Oral Presentation

Dust Properties of the HD 163296 Disk from High-Resolution Multi-Wavelength Observations Including ALMA Band 9 (0.45 mm)

Author(s): Kiyoaki Doi (MPIA)

Presenter: Kiyoaki Doi (Max Planck Institute for Astronomy)

Observational characterization of dust properties in planet-forming disks is essential for understanding the evolution from dust to planets. SED fitting is a powerful method, but it often suffers from degeneracies. High-frequency observations, such as ALMA Band 9, serve as a crucial temperature tracer to break these degeneracies. We present new high-resolution Band 9 observations of HD 163296, one of the brightest Class II disks with clear substructures. The observations successfully recover the previously identified central disk, two distinct rings, and extended outer emission. We performed SED fitting using high-resolution (0.06”) ALMA Band 3, 4, 6, 7, and 9 data covering 0.45 to 3.0 mm and constrained the dust size, surface density, and temperature without imposing a temperature profile. The inner ring temperature is consistent with a passive-disk model, whereas the outer ring is locally colder, consistent with being shadowed by the inner ring. The central disk and two rings contain sufficient dust mass to form cores of giant planets, and even the extended outer emission contains more than an Earth mass of dust. These results demonstrate the importance of high-resolution multi-wavelength observations, including high-frequency data.