From primordial composition of stars to the present-day composition of their rocky exoplanets

12 Nov 2024, 15:00
30m
Sala Capitolo (Fuligno Cenacle)

Sala Capitolo

Fuligno Cenacle

Via Faenza 48, 50123, Firenze

Speakers

Dr Barbara Soares Vardan Adibekyan (Instituto de Astrofísica e Ciências do Espaço (IA))

Description

Stellar atmospheres offer the only observational window into the remnants of planet-forming disk composition, given that disks, with lifetimes typically lasting only a few million years, have long dissipated around most discovered planet-hosting stars. When modeling the interiors of rocky planets an one-to-one relation between the composition of the planet and the host stars is typically assumed. However, Adibekyan et al (2021) showed that while there is a relation between the composition of rocky planets and their host stars, the relation is not one-to-one. The study by Adibekyan et al. (2021) has two potential limitations: i) The interiors of the planets were modeled assuming they are made only of core and mantle, i.e., no volatiles, and ii) the present-day stellar abundances were used as a proxy for the primordial protoplanetary disk composition. Some astrophysical
processes, such as atomic diffusion, can influence the stellar composition as the star
evolves. Thus, the present-day stellar abundances can be measurably different from their primordial composition.
Over the last two years, we worked on the EXO-Terra project, which aimed at a comprehensive analysis of the star-planet compositional link by overcoming the two aforementioned limitations.
Additionally, we increased the sample by about 50%. I propose an oral contribution to present the final results of the EXO-Terra project.

Primary author

Dr Barbara Soares

Co-author

Vardan Adibekyan (Instituto de Astrofísica e Ciências do Espaço (IA))

Presentation materials