LINEAR ABSORPTION-MEASUREMENTS OF PRESSURE BROADENING IN NEON

Self-broadening of the neon lines lambda-585.2 nm and lambda-667.8 nm at 77 K and 300 K has been studied by the linear absorption technique using a tunable laser. The natural mixture of neon isotopes was excited in a weak DC discharge. The broadening is expected to be due mainly to the resonance interaction since the lower level of both lines is the strong resonance level 1s2. The radiation width of this level was derived from the Lorentzian widths of the lines extrapolated to zero density, leading to a resonance oscillator strength of 0.158(10). The measured broadening constants of lambda-585.2 nm and lambda-667.8 nm respectively were, in units of 10(23) MHz m3 atom-1, 77 K: 205(5), 204(9) and 300 K: 186(11), 191(6), where the quoted errors represent only statistical uncertainty. Pure resonance broadening would give the value 188(7). A slight curvature was detected in the broadening of both lines at the lower temperature.