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- Lectures
- Institute of Astronomy and Astrophysics
- Location
R1412 of the Astronomy-Mathematics Building, National Taiwan University
- Speaker Name
Jonathan Marshall [ASIAA]
- State
Definitive
- Url
Stirring in the deep: revealing the secrets of planetary systems with dusty planetesimal belts
2024-08-19 12:00 - 12:40
| Abstract: | Planetesimals -- asteroids and comets -- are the building blocks of planets in protoplanetary discs and the source of dust and gas in debris discs. Along with planets they comprise the left-over material after star formation that constitutes a planetary system. Planetesimals are dynamically stirred, exciting their orbits and inducing collisional velocities large enough to trigger a collisional cascade. This produces fragments ranging in size down to sub-micron dust grains; large, millimetre-sized dust grains are weakly affected by non-gravitational forces and therefore trace the location of dust-producing planetesimals within a system. Planets further influence the dynamics of planetesimals (and dust), sculpting the orbits of debris belts to produce asymmetries or gaps. We can constrain the architecture of planetary systems, and infer the presence of unseen planetary companions, by high spatial resolution, multi-wavelength imaging of debris discs, detecting the emission from large dust grains at (sub)millimetre wavelengths. In this talk I will present a predominantly ALMA-based perspective of the observation and modelling of the architectures of cold debris belts and the limits on planetary companions that can be inferred from these data. I will discuss these findings in the context of the ongoing ALMA large program ARKS which is targeting the radial and vertical structure of 17 bright debris discs. Finally, I will highlight potential future avenues for detection and interpretation of debris disc systems including ongoing ALMA observations and near-future facilities such as AtLAST. |
