The Line Spectra of Helium in Gaseous Nebulae

Abstract

The level populations of neutral helium are calculated for conditions typical of gaseous nebulae. Full collisional redistribution of angular momentum and energy is included, and accurate helium atomic data are used throughout. Intensities of the most important singlet and triplet line series are presented for |$n\leqslant\,25\cdot$| It is suggested that the collisional excitation of |${3}^{3}\,D\,\text{and}\,{4}^{3}D$| is overestimated in the calculations of Cox & Daltabuit.