A new technique for levitating solid particles inside a vacuum chamber is developed using a proton beam. This new technique differs from the classical laser-levitation technique invented by Ashkin in that it does not heat up light-absorbing levitated particles to vaporization. This unique property of the method will make it possible to levitate real interplanetary dust particles in a vacuum chamber and study their spin-up dynamics in a ground-based laboratory. It is found that a flux of protons from a proton gun of ~1015 cm–2 sec–1 is needed to levitate a 10-mm particle. Confinement of the levitated particle can be achieved by a Z or θ pinch to create a gravity well, or by making the beam profile doughnut in shape.

Evidence of gain in a recombining Z-pinch plasma has been obtained at 52 and 49.8 nm. The amplified XUV radiation originated from the 4f-3d and the 4d-3p transitions of Lilike oxygen, OVI. The plasmas were generated in a small diameter Z-pinch discharge with moderate currents of 40 kA. The gain coefficient was determined by variation of the pinch tube length, leading to a gain-length product of 2.5 (4f-3d) and of 2.2 (4d-3p) for a length of 9 cm.

Evidence will first be presented in favor of the usefulness of coordination number-dependent equations of state of metallic plasmas. After some theoretical discussion of the way such an equation of state may be related to dimer properties, with specific regard to Na and Al, critical point predictions for the alkalis will be brought into contact with experiments. In this context, some results on W will also be surveyed. Structural properties, static and dynamic, will then be considered in relation to transport in both Cu and H plasmas. This will embrace experiments on electrical resistivity in both examples. For H, a simple inference can be extracted about the structure factor, and the discussion will finally be generalized to treat the metalization of solid H.

This paper presents the results of a theoretical investigation of a laser-supported detonation wave (LDW) in a transverse magnetic field. A 1D problem of a steady-state wavefront structure is considered. The magnetic structure of the LDW is determined. Specific attention is focused on the stability conditions of a shock wavefront. The value of the induced (downstream) electric field strength is obtained from numerical calculations. The possibility of direct conversion of laser radiation energy into electricity in optical discharge plasma moving across an external magnetic field is considered. Such a device could be used in the energy supply systems of space vehicles.

High-intensity electron beams could be focused in low-frequency RF accelerators and induction linear accelerators by adding transverse components to the accelerating electric field. Calculations with a 3D code show that quasielectrostatic focusing is sufficient to transport kiloampere electron beams in RF accelerators and the high-energy sections of induction accelerators. The elimination of conventional magnetic focusing systems could lead to reductions in the volume and weight of high-current electron accelerators. Two novel quadrupole geometries are investigated: a periodic array of spherical electrodes with alternating displacements and a set of plate electrodes with elliptical apertures.

The stopping at low (V < Vth) and high (V ≤ Vth) velocity, of N strongly correlated ion debris is investigated for the case of a dense and classical electron target. The considered topologies of cluster projectile charges are taken cubic like, and circular, respectively. A specific emphasis is given to the N-dependence, and also to the topological features of the corresponding enhanced correlated stopping.

A brief discussion of the standard theory of line broadening is presented together with an analysis of selected laser-driven implosion experiments. The effect of improved theoretical procedures on experimental analysis is discussed. In particular, we consider the combined effects of ion dynamics and opacity on line profiles used in the analysis of these plasmas. The experiments discussed were performed at the University of Rochester Laboratory for Laser Energetics (LLE). The results presented in this paper illustrate the usefulness of plasma line broadening in diagnosing hot dense plasmas and in understanding fundamental plasma processes.

We propose a model for calculating free-free absorption (inverse bremsstrahlung) in hot dense plasmas. This model writes the total Gaunt factor as the product of a static factor and a dynamic factor. The treatment of the static part is based on a relation between the absorption cross section and the elastic scattering cross section, which is exact for very low frequencies and becomes asymptotically correct when the Born approximation is valid. Generalizing this relation provides an expression of the absorption cross section Q(k, k′), which depends on the initial and final wave vectors k and k′, as an integral of a unique function S*(k). The calculation of nondiagonal matrix elements (k ≠ k′) is thus avoided. The analytic summation of the high angular momenta in the partial wave expansion of the cross section makes possible to apply the model in the limit of weak electron screening. The collective effects are accounted for in a dynamic Gaunt factor and in an index of refraction different from unity. Numerical results for the Gaunt factor in cesium are presented and discussed. An application to the mean opacities of carbon is also shown.

We reconsider correlated ion stopping in plasmas with the aim to emphasize the basic features and their underlying physics. For a better understanding of the effects connected with correlated ion stopping, it is useful to distinguish two types of correlated ion stopping, characterized by a small or large ratio of the correlation length of the ions to the screening length in the plasma. These two types of correlated ion stopping are of rather different character. We describe and explain these differences and give some generic examples of ion structures and ion clusters to demonstrate the basic features of both types of correlated stopping. This shows that only the short-range correlations always yield an enhanced stopping, whereas the long-range correlations, in general, reduce the stopping compared to single, individual ions. We mainly consider classical plasmas; the basic features, however, remain unchanged for a jellium target as well as for a plasma at any degeneracy.

The possibility of using the analytical wave functions in hydrogen-like and semiclassical approximations for self-consistent Hartree-Fock-Slater model is considered. The usage of analytical wave functions simplifies the obtaining of self-consistent field and yields the suitable expressions for calculation various characteristics of high-temperature plasmas—cross sections of radiative processes, Rosseland mean opacities, and equation of state.

Due to the high nonequilibrium charge states specific to heavy ions, the plasma regime with coupling parameters l/ND < 1 and Zp/ND > 1 (ND ∼ number of electrons in a Debye sphere, Zp mean charge state of the projectile) is of interest for the applications. In this regime the stopping power cannot be obtained by a linearization of the Vlasov-Poisson system, but forcing a fully nonlinear treatment. In the present paper the Vlasov-Poisson system is solved numerically by using the capability of the new generation of massively parallel supercomputers. The results are compared with the standard dielectric theory and a binary collision approach. Charge-state calculations are performed, accounting for all relevant features of the atomic processes and the spectra characteristic to heavy ions in dense plasma targets. The results show good agreement with experimental measurement for medium and heavy ions penetrating a Z-pinch device.

The behavior of matter under intense soft X-radiation is considered. An impulse of X-radiation (about 2–1012 W/cm2) produced a strong shock wave in the sample. The velocity of this shock wave was measured. A shock compression about 300 GPa in the lead target was achieved.