Observation and Charcterization of the Fluorescence Decay of the 2s2p6 np 1Po Excited States of Neon

Fluorescence decay of the 2s2p6np 1Po excited states of neon has been observed directly for the first time. This process has also been observed indirectly by threshold photoelectron spectroscopy and in electron/photon coincidences. The measurements have allowed this weak decay channel to be characterized and branching ratios derived. The fluorescence excitation spectrum is well described by a simple Rydberg model that highlights the interplay and competition between the decay channels of autoionization and fluorescence.