Evidence for Misaligned Disks in the T Tauri Triple System: 10 um Super-Resolution with MMTAO and Markov Chains

TL;DR

This study uses high-resolution mid-infrared adaptive optics and Markov Chain Monte Carlo methods to resolve and analyze the circumstellar disks in the T Tauri triple system, revealing misaligned disks and dust features.

Contribution

It introduces a novel MCMC technique for astrometric and photometric separation of close system components in the mid-IR, providing new insights into disk orientations.

Findings

T Tau Sa has a nearly edge-on circumstellar disk.

T Tau Sb lacks a similarly oriented disk.

The silicate feature is dominated by Sa's absorption.

Abstract

Although T Tauri is one of the most studied young objects in astronomy, the nature of its circumstellar environment remains elusive due, in part, to the small angular separation of its three components (North-South and South a-b are separated by 0.68" and 0.12" respectively). Taking advantage of incredibly stable, high Strehl, PSFs obtained with Mid-IR adaptive optics at the 6.5 meter MMT, we are able to resolve the system on and off the 10um silicate dust feature (8.7um, 10.55um, and 11.86um; 10% bandwidth), and broad N. At these wavelengths, South a-b are separated by only ~0.3 lambda/D. This paper describes a robust Markov Chain Monte Carlo technique to separate all three components astrometrically and photometrically, for the first time, in the mid-IR. Our results show that the silicate feature previously observed in the unresolved T Tau South binary is dominated by T Tau Sa's absorption, while Sb does not appear to have a significant feature. This suggests that a large circumbinary disk around Sa-Sb is not likely the primary source of cool dust in our line-of-sight, and that T Tau Sa is enshrouded by a nearly edge-on circumstellar disk. Surprisingly, T Tau Sb does not appear to have a similarly oriented disk.