Physics
The role of low-energy (≤ 20 eV) electrons in astrochemistry
Document Type
Article
Abstract
UV photon-driven condensed phase cosmic ice reactions have been the main focus in understanding the extraterrestrial synthesis of complex organic molecules. Low-energy (≤ 20 eV) electron-induced reactions, on the other hand, have been largely ignored. In this article, we review studies employing surface science techniques to study low-energy electron-induced condensed phase reactions relevant to astrochemistry. In particular, we show that low-energy electron irradiation of methanol ices leads to the synthesis of many of the same complex molecules formed through UV irradiation. Moreover, our results are qualitatively consistent with the hypothesis that high-energy condensed phase radiolysis is mediated by low-energy electron-induced reactions. In addition, due to the numbers of available low-energy secondary electrons resulting from the interaction of high-energy radiation with matter as well as differences between electron- and photon-induced processes, low-energy electron-induced reactions are perhaps as, or even more, effective than photon-induced reactions in initiating condensed-phase chemical reactions in the interstellar medium. Consequently, we illustrate a need for astrochemical models to include the details of electron-induced reactions in addition to those driven by UV photons. Finally, we show that low-energy electron-induced reactions may lead to the production of unique molecular species that could serve as tracer molecules for electron-induced condensed phase reactions in the interstellar medium.
Publication Title
Surface Science
Publication Date
10-2016
Volume
652
First Page
26
Last Page
32
ISSN
0039-6028
DOI
10.1016/j.susc.2016.03.012
Keywords
astrochemistry, cosmic ices, infrared reflection absorption spectroscopy, low-energy electrons, synthesis of prebiotic molecules, temperature programmed desorption
Repository Citation
Boyer, Michael C.; Rivas, Nathalie; Tran, Audrey A.; Verish, Clarissa A.; and Arumainayagam, Christopher R., "The role of low-energy (≤ 20 eV) electrons in astrochemistry" (2016). Physics. 62.
https://commons.clarku.edu/faculty_physics/62
