HYPERFINE-STRUCTURE IN THE B-X TRANSITION OF THE IODINE MOLECULE NEAR THE HEAD OF THE 12-0 BAND, BY LASER SPECTROSCOPY OF A PURE IODINE SUPERSONIC JET

Crossing a pure iodine supersonic jet with the output beam of a tunable monomode dye laser, we carried out a systematic high resolution survey of band-heads in the B-X transition of iodine. Working out the specific example of the 12-0 band head, we show that despite their apparent complexity, HFS patterns observed in transitions between low J levels can be interpreted rather easily when proper account is taken of the theory of second order effects. The high density of the beam allows the observation under high resolution of faint lines, such as ΔF = 0 and even ΔF = -ΔJ transitions, which permits the determination of eQq′ and eQq″ independently. © 1979.