Chemical diversity in protoplanetary discs and its impact on the formation history of giant planets

Comparative studies of protoplanetary discs, exoplanetary systems, and the Solar System revealed the extreme diversity in the orbital architectures of giant planets. Their detection over a wide range of orbital radii, spanning from 0.01 to 100 au from the host star, suggests that giant planets can interact with multiple and diverse chemical environments in protoplanetary discs while they form and migrate to their final orbits. Specifically, migration allows giant planets to grow by accreting gas and solids characterised by different compositions and relative abundances of refractory and volatile elements. The interplay between accretion and migration shapes the composition of giant planets and of their atmospheres: as such, the composition of planetary atmospheres can be used as a proxy into the formation and migration histories of giant planets. An extensive body of work investigated how the abundance ratio of the elements C and O allows to probe the formation pathways of giant planets, though most studies focused on formation regions closer to the star than suggested by observations. To explore the implications of such wider formation regions, we coupled N-body simulations of forming and migrating giant planets with astrochemical models of protoplanetary discs. In parallel, we extended the set of chemical tracers to include one of the most volatile elements, N, and one of the most refractory ones, S to enhance the set of elemental ratios. In this talk we discuss the implications of different disc astrochemical scenarios for the final composition of giant planets, and show how the enhanced set of elemental ratios can be used to constrain both the extent of migration and the sources of the planetary metallicity in both chemical inheritance and reset scenarios of the host protoplanetary disc....