Probing the KII 3p54p fine structure by photoelectron spectroscopy of laser-excited potassium

Photoelectron spectra of atomic potassium excited by laser optical pumping into the 3p 6 4p 2 P 1/2 and 2 P 3/2 states are measured with high-energy resolution. The relative intensities of the 3p 5 4p fine-structure lines depend strongly on the initial excitation to one of the 4p spin–orbit components. Similar to the case of sodium, dynamically and quasiforbidden transitions are observed in the photoelectron spectra of potassium. The theoretical predictions of the generalized geometrical model are in excellent agreement with the experimental data.