On the autoionization transitions in thallium atoms

A configuration interaction analysis of the absorption cross-section curve of thallium has been carried out on the autoionization transitions ²P_1/2⁰-⁴P_3/2 and ²P_1/2⁰-²D_3/2 and their associated photoionization continua. Intensity stealing from the E(D) continuum amounts to 80% of the oscillator strength for the ²P_1/2⁰-⁴P_3/2 transition and 5% for the ²P_1/2⁰-²D_3/2 transition. Application of the f-sum rule indicates that a considerable contribution to the oscillator strengths must lie to the high wave number side of the above autoionization transitions. Unperturbed photoionization cross-section values of 8.0 Mbn for the E(D) continuum and 1 7 Mbn for the E(S) continuum at the ionization threshold are indicated.