Four years after the initial proposal of the Plasma Wake-field Accelerator (PWFA), it continues to be the object of much investigation, due to the promise of the ultra-high accelerating gradients that can exist in relativistic plasma waves driven in the wake of charged particle beams. These wake-fields are of interest both in the laboratory, for acceleration and focusing of electrons and positrons in future linear colliders, and in nature as a possible cosmic ray acceleration mechanism. The purpose of the present work is to review the recent experimental advances made in PWFA research at Argonne National Laboratory. Some of the topics discussed are: the Argonne Advanced Accelerator Test Facility; linear plasma wake-field theory; measurement of linear plasma wake-fields; review of nonlinear plasma wave theory; and experimental measurement of nonlinear plasma wake-fields. 25 refs., 11 figs.

Magnetic switching is a pulse compression technique that uses a saturable inductor (reactor) to pass pulses of energy between two capacitors. A high degree of pulse compression can be achieved in a network when several of these simple, magnetically switched circuits are connected in series. Individual inductors are designed to saturate in cascade as a pulse moves along the network. The technique is particularly useful when a single-pulse network must be very reliable or when a multi-pulse network must operate at a high pulse repetition frequency (PRF). Today, magnetic switches trigger spark gaps, sharpen the risetimes of high energy pulses, power large lasers, and drive high PRF linear induction accelerators. This paper will describe the technique of magnetic pulse compression using simple networks and design equations. A brief review of modern magnetic materials and of their role in magnetic switch design will be presented. 12 refs., 8 figs.

Concrete barriers are an important component of many designs for disposal of radioactive waste in the unsaturated zone. In order to evaluate the effectiveness of the concrete barriers performance assessment models representing the material degradation rates and transport properties must be developed. Models for evaluation of fluid flow and mass transport through partially failed concrete barriers located in the unsaturated zone are presented. Implications of the use of impermeable barriers design are discussed. Concrete of highest quality may not always be desirable for use in all components of waste disposal vaults. 7 refs., 5 figs.

An approach has been formulated to route nuclear spent fuel over the US Interstate highway network. This approach involves the generation of alternative routes so that any potential adverse impacts will not only concentrate on regions along the shortest path between the nuclear power plant and repository. Extensive literature research on the shortest path finding algorithms has been carried out. Consequently, an extremely efficient shortest path algorithm has been implemented and significantly increases the overall system performance. State-of-the-art interactive computer graphics is used. In addition to easy-to-use pop-up menus, full color mapping and display capabilities are also incorporated. All of these features have been implemented on commonly available personal computers. 6 figs., 2 tabs.

Monopole, dipole and quadrupole wake potentials are calculated for two cavities in a standing-wave relativistic klystron, using two independent programs, TBCI and AMOS. Reflections from model terminations which may distort long-range wakes can be mitigated either by using a very long pipe or by using absorptive materials at the pipe boundaries. 7 refs., 10 figs.

A shell model approach leads to a simple constituent quark model for hadron structure in which mesons and baryons consist only of constituent quarks. Hadron masses are the sums of the constituent quark effective masses and a hyperfine interaction inversely proportional to the product of these same masses. Hadron masses and magnetic moments are related by the assumption that the same effective mass parameter appears in the additive mass term, the hyperfine interaction, and the quark magnetic moment, both in mesons and baryons. The analysis pinpoints the physical assumptions needed for each relation and gives two new mass relations. Application to weak decays and recent polarized EMC data confirms conclusions previously obtained that the current quark contribution to the spin structure of the proton vanishes, but without need for the questionable assumption of SU(3) symmetry relating hyperon decays and proton structure. SU(3) symmetry breaking is clarified. 24 refs.

The power supply working group was assigned the problem of pulse charging the 3-MeV gun. The gun is a radial line structure that has two charging configurations: a single ring charged to 500 kV or nine rings charged from 100 to 200 kV. In either configuration, the pulsed source must rapidly charge the structure's ring(s) before breakdown can begin. The issues encountered in charging the structure can be divided into two categories. First, the charging system must be well matched to the gun structure. Proper impedance matching will avoid reflections and limit the fault current if the ring should spark. Second, several systems can achieve the wide range of charge voltages necessary. Some are better suited to high voltages, while others are better at low voltages. The following paragraphs will address the impedance matching issues and review three choices for pulse generators. A system for each type of source is described along with a very rough cost estimate. 1 ref., 4 figs., 2 tabs.