Topics covered include: contribution of field-ionized Rydberg atoms to convoy electron spectra; microwave field ionization of fast Rydberg atoms; coherent Stark states in foil-excited fast Rydberg atoms; and equilibration lengths of K-Vacancy production in solids. (GHT).

Argonne's 5-MV Dynamitron accelerator is used to study the interactions of fast (MeV) atomic and molecular ions with matter. A unique feature of the apparatus is the exceptionally high resolution, in angle and time-of-flight, obtained in detecting particles emerging from the target. New imaging detector systems have been developed which allow detection of multiparticle events consisting of up to 12 particles. The work has as its main objective a general study of the interactions of fast charged particles with matter, but with the emphasis on those aspects that take advantage of the unique features inherent in employing molecular-ion beams (e.g., the feature that each molecular ion incident upon a solid target forms a tight cluster of atomic ions that remain correlated in space and time as they penetrate the target). In particular, these techniques have allowed the direct determination of the geometrical structures of the molecular ions entering the target, providing the first direct measure of the fully correlated nuclear densities within small molecules.

Experimental results are presented from high resolution studies of the energy- and angle-distributions for the break-up products that arise from the dissociation of a variety of fast molecular ions in thin carbon foils and in gases. The results for foil targets are compared with calculations based on a model for the polarization ''wakes'' induced in foils by the passage of fast charged projectiles. An example is given of the application of this type of dissociation measurement to the determination of a molecular structure--that of H3. Also measurements on the transmission of fast molecular ions through carbon foils are described and results presented on the transmission probabilities, energy losses and angular distributions of the transmitted ions.

Charged Particle and Photon Interactions with Matter offers in-depth perspectives on phenomena of ionization and excitation induced by charged particle and photon interactions with matter in vivo and in vitro. This reference probes concepts not only in radiation and photochemistry, but also in radiation physics, radiation biochemistry, and radiatio

This book provides an overview of the recent experimental and theoretical results on interactions of heavy ions with gaseous, solid and plasma targets from the perspective of atomic physics. The topics discussed comprise stopping power, multiple-electron loss and capture processes, equilibrium and non-equilibrium charge-state fractions in penetration of fast ion beams through matter including relativistic domain. It also addresses mean charge-states and equilibrium target thickness in ion-beam penetrations, isotope effects in low-energy electron capture, lifetimes of heavy ion beams, semi-empirical formulae for effective cross sections. The book is intended for researchers and graduate students working in atomic, plasma and accelerator physics.

There are many interesting aspects of the interactions of fast ions with matter that can be explored using molecular-ion projectiles. At high velocities, these projectiles dissociate rapidly (approx. 10−17 sec) upon entering a solid. Each projectile then results in a tight cluster of fragments which continue into the solid closely correlated in space and in time. Recent high-resolution studies on the trajectories of such fragments, their energy losses, their shifts in angle and energy, their charge states, etc., have produced a wealth of new information on such phenomena as stopping power, radiation damage, and the interactions of fast ions with the plasma oscillations they induce in solids. Studies with foil and gas targets have elucidated many aspects of the differences in interactions in solids and gases. The techniques used in these experiments show promise as a tool for studying molecular-ion structures.

The Workshop on Physics with Fast Molecular-Ion Beams was held in the Physics Division, Argonne National Laboratory on August 20 and 21, 1979. The meeting brought together representatives from several groups studying the interactions of fast (MeV) molecular-ion beams with matter. By keeping the Workshop program sharply focussed on current work related to the interactions of fast molecular ions, it was made possible for the participants to engage in vigorous and detailed discussions concerning such specialized topics as molecular-ion dissociation and transmission, wake effects, ionic charge states, cluster stopping powers, beam-foil spectroscopy, electron-emissions studies with molecular-ion beams, and molecular-ion structure determinations.