Abstract

The bulk metallicity of a planet is determined by the composition of gas and dust in the protoplanetary disc from which it forms, and by the ratio of dust to gas accreted during formation. In the Gravitational Instability (GI) theory of planet formation, regions of the disc collapse into fragments. It is generally assumed that due to this large-scale fragmentation GI produces planets with the same dust to gas ratio as the disc—resulting in a metallicity that matches that of the host star. However, there are mechanisms that can enrich a planet forming via GI with dust or metal-rich gas, potentially challenging this assumption. By making use of global, 3D hydrodynamic simulations of a fragmenting protoplanetary disc, we plan to determine if these mechanisms are sufficient for GI-formed planets to have significantly superstellar metallicity.