Determination of oscillator strengths from the self-absorption of resonance radiation in rare gases—II. Neon and argon

Abstract

A previously developed method, based on the self-absorption of resonance radiation, is used to derive oscillator strengths for fourteen resonance transitions of neon and argon. Electron beam excitation of the atoms is used to produce the resonance radiation, which is partly absorbed in the gas between the beam and the spectrometer. A v.u.v. spectrometer is employed to record the radiation intensities as a function of gas pressure. Oscillator strengths are derived from the measurements by using a simple formalism. The influence of recoil effects (as a consequence of the excitation process) on the shape of the spectral emission lines and thereby on the transmission is checked by detailed numerical calculations. Special attention is paid to the determination of the quantities relevant in absorption measurements, i.e. the temperature, the absorption length and the number density of the atoms. The oscillator strengths obtained are compared with results from other experiments of various types (particularly forward inelastic electron scattering, for which on the whole good agreement with the present results exists) and from theoretical calculations.