MICROWAVE MEASUREMENTS OF D-F-G-H INTERVALS AND D AND F FINE-STRUCTURE OF SODIUM RYDBERG STATES

Eighty-one microwave resonances in Na Rydberg states n = 21-35 between d, f, g, and h states have been accurately measured. Among them 43 transitions are first-time measurements, and 38 transitions have been improved, primarily by the elimination of stray electric and magnetic fields, compared with previous measurements. For the d-f transitions, the measured intervals and d-state fine-structure splittings are a factor of 10 more precise; for d-g and d-h series, the measured intervals are a factor of 3 more precise than before. The nf-state fine-structure splittings in Na for n =21-29 have also been accurately measured, and the conclusion that the Na f-state fine-structure splitting nf5/2-nf7/5 is about 5% smaller than the hydrogen f-state fine-structure interval is confirmed through n = 29.