Speaker
Description
Oxygen is a reactive element that bonds not only to C and H, but also to a variety of other relatively abundant elements like Si, Mg and Fe. How much of this element we miss when we fail to account for species other than H2O and CO has yet to be fully determined within the framework of disequilibrium chemistry. The fate of oxygen is determined by the delicate balance between competing chemical, dynamical and condensation timescales. Wherever this sequestration is efficient, the impact on the retrieved C/O ratio can be substantial, since up to 30% of the O stock in a Solar-composition atmosphere can be locked away in undetected species. In this contribution we utilize a new chemical kinetics network to study how oxygen partitions among its main volatile and refractory carriers (including key Si, Mg and Fe oxides and hydroxides), for a grid of planets with different equilibrium temperatures, metallicities and vertical mixing strengths, while testing different hypotheses concerning the behavior of both iron and rock-forming condensates.