The doublet oscillator-strength ratios ρ<sub><i>n</i></sub> of the cesium principal series (6<sup>2</sup><i>S</i><sub>1/2-</sub><i>n</i><sup>2</sup><i>P</i><sub>3/2,1/2</sub>) have been measured for principal quantum number <i>n</i> = 7–21. Both emission and absorption spectroscopic measurements were performed with a 9.1-m focal-length spectrometer. The results show that ρ<sub><i>n</i></sub> increases monotonically with <i>n</i>. Discrepancies between emission and absorption results are attributed to collisional mixing of the excited-state populations. Oscillator strengths of both fine structure lines were obtained from the absorption measurements. These agree substantially with similar work by Lorenzen and Niemax [J. Phys. B 11, L723 (1978)]. Fano <i>X</i> parameters derived from the measured results are found to decrease monotonically with <i>n</i>. The value of <i>X</i>, extrapolated to the ionization potential, is 2.05 ± 0.03, in good agreement with recent laser-excited atomic-beam results of Raimond <i>et al.</i> [J. Phys. B 11, L765 (1978)]. This makes unlikely the existence of a pole of ρ<sub><i>n</i></sub> in the discrete spectrum, which requires that <i>X</i> have the value 2.
© 1981 Optical Society of America
Chun-Sing O, G. F. Fülöp, O. Redi, and H. H. Stroke, "Emission and absorption measurements of the anomalous cesium principal-series doublet oscillator-strength ratios," J. Opt. Soc. Am. 71, 1072-1079 (1981)