Photoionization of atomic iodine and atomic tellurium

Mass-analyzed photoionization spectra have been obtained from beams of atomic iodine and atomic tellurium from their respective ionization thresholds to approx.19 eV. In each instance, the ionization thresholds are confirmed. For iodine, most of the features in the autoionization resonance spectrum have been identified and assigned to several s- and d-like Rydberg series converging to the higher-ionization limits /sup 3/P/sub 0/, /sup 3/P/sub 1/, /sup 1/D/sub 2/, and /sup 1/S/sub 0/ of the 5s/sup 2/5p/sup 4/ configuration. For tellurium we also observe autoionization resonance features assigned to s- and d-like Rydberg series converging to the higher-ionization limits /sup 2/D/sub 3/2/, /sup 2/D/sub 5/2/, /sup 2/P/sub 1/2/, and /sup 2/P/sub 3/2/ of the 5s/sup 2/5p/sup 3/ configuration. In addition, a window-resonance series and additional peaks have been assigned as converging to the 5s5p/sup 4/ /sup 4/P/sub 5/2/ state of Te/sup +/, with quantum defect of approx.0.5 (modulo 1). In both elements, the d-like series exhibits anomalous resonance profiles similar to those in the heavier noble gases, with quantum defects of approx.0.4 (modulo 1). The s-like series has quantum defects of approx.0.0 (modulo 1). Some comparisons are made with many-body calculations on the related chlorine atom.