Fine-structure branching in the near-threshold photodissociation of NaK(X 1 Sigma +-B 1 Pi ).

Abstract

We have measured the ${\mathit{X}}^{1}$${\mathrm{\ensuremath{\Sigma}}}^{+}$--B $^{1}\mathrm{\ensuremath{\Pi}}$ bound-free molecular photodissociation profile of NaK under molecular-beam conditions. The dissociation results in excited ${\mathrm{K}}^{\mathrm{*}}$(4 $^{2}$P). We have measured the ${\mathit{D}}_{1}$/${\mathit{D}}_{2}$ fine-structure branching ratio; this ratio is a strong function of wavelength ranging from near zero to ${\mathit{D}}_{1}$/${\mathit{D}}_{2}$\ensuremath{\simeq}25% as the laser is tuned through the bound-free absorption profile.