Synthesis of solid organic compounds by microwave plasma ionization of gas
We develop a new experiment of plasma ionization of gas mixtures in a low pressure cavity, based on our past experience at CRPG (Kuga et al. 2014, Kuga et al. 2015). It consists of a glass line evacuated in secondary vacuum and flown with gas mixtures. Gas flowing through a quartz tube is ionized by a microwave (2.45 GHz) plasma reactor. During ionization, C-rich films grow onto the glass wall and are then recovered for chemical characterization and isotope analysis
We plan to ionize H2-CO-N2 mixtures +/- noble gases akin to the protosolar composition, to investigate (i) potential mass-dependent isotope fractionation (IF) (H, N) and mass-independent isotope fractionation (MIF); (ii) origin of noble gas isotope fractionation. We shall also ionize CO2-N2 mixtures +/- H2, CH4, noble gases akin to the Early Earth/Mars atmospheric compositions, to investigate (i) the origin of the Xe paradox, and (ii) stable isotope fractionation in the context of the Martian atmosphere
The elemental composition and molecular structure of the run products will be determined in collaboration with S. Derenne (UPMC Paris). CRPG is a centre of excellence for geochemical analysis, including stable isotopes and noble gases. CRPG is hosting two large radius Cameca 1280 ion probes, and the synthesized material will be analyzed by ion imaging to search for stable isotope (H, C, N, O) anomalies (“hot spots”), a method largely developed at CRPG. The bulk isotope compositions of C and N will be determined at the stable isotope laboratory of CRPG with a dedicated analyzer.