Composition of super-Earths, super-Mercuries, and their host stars
Abstract
Because of their common origin, it was assumed that the composition of planet building blocks should, to a first order, correlate with stellar atmospheric composition, especially for refractory elements. In fact, information on the relative abundance of refractory and major rock-forming elements such as Fe, Mg, Si has been commonly used to improve interior estimates for terrestrial planets. Recently Adibekyan et al. (2021) presented evidence of a tight chemical link between rocky planets and their host stars. In this study we add six recently discovered exoplanets to the sample of Adibekyan et al and re-evaluate their findings in light of these new data. We confirm that i) iron-mass fraction of rocky exoplanets correlates (but not a 1:1 relationship) with the composition of their host stars, ii) on average the iron-mass fraction of planets is higher than that of the primordial iron-mass fraction of the protoplanetary disk, iii) super-Mercuries are formed in disks with high iron content. Based on these results we conclude that disk-chemistry and planet formation processes play an important role in the composition, formation, and evolution of super-Earths and super-Mercuries.
Keywords
Cite
@article{arxiv.2112.14512,
title = {Composition of super-Earths, super-Mercuries, and their host stars},
author = {V. Adibekyan and N. C. Santos and C. Dorn and S. G. Sousa and A. A. Hakobyan and B. Bitsch and Ch. Mordasini and S. C. C. Barros and E. Delgado Mena and O. D. S. Demangeon and J. P. Faria and P. Figueira and B. M. T. B. Soares and G. Israelian},
journal= {arXiv preprint arXiv:2112.14512},
year = {2021}
}
Comments
Peer-reviewed conference (Astronomy in the Crossroads of Interdisciplinary and Multidisciplinary Sciences) proceeding