Configuration Interaction Effect on Diamagnetic Phenomena in Atoms: Strong Mixing and Landau Regions

We present a systematic densitometer mapping of diamagnetic effects on the principal series of Ba and Sr in absorption, with magnetic fields up to 4.7 T. The n- and l-mixing spectra are resolved in both σ- and π-polarization while the quasi-Landau resonances are observed near and above the ionization limit only in σ-polarization. Configuration interaction produces striking differences in the intensities and spacings of the n- and l-mixed spectra while only the shapes of the quasi-Landau resonances depend on the atomic systems.