Vibrationally resolved photoelectron-spin-polarization spectroscopy of HI molecules

The photoemission from HI is studied separately for different vibrational levels of the ${}_{}{}^2{}_{}{}^{}\mathrm{\Pi }$ final ionic states using spin-resolved photoelectron spectroscopy with circularly polarized light. Constant-ionic-state measurements of the cross sections σ and the polarization parameters A indicate that all channels are strongly influenced by autoionization resonances. By combining these data, sums of partial contributions to σ are analyzed in detail to obtain specific information on the coupling of the resonances to the outgoing partial waves ελ. Apart from generally similar trends, the results show pronounced variations for different vibrational levels.