Historical research guide · 0457 · 1976
Application of the relativistic electron beams originating in the discharges of plasma focus type for the combined laser-REB plasma heating
V. A. Gribkov
In one minute
In 1976 Vitaliy Gribkov brought a short paper to an international meeting in Turin on how to store energy and then let it go fast. His subject is a by-product most people treated as a nuisance. A plasma focus is a capacitor bank dumped in microseconds into a gas: the current sheet runs down a coaxial gun, sweeps the gas ahead of it, and collapses into a tiny, dense, extremely hot pinch. At the moment of collapse the machine also fires out a beam of electrons travelling near the speed of light, back along the axis. Gribkov’s proposal, stated in his title, is to stop treating that beam as waste and start using it — to heat plasma with the relativistic electron beam and a laser together rather than with either alone. The paper sits with the fast-discharge work in that volume, which is the right home for it: the plasma focus is among the simplest machines ever built for turning slowly stored energy into a brief, self-organising plasma.
Connection
Chapter 9 is about self-organising plasma structures, and the plasma focus is the laboratory case where one forms on demand and throws out its own particle beams. Chapter 12 is about driving nuclei together by engineering their environment rather than by brute confinement, and this chapter is an early instance of the same instinct — use the machine’s own self-generated beam as one of the drivers.
From the source
A plasma focus discharge originates relativistic electron beams. Gribkov’s title states it as an established fact of the device and builds on it: when the current sheet of a plasma focus collapses onto the axis, the machine emits not only radiation and an ion beam directed away from the anode but an electron beam driven back into it, with electron energies reaching relativistic values. That the beams exist, and that they come out of the collapse itself rather than from any separate accelerator, is the premise the whole chapter rests on.Title, chapter 31, pages 271 to 276
The proposal is combined heating. Rather than choose between a laser and a particle beam, Gribkov’s title puts the plasma focus’s own relativistic electron beam and a laser onto the same plasma, for what he calls combined laser-REB plasma heating. The interest of that is architectural: the beam is free, in the sense that the discharge makes it anyway, so a machine already built to compress plasma also supplies one of the two heating channels.Title, chapter 31, pages 271 to 276
The venue places the work correctly. Energy Storage, Compression, and Switching gathers, in the editors’ own scope, slow systems such as mains-frequency machinery, transformers and flywheel-homopolar generators, intermediate systems such as fast capacitor banks and superconducting storage, and fast systems — Marx and Blumlein generators, oil, water and pressurised-water dielectrics, magnetic insulation, electron beams and plasmas. Gribkov’s chapter belongs to the last group, which is where a plasma focus belongs: it is an energy-compression device first and a plasma experiment second.The volume’s published scope, Energy Storage, Compression, and Switching, Plenum Press 1976
This is the opening of a long programme, not an isolated note. Gribkov went on to spend decades measuring what a dense plasma focus actually emits and what those emissions do — the hot plasma and fast ion streams, their interaction with materials under test, and the pinch dynamics of megajoule-class devices — and that later work is published, refereed and available. The 1976 chapter is where the idea of putting the machine’s own beams to work first appears under his name.Author line; continued in his 2015 Plasma Physics and Controlled Fusion paper on dense plasma focus devices
What to watch: whether a plasma focus can be driven to useful net fusion output using its own self-generated beams as part of the drive. The measurements that would settle it are being taken on the modern descendants of Gribkov’s machines — the megajoule PF-1000 class devices, where pinch dynamics and beam production are now diagnosed shot by shot — and in the aneutronic proton-boron work that uses the same geometry. The 1976 chapter itself remains hard to check: the volume has not been digitised, so the argument behind the title has to be read on paper.Title; and the record, which shows one citing work and no digitised copy
The way in
https://doi.org/10.1007/978-1-4684-2214-6_31How to cite it
V. A. Gribkov (1976) Application of the relativistic electron beams originating in the discharges of plasma focus type for the combined laser-REB plasma heating doi:10.1007/978-1-4684-2214-6_31