Knowledge Bank

Two photon transitions form the metastable 3s[3/2]$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ level to ‘ns’ and ‘nd’ Rydberg levels of neon have been recorded for the first time in the optogalvanic spectrum between 500 and 548 nm. Both series converge to the lower ionization limit of neon at $173930cm-1$ and a relatively large quantum defect is observed for the ‘ns’ as compared to the ‘nd’ series. This work shows that one and two photon transitions in the same wavelength region can be separately recorded by properly choosing the experimental parameters and the Rydberg states involving ‘n’ upto 34 can be studied by optogalvanic technique.