Integral Cross Sections for Electron Impact Excitation of Rydberg and Valence States of Molecular Nitrogen

We present integral cross sections (ICSs) for electron impact excitation of N$_{2}$ out of the ground state $X (v$=0), to the $b$, $c_{3}$, $o_{3}$, $b', c'_{4}$, $G$, and $F$ electronic states at incident energies ranging between 17.5 eV and 100 eV. The ICSs were derived from the differential cross sections (DCSs) of Khakoo \textit{et al}. [Phys. Rev. A \textbf{77}, 012704 (2008)], which were obtained by unfolding energy loss spectra in the $\sim $12-13.82 eV range. Recently, Heays \textit{et al}. [Phys. Rev. A \textbf{85}, 012705 (2012)] measured comparable higher resolution energy loss spectra, with a significantly different apparatus configuration, but in agreement with the Khakoo \textit{et al}. (2008) spectra. This latter additional effort provided further confidence in the accuracy of the DCSs upon which the present ICS results are based. Of the higher-lying states studied, five are singlet states that radiate to the ground state via dipole allowed transitions. These include the $b$ and $b'$ valence states and the $c'_{4}$ Rydberg state that give rise to the Birge-Hopfield I, II, and Carroll-Yoshino bands, respectively, all of which are observed in the atmospheres of Earth, Titan, and Triton. The $c_{3}$ and $o_{3}$ Rydberg states give rise to the Worley-Jenkins and Worley series of Rydberg bands, respectively. However, these emissions are not readily observed since predissociation for the $c_{3}$ and $o_{3}$ states approaches 100{\%}. As such, direct electron excitation measurements, such as those presented here are superior to standard (spontaneous) emission based measurements in this case.