Gas phase high temperature photoelectron spectroscopy

The HeI photoelectron spectrum of atomic gallium has been recorded. Bands associated with ionization from both the J = 1/2 ground state and J = 3/2 excited state arising from the 4s 2 4p 1 configuration have been observed. The NeI spectrum of the (4p)-1 ionization is used to estimate the excitation temperature of gallium as 1100 ± 150 K and evidence is presented to show that the HeI spectrum is perturbed by an auto-ionization process from the J = 3/2 excited state. A simple intermediate coupling model is developed and shown to be useful in the prediction of relative band intensities.