Laser spectroscopy of Na i quartets

Abstract

By using a pulsed hollow-cathode discharge, metastable atoms are produced in the (2${p}^{5}$3s3p)${}^{4}$${D}_{7/2}$ and (2${p}^{5}$3s3p)${}^{4}$${S}_{3/2}$ levels of Na i. A tunable laser is used to excite these atoms to levels in the 2${p}^{5}$3s3d and 2${p}^{5}$3s4s configurations, and thereby to establish a partial Grotrian diagram for the quartet system. Several possible Na i xuv laser systems are described.