# Improved Constraints on the Disk Around MWC 349A from the 23-Meter LBTI

## TL;DR

This paper presents high-resolution infrared interferometric observations of MWC 349A using the LBTI, refining constraints on its circumstellar disk and informing its evolutionary status.

## Contribution

The study provides improved spatial resolution data of MWC 349A's disk, ruling out large inner clearings and supporting the presence of skew and a compact infrared excess.

## Key findings

- Supports presence of skew in the disk
- Rules out inner clearings >14 mas
- Provides tighter constraints on disk parameters

## Abstract

We present new spatially resolved observations of MWC 349A from the Large Binocular Telescope Interferometer (LBTI), a 23-meter baseline interferometer made up of two, co-mounted 8-meter telescopes. MWC 349A is a B[e] star with an unknown evolutionary state. Proposed scenarios range from a young stellar object (YSO), to a B[e] supergiant, to a tight binary system. Radio continuum and recombination line observations of this source revealed a sub-arcsecond bipolar outflow surrounding a ~100 mas circumstellar disk. Followup infrared studies detected the disk, and suggested that it may have skew and an inner clearing. Our new infrared interferometric observations, which have more than twice the resolution of previously-published datasets, support the presence of both skew and a compact infrared excess. They rule out inner clearings with radii greater than ~14 mas. We show the improvements in disk parameter constraints provided by LBTI, and discuss the inferred disk parameters in the context of the posited evolutionary states for MWC 349A.