Electron Irradiation of Astrophysical Ice Analogues: Implications for the Formations of Biomolecules on Enceladus.


Abstract: Here, we investigated the electron irradiation of astrophysical ice analogs in an Ultra-High Vacuum (UHV) chamber with base pressure of 3x10-11 torr. Gas was introduced to the chamber, then condensed on a sample holder, which was then irradiated with a 2keV electrons over various time intervals. Fourier Transform Infrared (FTIR) spectra were taken before and after each interval of irradiation, allowing us to monitor product formation with the ice. We then performed temperature programed desorption (TPD) while monitoring the desorbed products with a quadrupole mass spectrometer (QMS). Our work presents a better understanding of the dynamics involved in the irradiation of airless bodies in the solar system, and elucidates the intermediate reactions occurring during radiation induced processing of ices. We also present findings that could show how biomolecules, such as amino acids, form on the surface of Enceladus through the interaction of the magnetosphere with plume material from Enceladus.