Integral Cross Sections for the Electron Impact Excitation of Molecular Nitrogen

Integral cross sections (ICSs) for the electron impact excitation of the X $^{1} \Sigma_{g}^{+}$ (v$^{\prime\prime}$=0) ground level to the a$^{\prime\prime}$ $^{1}\Sigma$$_{g}^{+}$, b $^{1}\Pi _{u}$, c $^{1}\Pi _{u}$, o $^{1}\Pi _{u}$, b$^{\prime}$ $^{1}\Sigma$$_{u}^{+}$, c$_{4}^{\prime}$ $^{1}\Sigma$$_{u}^{+}$, G $^{3}\Pi _{u}$, and F $^{3}\Pi_{u}$ states of N$_{2}$ are reported at incident energies of 17.5eV, 20eV, 30eV, 50eV, and 100eV. The ICSs were obtained from integrating recent differential cross sections, which were obtained by unfolding new energy-loss spectra taken at electron scattering angles ranging from $2^{\circ}$ to $130^{\circ}$. The analysis of the spectra followed a different algorithm from that employed in a previous study of N$_{2}$ for the valence states by Khakoo \textit{et al.} [Physical Review A \textbf{71}, 062703 (2005)], since the $^{1}\Pi_{u}$ and $^{1}\Sigma $$_{u}^{+}$ states form a strongly-interacting Rydberg-valence series. The present results are compared to existing cross sections.