BOUND-BOUND AND BOUND-FREE FLUORESCENCE FROM THE $A^{1}{\Sigma^{+}}_{u}$ STATE TO THE $X^{1}{\Sigma^{+}}_{g}$ STATES IN $NA_{2}$

Abstract

Using experimentally-based potential energy $curves^{1}$ and the theoretical transition $moment^{2}$, we report calculated bound-bound and bound-continuum radiative transition probabilities and calculated radiative lifetimes for several v', J', levels of the $A^{1}{\Sigma^{+}}_{u}$ state in $Na_{2}$. In the case of emission from the $A^{1}{\Sigma^{+}}_{u}$ (v' = 34, J' = 50) level, we present direct comparison with our recent laser-induced fluorescence $experiments^3$. Bound-bound Einstein A coefficients have been normalized to bound-free coefficients to show the continuity of the transition probability at the bound-continuum threshold. We demonstrate how the spectrum in the threshold vicinity provides a means to improve the value of the $X^{1}{\Sigma^{+}}_{g}$ ground state dissociation energy.