The optical emission-line background and accompanying emissions at ultraviolet, infrared, and millimeter wavelengths

Abstract

The warm ionized component of the interstellar medium, revealed primarily by its faint line emission at optical wavelengths, must be a source of continuum and line emission in other spectral bands, potentially impacting the interpretation of background observations at radio, infrared, ultraviolet, and even γ-ray wavelengths. From the intensities of the optical lines it is possible to predict the intensities at high Galactic latitudes of the associated [N II] 122 and 205 μm, [C II] 158 μm, and [Ar II] 7.0 μm infrared lines, and the hydrogen two-photon and free-free continuum at far-ultraviolet and millimeter wavelengths, respectively