Low-Energy Proton Bombardment of Carbon Dioxide

Abstract

Carbon dioxide, the major constituent of Martian and Venusian atmospheres, was bombarded by protons having energy in the range 0.5 to 2 keV. The excited spectra in order of intensity consisted of Angstrom and 3PG system of CO₂ comet tail bands of CO⁺ and H_ɑ, and H_β lines. It was observed that the intensities of Angstrom and 3PG bands increase and those of comet tail bands of CO⁺ and H_β line decrease with proton energy. The excitation of the above bands has been attributed to the dissociation of CO₂ and charge exchange with protons. The spectra excited by proton bombardment were compared with those obtained by microwave discharge of CO₂ and their differences explained.