The autoionizing Rydberg series 3p1/2⁵n [K ]J(    0 5) of Ar: the influence of many-electron effects on the resonance widths

Theoretical results for the autoionization dynamics of 3p 1/2 5 n ℓ' Rydberg states of Ar atoms into the 3p 3/2 5 εℓ continua are presented for ℓ' = 0–5. The quantum defects and the reduced widths of these resonances were calculated within the configuration interaction Pauli–Fock approach including core polarization. The most significant many-electron effects influencing the decay dynamics are the polarization of the atomic core by the Rydberg electron and photoelectron, the correlational decrease of the Coulomb interaction and the interaction between the Rydberg states. For ℓ' = 0, 2 and 4 (where reliable measurements exist) the calculated reduced resonance widths agree with the experimental results to within 20%.