our target objects. Subtracting the obtained standard-star profile from the corresponding science object profile yields the flux residuals produced by the star-disk system. A detection threshold takes into account the background standard deviation and also the seeing variations during the observations to evaluate the significance of these flux residuals. On the basis of a simple model for the dust re-emission, we derive constraints on the inner radius of the dust disk. Results: We spatially resolve the transitional disk around GM Aur and determine an inner-disk hole radius of 20.5(+1.0,-0.5) AU. The circumstellar disks around DH Tau and DM Tau are not spatially resolved but we are able to constrain the inner-disk hole radius to <15.5(+9.0,-2.0) AU and <15.5(+0.5,-0.5) AU, respectively. The performed photometry yields fluxes of 178+-31 mJy for DH Tau, 56+-6 mJy for DM Tau, and 229+-14 mJy for GM Aur.