A multi-wavelength interferometric study of the massive young stellar object IRAS 13481-6124

• Published in: Astronomy and astrophysics (Berlin) Vol. 586; p. A78
• Main Authors: Boley, Paul A., Kraus, Stefan, de Wit, Willem-Jan, Linz, Hendrik, van Boekel, Roy, Henning, Thomas, Lacour, Sylvestre, Monnier, John D., Stecklum, Bringfried, Tuthill, Peter G.
• Format: Journal Article
• Language: English
• Published: EDP Sciences 01.02.2016
• Subjects: Astronomy; Astrophysics; Disks; Inclination; Infrared; Interferometry; Physics; Spectra; Spectral energy distribution; stars: individual: IRAS 13481-6124; stars: massive; techniques: interferometric; Wavelengths
• ISSN: 0004-6361; 1432-0746; 1432-0756
• DOI: 10.1051/0004-6361/201527502

We present new mid-infrared interferometric observations of the massive young stellar object IRAS 13481-6124, using VLTI/MIDI for spectrally-resolved, long-baseline measurements (projected baselines up to ~120 m) and GSO/T-ReCS for aperture-masking interferometry in five narrow-band filters (projected baselines of ~1.8−6.4 m) in the wavelength range of 7.5−13μm. We combine these measurements with previously-published interferometric observations in the K and N bands in order to assemble the largest collection of infrared interferometric observations for a massive YSO to date. Using a combination of geometric and radiative-transfer models, we confirm the detection at mid-infrared wavelengths of the disk previously inferred from near-infrared observations. We show that the outflow cavity is also detected at both near- and mid-infrared wavelengths, and in fact dominates the mid-infrared emission in terms of total flux. For the disk, we derive the inner radius (~1.8 mas or ~6.5 AU at 3.6 kpc), temperature at the inner rim (~1760 K), inclination (~48°) and position angle (~107°). We determine that the mass of the disk cannot be constrained without high-resolution observations in the (sub-)millimeter regime or observations of the disk kinematics, and could be anywhere from ~10-3 to 20M⊙. Finally, we discuss the prospects of interpreting the spectral energy distributions of deeply-embedded massive YSOs, and warn against attempting to infer disk properties from the spectral energy distribution.