Rydberg spectroscopy of H2 via stepwise resonant two-photon ion-pair (H++H−) production

Abstract

High-resolution spectra of new Rydberg states of ${\mathrm{H}}_2$ in the extreme uv region were obtained by two-step doubly resonant excitation followed by ${\mathrm{H}}^{\mathrm{-}}$-ion detection. Resolved Fano-line profiles showing a sign reversal of the profile index along the Rydberg series were observed for the first time in ${\mathrm{H}}_2$. Dynamical information such as lifetimes and relative transition strengths was also derived.