Radiolysis and sputtering of carbon dioxide ice induced by swift Ti, Ni, and Xe ions

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Beam interactions with materials and atoms, 2015-12, Vol.365, p.477-481
• Main Authors: Mejía, C., Bender, M., Severin, D., Trautmann, C., Boduch, Ph, Bordalo, V., Domaracka, A., Lv, X.Y., Martinez, R., Rothard, H.
• Format: Article
• Language: English
• Subjects: Astrophysical ices; Astrophysics; Beam interactions; Carbon dioxide; Condensed Matter; Electronics; Heavy ions; Materials Science; Nickel; Physics; Radiation chemistry; Sciences of the Universe; Solar system; Sputtering; Stopping power; Titanium
• ISSN: 0168-583X; 1872-9584; 1872-9584; 0168-583X
• DOI: 10.1016/j.nimb.2015.09.039

Solid carbon dioxide (CO2) is found in several bodies of the solar system, the interstellar medium (ISM) and young stellar objects, where it is exposed to cosmic and stellar wind radiation. Here, the chemical and physical modifications induced by heavy ion irradiation of pure solid CO2 at low temperature (T=15–30K) are analyzed. The experiments were performed with Ti (550MeV) and Xe (630MeV) ions at the UNILAC of GSI/Darmstadt and with Ni ions (46 and 52MeV) at IRRSUD of GANIL/Caen. The evolution of the thin CO2 ice films (deposited on a CsI window) was monitored by mid-infrared absorption spectroscopy (FTIR). The dissociation rate of CO2, determined from the fluence dependence of the IR absorption peak intensity, is found to be proportional to the electronic stopping power Se. We also confirm that the sputtering yield shows a quadric increase with electronic stopping power. Furthermore, the production rates of daughter molecules such as CO, CO3 and O3 were found to be linear in Se.