Detection of Strong Millimeter Emission from the Circumstellar Dust Disk Around V1094 Sco: Cold and Massive Disk around a T Tauri Star in a Quiescent Accretion Phase?

TL;DR

This paper reports the discovery of a cold, massive circumstellar dust disk around the T Tauri star V1094 Sco, characterized by millimeter emission and molecular gas observations indicating a substantial, non-outflowing disk with a mass significantly larger than typical T Tauri disks.

Contribution

First detection of a cold, massive dust disk around V1094 Sco using 1.1 mm continuum and CO line observations, revealing a large, massive, and inner-hole-free disk in a quiescent accretion phase.

Findings

Disk mass estimated between 0.03 and 0.12 solar masses.

No evidence of large-scale outflows or envelopes.

Disk shows no inner hole, consistent with a flattened structure.

Abstract

We present the discovery of a cold massive dust disk around the T Tauri star V1094 Sco in the Lupus molecular cloud from the 1.1 millimeter continuum observations with AzTEC on ASTE. A compact ($r\lesssim$320 AU) continuum emission coincides with the stellar position having a flux density of 272 mJy which is largest among T Tauri stars in Lupus. We also present the detection of molecular gas associated with the star in the five-point observations in $^{12}$CO J=3--2 and $^{13}$CO J=3--2. Since our $^{12}$CO and $^{13}$CO observations did not show any signature of a large-scale outflow or a massive envelope, the compact dust emission is likely to come from a disk around the star. The observed SED of V1094 Sco shows no distinct turnover from near infrared to millimeter wavelengths, which can be well described by a flattened disk for the dust component, and no clear dip feature around 10 $\micron$ suggestive of absence of an inner hole in the disk. We fit a simple power-law disk model to the observed SED. The estimated disk mass ranges from 0.03 to $\gtrsim$0.12 $M_\sun$, which is one or two orders of magnitude larger than the median disk mass of T Tauri stars in Taurus.