Thesis title
Late accretion of gas from debris discs.
Composition of the jury
- Sandrine Vinatier (Research Director, LIRA) : Chairperson
- Jean-Charles Augereau (Astronomer, IPAG) : Rapporteur
- Clément Baruteau (Research Fellow, IRAP) : Rapporteur
- Sean Raymond (Research Director, LAB) : Examiner
- Héloïse Méheut (Senior Research Fellow, Lagrange) : Examiner
- Benoit Tabone (Research Fellow, IAS) : Examiner
- Tristant Guillot (Senior Research Fellow, Lagrange) : Examiner
- Quentin Kral (Assistant Astronomer, LIRA) : Thesis supervisor
Abstract
The relatively recent discovery of so-called “late” gas disks, which sometimes persist for several tens of millions of years after the protoplanetary disk has dissipated, is revolutionizing our understanding of the evolution of young stellar systems. However, the accretion of this gas onto planets remains a poorly studied phenomenon, even though initial estimates suggest that accretion is extremely efficient.
The work conducted in this thesis aimed to better describe this accretion, both in the Solar System and in extrasolar systems. To this end, two numerical models, one for the gas disk (Diffenix) and one for the atmospheres, were developed.
In particular, the study within the solar system focuses on the existence of a secondary CO gas disk that led to the enrichment of Uranus’s and Neptune’s atmospheres with carbon. The work by Kral et al. (2024), which proposes a new explanation for the origin of water on Earth through the accretion of gas from a secondary water vapor disk in the asteroid belt, has been extended to extrasolar systems, with the aim, in particular, of preparing for future observations.
