Autoionizing levels of beryllium from the multiconfiguration relativistic random-phase approximation

Autoionizing levels of beryllium near its first ionization threshold are investigated using the multiconfiguration relativistic random-phase approximation. The 2pns ¹P^∘₁ and 2pnd ¹P^∘₁ Rydberg series of doubly excited states manifest as autoionization resonances in the 2s photoionization cross section. Theoretical predictions and available experimental data are in excellent agreement within 0.05 eV.