Laser photodetachment measurement of the electron affinity of atomic oxygen

Abstract

The electron affinity of atomic oxygen, an important calibration standard in negative-ion photoelectron spectroscopy, has been determined by tunable-laser photodetachment in a coaxial laser--ion-beam spectrometer to be 11 784.645\ifmmode\pm\else\textpm\fi{}0.006 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$. In addition, the spin-orbit splitting between the $^{2}\mathrm{P}_{3/2}$ and $^{2}\mathrm{P}_{1/2}$ states of ${\mathrm{O}}^{\mathrm{\ensuremath{-}}}$ was found to be 177.13\ifmmode\pm\else\textpm\fi{}0.05 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$.