Laboratoire Dynamique des Etoiles, des (Exo)-planètes, et de leur environnement

The origin of the heaviest elements is still a matter of debate. For the rapid neutron capture process (r-process), multiple sites have been proposed, e.g., neutron star mergers and (sub-classes) of supernovae (e.g., magnetorotationally driven supernovae). R-process elements have been measured in a large fraction of metal-poor stars. Galactic archaeology studies show that the r-process abundances among these stars vary by over 2 orders of magnitude. On the other hand, abundances in stars with solar-like metallicity do not differ greatly. This leads to two major open questions:
1. What is the reason for such a huge abundance scatter of r-process elements in the early galaxy?
2. While the large scatter at low metallicities might point to a rare production site, why is there barely any scatter at solar metallicities?
We use a high resolution three-dimensional Galactic chemical evolution model to simulate the abundances of r-process elements and short lived (<100 My) radioisotopes over the lifetime of the Galaxy, in order to better constrain the site of the r-process.

Organizer: Matteo BUGLI

Hybrid seminar: Galilée room & Zoom