Strong nonmonopole shake transitions in the Br 3d-1np? (n=6-9) resonant Auger spectra of HBr

The high-resolution resonant Auger spectra of Br 3d-1np? (n=6-9) in HBr are presented. These spectra are extremely complex, with very intense shake and vibrational features. Especially surprising is the observation of at least five intense Auger lines for each intermediate state due to transitions into different final-state configurations; this number of lines can only be explained with strong nonmonopole transitions which prevent obtaining information on the symmetry character of the excited-state orbital in the intermediate state. They are explained in a semiclassical model with the interaction between the Auger electron and the excited Rydberg electron.