Ionization and Energy Pooling in Laser-Excited Na Vapor

Abstract

We have observed ion formation (both ${\mathrm{Na}}^{+}$ and ${\mathrm{Na}}_2^{+}$) and radiation from high-lying Na states when low-density vapor (∼${10}^{13}$ ${\mathrm{cm}}^{-3\mathrm{}}$) is irradiated with a cw dye laser tuned to one of the $D$ lines. The ${\mathrm{Na}}^{+}$ ions probably result from photodissociation of ${\mathrm{Na}}_2^{+}$ formed by $\mathrm{Na}\mathrm{}\left(3p\right)-\mathrm{Na}\mathrm{}\left(3p\right)\mathrm{}$ associative ionization, while the high-lying radiating states are formed in energy-pooling reactions.