Proefschrift
Probing the inner regions: a multi-wavelength view of accretion and outflow in protoplanetary disks
The zoo of detected exoplanets reveals both the uniqueness of our own Solar System and the complexity of planetary system formation, sparking fundamental questions about how planetary systems form and evolve.
- Auteur
- A.A. Rota
- Datum
- 20 februari 2026
- Links
- Thesis in Leiden Repository
Characterizing these processes is essential for understanding the origins of our own Solar System. This thesis investigates planet formation from an observational point of view, focusing on the disks of gas and dust that surround young stars, known as protoplanetary disks.Using archival observations from the ALMA and VLA radio telescopes, we studied these disks across multiple wavelengths, focusing in particular on disk with large dust cavities, the so-called transition disks. We found that the compact emission close to stars in the cavity of most of these disks is dominated by free-free emission from ionized gas associated with jets and/or MHD winds. Moreover, we found a strong correlation between the ionized mass loss rate (as inferred form the free-free emission) and the accretion rate, suggesting that the outflow is strictly connected to the stellar accretion and that accretion in these disks is mainly driven by a jet and/or MHD wind.Consistent results are found in a larger sample of full protoplanetary disks (i.e., disks without large inner cavities).Among the studied transition disks, we found that the compact emission in AB Aur, one of the brightest transition disks in terms of compact free-free emission, reveals evidence for a precessing jet, possibly linked to the influenced of a companion object.Finally, we investigate the gas and dust structures in a sample of three transition disks around K and M stars. Contrary to expectation, no significant differences in the brightness temperature or in the gas-to-dust ratio are found between our disks and other transition disks around moreluminous stars. This suggests that parameters other than luminosity play a role in setting the gas temperature structure.