The heating of plasma focus electrodes
E. Angeli · M. Frignani · S. Mannucci · F. Rocchi · M. Sumini · A. Tartari
Summary and citation · read the original at the source
In one page
A plasma focus is a beautifully simple machine: dump a capacitor bank into two coaxial electrodes, and the current sheet that sweeps down the barrel collapses onto the axis and pinches a knot of plasma hot enough to fuse deuterium. Firing it once is easy. Firing it many times a second — which is what any practical neutron source or fusion device would have to do — runs into a plainer problem, and this paper measures it. Angeli, Frignani, Mannucci, Rocchi, Sumini and Tartari, working between the universities of Ferrara and Bologna, watched the inner electrode of a Mather-type machine cool after shots at several different bank energies, compared the decay curves against theoretical and numerical models, and extracted two candidate scaling laws linking the heat deposited to the energy stored. Their headline number is the one a designer needs: roughly a tenth of the total energy in the bank ends up in the inner electrode. They close by asking what temperature the electrode materials can actually stand.
Why it matters hereChapter 9’s plasma focus is the cheapest laboratory route to a dense, self-organising, fusion-relevant plasma, and chapter 12 cares whether such a machine can run continuously rather than once. This paper supplies the engineering constraint that decides it: how much of every shot lands as heat on the hardware, and how hot the hardware is allowed to get.
What it claims
01Plasma focus technology development today is strictly related to the possibility of a high-frequency repetitive working regime, and one of the more relevant obstacles to that goal is the heating of structural components by their direct interaction with the plasma.Abstract, sentences 1 and 2; Plasma Sources Science and Technology 15, 91 (2006)
Published and peer-reviewed02The measurement reported is the temperature decay of the inner electrode of a Mather-type plasma focus, taken over several series of shots at different capacitor-bank energies.Abstract, sentences 3 and 4
Published and peer-reviewed03The experimental data are analysed against theoretical and numerical models of the heating, so the result is a comparison rather than a bare measurement.Abstract, sentence 4
Published and peer-reviewed04Two possible scaling laws are derived from the experimental data, each correlating the thermal deposition on the electrode with the energy stored in the bank.Abstract, sentence 5
Published and peer-reviewed05A fraction of about ten per cent of the total energy is released to the inner electrode.Abstract, sentence 6
Published and peer-reviewed06What to watch: after setting out the cooling and heating mechanisms the authors analyse the maximum temperature the electrode materials can sustain, which turns the ten per cent figure into the design question for a repetitive machine — how fast heat can be pulled back out of the inner electrode between shots. The number to watch in this line of work is the sustained repetition rate a cooled electrode survives at a given bank energy.Abstract, final sentence, read against sentences 1 and 6
What to watch
The way in
https://doi.org/10.1088/0963-0252/15/1/014SOURCE NOT REACHED IN FULL. IOP holds the article closed; Unpaywall and OpenAlex both report no open version anywhere, and on 2026-09-08 the IOPscience article page answered with a Radware bot-manager challenge rather than the article, while the Bologna and Ferrara institutional repositories served their web front end instead of their record API. No text of the article is reproduced here. The summary and the claims are written from the authors’ own abstract as deposited with the article and indexed by OpenAlex, and from the Crossref record, which fixes the venue as Plasma Sources Science and Technology volume 15, issue 1, pages 91 to 98, 1 February 2006. Locators therefore point to sentences of the abstract rather than to numbered sections. One descriptor is left as the indexed abstract prints it: the device is called ’a 7 U Mather type PF’, and the unit abbreviation is not expanded here because no reachable record confirms it. OpenAlex places Angeli and Tartari at the University of Ferrara and Frignani, Mannucci, Rocchi and Sumini at the University of Bologna; initials are given as Crossref records them.
How to cite it
E. Angeli, M. Frignani, S. Mannucci, F. Rocchi, M. Sumini, A. Tartari (2006) The heating of plasma focus electrodes. doi:10.1088/0963-0252/15/1/014
Where it sits in the curriculum
Plasmoids, charge clusters and the orbsLattice confinement fusion