Experimental simulation of the effects of energetic particles (ions and electrons) on the surface of icy bodies in the Solar System: physicochemical transformation of ices mixtures containing H2O,CO2,CH4 (10:1:1)

Abstract

The aim of this project is to experimentally study the interaction between highlycharged ions with the mixture H2O,CO2,CH4(10:1:1) astrophysical ice analogs in physicochemical condition similar to the ones found in interstellar dust regions, comets, transneptunians objects (TNO) and moons (for example Enceladus). As a first step, we will analyze experimental data obtained previously by the group staff of the samples irradiated at 72 K by 15.7MeV O+5 . Themeasurements were performed at the heavy ion accelerator GANIL (Grand Accelerateur Nationald'Ions Lourds). A second experiment will be perform using fast electrons (1-5 keV) in the LASA laboratory at the UNIVAP of the Laboratory of astrochemistry and astrobiology LASA / UNIVAP (built with FAPESP grant). The analysis of both data sets will performed in-situ by employing infrared spectroscopy (FTIR) in a transmission mode, mass spectrometry (QMS) and possibly by gas chromatography (GCMS) in the case of experiments involving electrons. We will investigate the stability and chemical changes of these molecular species in space environments by determining the molecular dissociation cross sections and the formation of new species of cross sections. Theresults will identify dissociation processes and estimate half-life of these molecules in astrophysical scenarios. We hope this project helps to improve the understanding of physical-chemical parameter and chemical evolution of space environments. Given the importance of experimental work for understanding astrophysical scenarios and chemical complexity of spatial environments, we hope this project helps to improve the understanding of the physical chemistry of H2O,CO2,CH4 dustgrains, such composition has been observed in astronomical objects.