Photoelectron study of the satellite ion states of HCl and the production of autoionizing chlorine atoms by photodissociation of HCl

The HCl + satellite states, in the energy range 20-31 eV, have been studied by photoelectron spectroscopy. The energy resolution achieved has allowed vibrational levels to be observed for the first time which has shown the two lowest lying states to be dissociative. The use of tunable VUV radiation has provided detailed information on resonance processes occurring in the region of the ionization thresholds for the satellite ion states. These processes include neutral photodissociation producing autoionising chlorine atoms. Some of the observed atomic states are optically forbidden in transitions from the ground state of the atom.