Dynamic Processes in Be Star Atmospheres. V. Helium Line Emissions from the Outer Atmosphere of λ Eridani

Abstract

The He I lines of the mild B2e star j Eri often exhibit rapid, small-amplitude emissions that can occur at random places in their photospheric lines, even when the star is in a "" nonemission state. New simultaneous observations of the triplet j5876 and singlet j6678 lines show that the emission ratio for these lines is near unity, contrary to the predictions of either non-LTE model atmospheres or nebular recombination theory.