PF-10-0022

Entrapment of hyper-volatiles in interstellar and cometary CO2 and H2O ice analogs

Alexia Simon

Planets and planetesimals acquire their volatiles through ice and gas accretion into protoplanetary disks around young stars. The composition of planets will depend on the distributions of those volatiles (in icy grain mantles and gas) across the disk, which depend on the disk temperature profiles. If the ices are present as a mixture, entrapment of more volatile species in less volatile ice matrices will change the prediction of the solid composition into planetary bodies since entrapment allows hyper-volatiles to be present in a solid form closer to the star. More recently, we showed that in addition to water, entrapment in CO2 ice might be important for the distribution of volatiles in disks. I want to present how hyper-volatile entrapment depends on the ice matrix properties, as well as the maximum amount of hyper-volatiles that can be trapped in a given volume of H2O and CO2 ice. Involving a discussion about the implications for the compositions of planet-forming bodies in disks. This work is a laboratory work looking at a range of four hyper-volatiles: CO, N2, CH4, and Ar, each mixed with an ice matrix: H2O and CO2; for a range of experimental conditions: thicknesses, mixture concentration, deposition temperature, and binary/multi-components mixtures.