Luminescence in Collisions of C⁺ Ions with N₂ Molecules

Abstract

Emission spectra ranging from 1900 to 4400 Å were observed for C⁺–N₂ collisions in the ion energy range 10–1000 eV. N₂⁺ first negative bands are always strongest over the energy range. Besides, CI(3s ¹P⁰), CII(3s ²P_1⁄2,3⁄2⁰), and N₂(C³Π_u) are found as excited products. Relative emission cross sections have been measured for all of these bands and lines over the ion energy range. It has been found that the cross sections of N₂⁺(B) have a sharp peak around E_LAB=20 eV and then again increase in the energy region above 100 eV, while the cross sections of the other emission rise monotonically from a few ten eV. A simple three-state model provides satisfactory explanation of the sharp peak of N₂⁺ 1 n bands.