Historical research guide · 1065 · 2001
Transient electrical discharges in small devices
Leopoldo Soto · Andrey Esaulov · José Moreno · Patricio Silva · Gustavo Sylvester · Marcelo Zambra · Andrey Nazarenko · Alejandro Clausse
In one minute
Big plasma machines cost what a building costs. Leopoldo Soto and his colleagues at the Chilean Nuclear Energy Commission, working with Andrey Esaulov, Andrey Nazarenko and Alejandro Clausse, make the case that you do not always need one. Plasmas at high energy density — the unstable, radiating kind that fusion and X-ray work care about — can be produced in small pinch devices at relatively low cost, and this paper walks through three of them. A capillary discharge, where the current is forced through a narrow bore. A Z-pinch driven by a small generator, where the current squeezes its own column. And a low-energy plasma focus, where a sheet of current runs down two coaxial electrodes and collapses onto the axis. Each was built alongside magnetohydrodynamic calculations that both guided the design and made sense of the data, and each was watched with a full diagnostic kit: current and voltage monitors, a multipinhole camera, holographic interferometry and vacuum ultraviolet spectroscopy.
Connection
This is the programme paper behind the small-device work chapter 9 keeps returning to — the statement, in 2001, that dense unstable radiating plasma is a bench subject and not only a national-laboratory subject. Chapter 12 cares for the same reason: everything downstream on this site waits on a compact high-density source, and a compact source has to be built and diagnosed by somebody first.
From the source
Fundamental and applied research on plasmas with high energy density that are unstable and radiate can be carried out at relatively low cost with small plasma pinches.Abstract, sentence 1
The paper treats three small pinch devices as one subject: a capillary discharge, a Z-pinch driven by a small generator, and a low energy plasma focus.Abstract, sentence 2
The experiments were complemented by magnetohydrodynamic numerical calculations, used both to assist the design of the devices and to interpret the experimental data physically — so the modelling is part of the instrument, not a commentary added afterwards.Abstract, sentence 3
The diagnostics used across the three experiments were current and voltage monitors, a multipinhole camera, holographic interferometry, and vacuum ultraviolet spectroscopy — that is, the electrical drive, the spatial structure of the emission, the electron density and the spectrum were all recorded on the same small machines.Abstract, sentence 4
What to watch: the open question this survey sets up is how far down the scale the physics survives — whether the dynamics, pinch conditions and electron densities of large pinch machines are still reached when the stored energy falls to hundreds and then tens of joules. The same Santiago laboratory answered it experimentally over the following decade, first at a few hundred joules and then at tens.Abstract, read against the group’s later hundreds-of-joules and tens-of-joules results
The way in
https://doi.org/10.1063/1.1351829How to cite it
Leopoldo Soto, Andrey Esaulov, José Moreno, Patricio Silva, Gustavo Sylvester, Marcelo Zambra, Andrey Nazarenko, Alejandro Clausse (2001) Transient electrical discharges in small devices doi:10.1063/1.1351829