Super-Earths Composition and the Connection to their Formation
Diana Valencia
University of Toronto at Scarborough


With the growing number of measured radii and masses for low-mass planets, we can determine their composition and investigate any trends in the data. For planets that fall under the rocky region, with mass and radius and a sophisticated internal structure model, we estimated the amount of core mass fraction and thus, iron to magnesium ratios for these planets. By comparing the chemical distribution of these planets to those of stars we find a wider spread in the chemistry of planets, thus suggesting a non-primordial origin. We investigated if this spread in composition could be explained by the reprocessing that happens during collisions in the giant impact phase during formation. We use an N-body code with more realistic collisions outcomes, that include debris production taken from parameterized smooth-particle hydrodynamic codes used to investigate collisions. We find that forming both iron-rich super-Earths like Kepler-100b, and super-Moons is problematic, pointing to issues with our current understanding of planet formation.

Date: Jeudi, le 23 avril 2020
Heure: 11:30
Lieu: Pour tous
  A-3561 - Campus MIL