A PHOTOELECTRON STUDY OF THE ROTATIONAL SELECTIVITY OF VIBRATIONAL AUTOIONIZATION OF H-2

Rotationally selective vibrational autoionization in molecular hydroge n has been investigated using two-dimensional photoelectron spectrosco py. Measurements of electron yield as a function of both electron and photon energy have been carried out using tuneable synchrotron VUV rad iation between the v = 0 and v = 1 vibrational thresholds of H-2(+) X (2) Sigma(g)(+), 15.45-15.70 eV. Constant rotational transition energy spectra have been extracted revealing the decay routes of autoionizin g states. No large changes in the rotational quantum number of the ion core during autoionization were observed.