Polarizability of Pb III from spectroscopy of high-L Rydberg states of Pb II

Using the Resonant Excitation Stark Ionization Spectroscopy technique[1], we measured resolved fine structure components of the n=20 to n'=52 transition in Pb$^{+}$, and determined the polarizability of Pb$^{2+}$. A critical part of the measurement consists of the determination of the L-value of one or more of the resolved excitation peaks. These measurements were motivated by a discrepancy between previous polarizability determinations based on contrasting methods[2]. [1] S.R. Lundeen and C.W. Fehrenbach, Phys. Rev. A 75, 032523 (2007)[2] Nicholas Reshetnikov, et. al., Physica Scripta 77, 015301 (2008).