VLTI/MIDI atlas of disks around low- and intermediate-mass young stellar objects

TL;DR

This study provides a comprehensive mid-infrared interferometric atlas of 82 disks around young stars, revealing disk structures, dust properties, and potential companions, and supports future observations with the MATISSE instrument.

Contribution

It offers a large, homogeneous dataset of mid-infrared interferometric observations and analysis methods for disks around young stars, including new insights into disk morphology and dust mineralogy.

Findings

Disks around T Tauri stars are colder and more extended than those around Herbig Ae stars.

Inner disk regions show weaker silicate features, indicating more processed dust.

Evidence of potential companions or asymmetric structures in two systems.

Abstract

Context. Protoplanetary disks show large diversity regarding their morphology and dust composition. With mid-infrared interferometry the thermal emission of disks can be spatially resolved, and the distribution and properties of the dust within can be studied. Aims. Our aim is to perform a statistical analysis on a large sample of 82 disks around low- and intermediate-mass young stars, based on mid-infrared interferometric observations. We intend to study the distribution of disk sizes, variability, and the silicate dust mineralogy. Methods. Archival mid-infrared interferometric data from the MIDI instrument on the VLTI are homogeneously reduced and calibrated. Geometric disk models are used to fit the observations to get spatial information about the disks. An automatic spectral decomposition pipeline is applied to analyze the shape of the silicate feature. Results. We present the resulting data products in the form of an atlas, containing N band correlated and total spectra, visibilities, and differential phases. The majority of our data can be well fitted with a continuous disk model, except for a few objects, where a gapped model gives a better match. From the mid-infrared size--luminosity relation we find that disks around T Tauri stars are generally colder and more extended with respect to the stellar luminosity than disks around Herbig Ae stars. We find that in the innermost part of the disks ($r \lesssim 1$~au) the silicate feature is generally weaker than in the outer parts, suggesting that in the inner parts the dust is substantially more processed. We analyze stellar multiplicity and find that in two systems (AB Aur and HD 72106) data suggest a new companion or asymmetric inner disk structure. We make predictions for the observability of our objects with the upcoming MATISSE instrument, supporting the practical preparations of future MATISSE observations of T Tauri stars.