Processing of warm ices by low energy ions: probing the effects of solar wind and low energy magnetospheric ions on frozen Solar System bodies

Abstract

This project is a natural extension of the master project of Marina Gomes Rachid (FAPESP#2016/11334-5) on the effects of swift ions (15.7 MeV O+5) on astrophysical ices containing themixtures H2O:CO2:CH4 (10:1:1) and H2O:CO2:CH4:NH3 (10:1:1:1) at temperatures around 80 Kmonitored by infrared spectroscopy obtained at GANIL ion accelerator at France. Here, the mainobjective is to investigate the effects of low energy ions (solar wind and low energy magnetosphericparticles) on such ices. Therefore, the focus now will be the implantation processes and chemicalchanges in the energy domain ruled by the nuclear stopping power, in contrast with the Marina'sdissertation project, which involves ion-ice interactions in the electronic stopping-power regime(faster). The ice composition selected for the study have been observed in several surfaces of solarsystem frozen bodies (moons of Jupiter and Saturn, Pluto and other Kuiper belts, and comets). Wewill investigate the stability and chemical changes of these molecular species in space environmentsby determining the molecular effective dissociation cross sections and the effective formation crosssections of new species.The experiments will be performed at the ARIBE low energy beamline of GANILemploying 10 keV oxygen ions (O+ and O++) at ~80 K. The ices will be also by in-situ infraredspectroscopy (FTIR) in a transmission mode, mass spectrometry (QMS) and possibly by ex-situ gaschromatography (GCMS) in the case of room temperature residue formation. The ex-situ analysiswill be conduced inside the collaboration program established by prof. Sergio Pilling (Univap,Marina's dissertation advisor) and Prof. Uwe Meierhenrich (Nice University) with starting date atSeptember 1st, 2017 (FAPESP post-doct project #2016/22018-7). The data will be also comparedwith previous data obtained by our group at the GANIL. We hope this project helps to improve theunderstanding of physical-chemical parameter and chemical evolution of solar system ices as wellas other frozen space environments.