Under the stimulus of electronic materials development - particularly thin-film studies - and the need for space environmental simulation chambers, a very rapid increase in the availability of industrial-sized vacuum components and systems operable in the ultrahigh vacuum range has taken place in the last three years. It is the purpose of this paper to explore the design considerations of ultrahigh vacuum systems for metallurgical applications.

Nuclear excavation is the name given to the concept of using large scale nuclear explosion craters for useful projects, such as harbors, canals, and roadway cuts. It is one of the principal applications of the Plowshare Program for industrial, or peaceful, uses of nuclear explosives. Plowshare is sponsored by the U.S. Atomic Energy Commission and is under the technical direction of the Lawrence Radiation Laboratory at Livermore, California. The purpose of this paper is to describe cratering concepts and the present state of nuclear excavation technology. The general nature of the safety hazards associated with nuclear excavation are also discussed.

This paper reports an extension of previous experimental work with Alfven waves. We consider hydromagnetic waves propagating in a cylindrical plasma in a uniform axial magnetic field. The copper tube is filled with highly ionized plasma by an electrically driven switch-on ionizing wave. After the tube is filled with plasma, a hydromagnetic wave is induced by a radial current flow from the small molybdenum electrode to the copper tube. The force produced by this radial current together with the static axial magnetic field displaces the plasma in the azimuthal direction, and a transverse wave is propagated in the axial direction, along magnetic field lines. The transient magnetic field associated with the wave is also in the azimuthal direction.

The computer program which performs spatial reconstruction of events photographed in a bubble chamber is required to eliminate human and digitizer errors. It recognizes and corrects for single nuclear scatterings in the presence of multiple Coulomb scatterings. Momentum components are determined and kinematic constraints are applied. Measured parameters are performed into special reference frames and quantities of physical interest are calculated. Results are stored in a tape file containing all events of one reaction type.