HIGH-RESOLUTION ELECTRON-IMPACT EMISSION SPECTRA AND VIBRATIONAL EMISSION CROSS SECTIONS FROM 330–1100 nm FOR N2

Abstract

ABSTRACT Electron-impact emission cross sections for N2 were measured in the wavelength range of 330–1100 nm at 25 eV and 100 eV impact energies. Cross sections of several molecular emission bands of the first positive band system B 3Π g +(ν′) → A 3Σ g +(ν″) and the second positive band system C 3Π u (ν′) → B 3Π g (ν″) of N2, the first negative band (1NB) system B 2Σ u +(ν′) → X 2Σ g +(ν″) and Meinel band system A 2Π u (ν′) → X 2Σ g +(ν″) of N2 + ions as well as line emissions of N (N i) and N+ (N ii) in the visible–optical–near-IR wavelength range reported in this work were measured for the first time in a single experimental setup at high spectral resolving power (λ/Δλ ≈ 10000) under single-collision-scattering geometry and optically thin conditions. Rotational emission lines of N2 and N2 + were observed for strong emission bands at a gas temperature of about 300 K. The absolute cross section of the strongest (0,0) vibrational band at 391.43 nm of 1NB was determined using the standard Hα emission cross sections of H2 by electron impact at both 25 eV and 100 eV electron-impact energies, and the cross sections for the remainder of the emissions were determined using (0,0) 1NB value. A comparison of the present emission cross sections with the earlier published data from both electron energy loss and electron-impact-induced fluorescence emission is discussed.