Laser-induced fluorescence of NaK and the dissociated atoms

Abstract
Intensity distribution of both bound–bound and bound–continuum transitions of the NaK d 3Π1a 3Σ+ fluorescence has been analyzed by calculating Franck–Condon factors for the transitions. The potential curves of the d 3Π1 state and the dissociative continuum of the a 3Σ+ state have been estimated by comparing the observed and the calculated intensities, and the variation of the transition dipole moment with internuclear distance has been evaluated. Besides molecular fluorescence, the fluorescence of the D lines of Na and K atoms were observed. The absolute and the relative intensities of the atomic D1 and D2 lines have been found to be different between the Na and K atoms. The effects of a foreign gas on atomic D lines and their dependence on a frequency of excitation are studied, and the mechanism responsible for the atomic emission is examined.