In a recent review of high power density systems, the "Z" pinch work done by Sandians in New Mexico was described. These folks have made a huge amount of progress, adapting as they go along and learning to make small devices that surely rival the work done at NIF in California on the road to Fusion in the lab.

The "Z"-pinch machine that they are now upgrading started out as a light ion device, PBFA, and during the experimental campaign it was learned that the light ion approach would be less useful, and that the machine could do some amazing tricks useful in their own right using the basic setup, forgetting the light ions and using the driver alone.

Scientists learned to produce an incredibly bright X-ray source by zapping a ring of tiny wires with a huge current. This donut of wires is vaporized in an instant forming a plasma donut that collapses on itself. The resulting flash is as bright as a nuclear weapon's X-ray pulse and thus useful for lab studies, and practical effects testing. The huge magnetic fields generated by the plasma and it's subsequent collapse are also useful in their own right.

Sandia has driven a tiny flyer plate to over 30Km/Sec, which would be faster than escape velocity from earth ( ignoring aerodynamic effects that would tear the plate up if launched in air at the ground.....) for use in material property testing experiments. Sandia scientists have been able to tailor the acceleration so that the material stays intact long enough to do experiments on the properties of various materials at a high degree of pressure.

The X-rays generated by the Z process can be harnessed in a tiny gold cylinder configured as a hohlraum, a cavity where the surfaces are heated by the X-rays, and surround a capsule target that may contain fusion fuel such as deuterium. The uniform bath of X-rays evaporates the surface of the capsule and the ablated material rockets the remaining material into a pinpoint of highly compressed material.

Utilizing the pettawatt laser technology developed at Lawrence Livermore Labs, the "Z" machine will be able to zap the compressed pellets with a "spark" that may ignite fusion, producing the elusive "star in the lab".

While I appreciate the many tricky physics issues remaining, it's clear that the progress made since 1995 is huge, and that the program could produce a working device soon if supported with a sufficient budget and staffed with enough bright scientists and engineers. This program should be pushed and supported by our government, indeed by the world community and not forced to compete with magnetic fusion and laser fusion programs, simply on the merits of the case, and because it is too soon to tell which approach will be the most useful.

I think that given the geopolitical situation, it is wise for a nation to persue the sort of energy system that could free us from dependency on oil, that could power our flight to the planets, that could help us to understand the high energy densityphysics.

These exciting developments are mostly shielded from public view behind a secret curtain, parted now and then as either scientific developments are published ( thanks to the American Instutite of Physics), or as the developers seek funding. The military applications are driving the funding at this point, though I believe that our nation would benefit from a much broader and better financed program. There are certainly proliferation concerns, but it's a very technically difficult process and unlikely to be attractive to the sort of folks who want instant political power so any concerns are way down the line from a practical point of view.

The Bush administration should immediately increase support for this area of research, broadening the work from NRL and Sandia to include various university programs, and to train the next generation of scientists, engineers, and technicians in this vital area.