Transition probabilities of the3p−3stransitions of Ne i

Transition probabilities for the $3p-3s$ array of Ne i have been measured in emission from a glow discharge containing a He-Ne-Ar mixture. The neon spontaneous emission at 632.8 nm ($3s_2-2\mathrm{}{p}_4$) was taken as the reference line and the emission intensities of the $2p_i-1\mathrm{}{s}_j$ lines were compared with it to obtain the relative transition probabilities $\frac{A(2\mathrm{}{p}_i-1\mathrm{}{s}_j)}{A_{632.8}}$. The discharge condition was carefully controlled so that the ratio of the populations of the $3s_2$ and a given $2p_i$ level was precisely equal to the ratio of the statistical weights of the energy levels: $\frac{N\left(3\mathrm{}{s}_2\right)}{N\left(2\mathrm{}{p}_i\right)}=\frac{g\left(3\mathrm{}{s}_2\right)}{g\left(2\mathrm{}{p}_i\right)}$, eliminating two population unknowns encountered in an ordinary gas discharge. The relative $A$ values were then converted to the absolute values by means of the accurate value of $A_{632.8}$, which was obtained in our recent measurements. The results were subjected to extensive comparisons with other experimental data of Bridges and Wiese, of Bennett and Kindlmann, and the intermediate coupling calculations by Mehlhorn and by Feneuille et al. Excellent agreement was observed throughout between these data sets and our results. The following has been found: Our results are more consistent with the $J$-file-sum rule than any other experimental data; our relative line strengths are in excellent agreement with the theoretical calculations of Feneuille et al.; our radial transition integral ${\sigma }^2$ exhibits least variations over different $2p$ levels—its weighted average has been found to be 6.66±0.02 (a.u.) on an absolute basis, which is very close to the value obtained from the Coulomb approximation; and our transition-probability sums are in excellent agreement with those evaluated from the intermediate coupling calculations combined with the Coulomb approximation. Based on these findings and the error analysis, we estimate the uncertainty of our $A$ values, except for a few weak lines, to be 2% on the relative scale and 6% on the absolute scale. Also, a discussion is given concerning the extent of configuration interaction on the $2p^{5}3p$ states.