The Advanced Study Institute on "Photoionization and Other Probes of
Many-Electron Interactions" was held at the Centre "Les Cigales" in
Carry-Ie-Rouet (France), from August 31st till September 13th 1975. The
Institute was sponsored by the Scienti- fic Affairs Division of NATO.
The "Centre National de la Recher- che Scientifique" (France) gave also
partial support to the French participants and the National Science
Foundation (U. S . A. ) to the American participants. A total of 18
lecturers, and 54 students selected among more than 120 applicants,
attended the Institute. Over the last few years, substantial progress
has been made in the experimental study of photon- or electron
interactions with atoms. In particular, the g. rowing number of
facilities created to use the synchrotron radiation makes now possible
the realization of new types of experiments. The accumulation of new
results showed clearly it was necessary to introduce electron
correlations in the theoretical models in order to explain the existence
and the probability of a large number of processes, in particular
multiple processes. Thus large progress has also been made in the
theore- tical description of the excitation of the electronic systems
and their interactions. It was the purpose of this Institute to bring
together theoreticians and experimentalists in order to provide an
opportunity to present in details the state of the art, in experiment as
well as in theory, and to favor discussions on future experimen- tal and
theoretical studies.