Ammonia ices under low-energy electron irradiation - Towards quantitative desorption rates and effective cross sections

Low-energy (< 20 eV) electron processing of NH3 multilayer films, systems of interest in astrochemistry, leads to significant NH3 desorption, fragmentation, and to a complex chemistry arising from recombination and secondary processes induced by reactive products. Quantitative desorption rates of neutral species and effective cross sections for selected processes were obtained by combining three surface-sensitive techniques: High Resolution Electron-Energy Loss Spectroscopy (HREELS), Temperature Programmed Desorption (TPD) and Electron Stimulated Desorption (ESD) of neutral species.