HYPERFINE-STRUCTURE OF THE NAK A 3-SIGMA+ STATE - INTERACTION OF AN ELECTRON-SPIN WITH THE SODIUM AND POTASSIUM NUCLEAR SPINS

The hyperfine structures of the NaK a 3SIGMA+ state are observed for the first time by using a Doppler-free spectroscopy named perturbation facilitated polarization (PFP) spectroscopy. The hyperfine constants A(Na) and A(K) of the a 3SIGMA+ (v = 4, 5, 9, and 12) levels are determined. The observed hyperfine splittings are found to be well explained by the Fermi contact interactions of an electron spin with the sodium and potassium nuclear spins. The intensities and signs of the PFP spectra are calculated by using the determined hyperfine constants, and the results also agree with the observed ones. From the width of the observed spectra, energies of the spin-spin and spin-rotation interactions are obtained to be <5 X 10(-3) and 5 X 10(-5) cm-1, respectively.