Knowledge Bank

Ion beams of $NaCl-,NaBr-$, and $NaI-$ are crossed with the photon beam of a tunable dye laser. The detached electrons and the resulting neutrals from the process $$NaX^{-} + h\nu = NaX + e^{-}$$ are monitored as a function of photon energy. The resulting photodet achment spectra show evidence for detachment via an excited state of the negative ion embedded in the detachment continuum. $$NaX^{-}(^{2}{\Sigma} ) + h\nu \rightarrow {NaX^{-}(^{2}\Pi)} \rightarrow NaX({^{1}}\Sigma) + e^{-}.$$