FINE AND HYPERFINE-STRUCTURE OF THE TRIPLET-STATES 1(3)SIGMA(U)(-2 MOLECULE() AND 1(3)SIGMA(G)(+) OF THE NA)

The 1(3) Sigma(g)(+) <-- 1(3) Sigma(u)(+) absorption spectrum of Na-2 has been measured with sub-Doppler resolution in a collimated cold arg on beam seeded with sodium vapor, using resonant two-photon ionization with a cw single mode Ti-sapphire laser and a cw argon laser. The spe ctrally resolved fine and hyperfine structure of the rotational lines allowed the determination of the spin-spin interaction constants lambd a '' = - 1294 MHz, lambda' = -529 MHz, the spin-rotation constants gam ma '' = 42 MHz, gamma' = 2.6 MHz and the Fermi contact constants b '' = 293 MHz, b' = 223 MHz. All the molecular constants of both electroni c states obtained from this and from former work are compiled and comp ared with theoretical values.