2-PHOTON OPTOGALVANIC RYDBERG SPECTRA OF NEON

We report extensive new data on the single-colour two-photon optogalva nic spectra of neon in the visible region. The experimental method ena bles us to record a pure two-photon spectrum in a region which is full of one-photon transitions. A large number of two-photon transitions o riginating from two metastable 3s[3/2](2), 3s'[1/2](0) states and one non-metastable 3s[3/2](1) state of the 2p(5)3s configuration of neon h ave been recorded and arranged into 19 Rydberg series. The interchanne l interactions among the overlapping Rydberg series have been studied using the multichannel quantum defect theory.