Determination of the Hyperfine Structure of Atomic Nitrogen by Optical Orientation

In the method of optical orientation with spin exchange the problems of dissociation of molecular nitrogen and detecting nitrogen atoms are simply and effectively solved: fractional dissociation of only about one part in 10/sup 7/ is required, and detection is effected with a photocell. New precise values for the hyperfine intervals of the ground state of atomic nitrogen are reported. The experiment is performed in a 500 cc flask filled with N/sub 2/ at a pressure or 3.0 cm Hg, He at 0.5 Hg, and Rb vapor at a temperature of 50 C. Nitrogen atoms are produced by a pulsed discharge between aluminum electrodes mounted along a diameter of the bulb. (W.D.M.)