These volumes contain the abstracts of invited and contributed papers presented at the X-82 Conference. full texts of invited papers will be published as a book in the American Institute of Physics Conference Proceedings series. Dominant themes are: energetic x-ray and radiationless transitions in atoms including solid-state, many-body, relativistic, and quantum-electrodynamic effects; x-ray scattering and bremsstrahlung; recent developments in atomic inner-shell and x-ray physics in materials science, astrophysics and nuclear physics, and novel sources of short-wavelength radiation. There are sessions devoted to the interface of atomic and nuclear physics, advances in photoelectron and Auger-electron spectroscopy, new insights in electron-atom and ion-atom interactions, and other topics that recently have been the subject of exceptionally productive research.

The physics of atomic inner shells has undergone significant advances in recent years. Fast computers and new experimental tools, notably syn chrotron-radiation sources and heavy-ion accelerators, have greatly enhan ced the scope of problems that are accessible. The level of research activity is growing substantially; added incentives are provided by the importance of inner-shell processes in such diverse areas as plasma studies, astrophysics, laser technology, biology, medicine, and materials science. The main reason for all this exciting activity in atomic inner-shell physics, to be sure, lies in the significance of the fundamental problems that are coming within grasp. The large energies of many inner-shell processes cause relativistic and quantum-electrodynamic effects to become strong. Unique opportunities exist for delicate tests of such phenomena as the screening of the electron self-energy and the limits of validity of the present form of the frequency-dependent Breit interaction, to name but two. The many-body problem, which pervades virtually all of physics, presents somewhat less intractable aspects in the atomic inner-shell regime: correlations are relatively weak so that they can be treated perturbatively, and the basic potential is simple and known! The dynamics of inner-shell processes are characterized by exceedingly short lifetimes and high transition rates that strain perturbation theory to its limits and obliterate the traditional separation of excitation and deexcitation. These factors are only now being explored, as are interference phenomena between the various channels.

See Document AD-A130 304 - page III Vol. 1.

The fields of X-Ray Spectroscopy in Atomic and Solid State Physics have undergone spectacular growth, sometimes rather anarchic, during the past decade. The old mold of X-ray spectroscopy has been burst, and this ASI provided an in-depth exploration of theory and recently developed techniques; however, some work still needs to be done to create a new frame and reduce anarchy in the field. The purpose of this Institute was to gather atomic and solid state physicists working in theoretical and new experimental techniques recently developed. The lectures were concerned with, among others, the following fields: theory of X-ray near-edge structure, XPS and AES with conventional and synchrotron radiation sources, PIXE, EXAFS, SEXAFS, XRF, SXS, and molecular spectroscopy. The Institute considered in detail some of these experimental tech niques and the pertinent theoretical interpretations by selecting an important list of lectures which summarize the scientific contents of the ASI. The truly international character of this NATO ASI, its size, and the high quality of the lecturers contributed to make this school a very fruitful scientific meeting. Two to four general lectures were given each working day and three afternoons were reserved for presentation of current work in the form of posters. We think that these poster presentations reflect the current research work of the participants.