ROTATIONALLY RESOLVED SINGLE-PHOTON IONIZATION OF HCL AND DCL

The rotationally resolved photoionization yields of jet-cooled HCI and DCI have been measured in the energy range between their spin-orbit s plit 2PI ionic thresholds. For single-photon excitation, narrow-band v uv radiation is generated by resonant frequency mixing. The spectra ar e complex due to an interaction of autoionizing resonances belonging t o series converging to different rotational states of the ion core. Th is is taken into account using the multichannel quantum defect theory in a treatment capable to handle a transition m angular momentum coupl ing from Hund's case (c) to case (e). Even for Rydberg orders n > 35 t he experimental data cannot be explained using a pure case (e) picture .