The Astrophysical Journal · 1939 · 397 citations · 0 references
The effect of ionization of the surrounding atmosphere in broadening the high-series terms of the alkali spectra so that they form a continuum down to a quantum number n, is discussed theoretically. It is shown that the ion density is proportional to n<SUP>-7.5</SUP>. The effect of the mobility of the electrons is investigated.