The effect of longitudinal plasma oscillations on atomic spectra is examined. It is shown that they should give rise to satellite lines, disposed symmetrically in pairs about a forbidden line and separated from it by ${\Omega }_p$, the plasma frequency. Discussion is given of the circumstances under which these satellites should be strong enough to be observed. Their observation would amount to a measurement of the frequency and intensity of plasma oscillations.

• Received 27 February 1961

DOI:https://doi.org/10.1103/PhysRev.123.25