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This Defense Intelligence Agency reference document, dated 10 March 2010, covers inertial electrostatic confinement (IEC) fusion. It was produced in FY 2009 under the DIA's Advanced Aerospace Weapon System Applications (AAWSA) program. The report focuses on work at the University of Illinois Urbana-Champaign and reviews IEC basics, experiments, theory and applications such as neutron sources, explosives detection and space propulsion. It concludes by proposing a breakeven experiment for p-11B fusion that uses a hydrogen plasma simulation.
UNCLASSIFIED/;«F&A 8FFlil.l1k WE&i &•lk¥ Bussard HEPS (or Polywell) Concept In Bussard's Polywell IEC, a spherical magnetic field termed a "Polywell" is approximately obtained with a multi-pole cusp magnetic field (Reference 1.6). More about the theory of flows in this configuration is given in the paper by N. Krall (Reference 1.7), and some stability issues are addressed in the Wang and Krall paper of Reference 1.8. One of the key physics revolves around electron losses from the poles in the cusp field. Krall and Bussard argue that a plasma "waffle-ball" effect causes the loss cone angle to be reduced due to the high pressure developed in the IEC plasma. The issue still needs further experimental verification. The Polywell approach is very important and it is currently pursued by R. Nebel's EMC2 company in Santa Fe with significant DOD funding. More insights will be provided throughout this report, but the reader is encouraged to study the reports/articles, as already explained earlier, since the present report is directed more at "ion injected" type devices studies at UIUC. Barnes Nebel Penning Trap The Penning trap concept described in Reference 1.9 is explained by Barnes et al. as: "The Penning Fusion (PF) device uses a unique plasma confinement principle. In PF, a nonneutral electron plasma is confined in a modified Penning trap by a combination of applied magnetostatic and electrostatic fields. The electron space charge, in turn, electrostatically confines a minority, unmagnetized ion species. To apply such a system to fusion energy production, it is necessary to raise the applied voltages (producing the confining electrostatic field) to the order of 100 kV or greater. Even with such a high potential, in a practically sized system, the electron density (and to a greater degree the ion density) falls short of that required to give reasonable fusion reactivity. Thus, intrinsic to PF being an interesting concept is the idea of ion focusing, either in space or time, or some other means of enhancing ion reactivity. In this way the reactivity may be greatly enhanced over that available with the background density. Penning Fusion is strongly related to the IEC, but it attempts to address two limitations of the IEC. First, following the Bussard-Krall Polywell theory (Reference 1.6, 1.7) the grid is replaced by an electron cloud, which forms a virtual cathode. In this way, ion-grid collisions and associated limitations (such as secondary electron emission from the grid and grid heating) are avoided. Second, high rates of ion-ion collisions, which limit the theoretically achievable fusion gain Q (fusion power/input power) to around unity are avoided to some extent with this type of well. However, issues of electron loss and cone losses, radiation damage of the magnets and cooling, and the ability to circumvent the Elmore et al. density limit remain as questions. Nebel POPS Device Theoretical studies by Barnes and Nebel (Reference 1.10) show that a small internal oscillating ion cloud may undergo a self-similar collapse in a harmonic oscillator potential formed by a uniform electron background. This then forms a dynamic IEC device, but with a quite different ion distribution factor vs. the "conventional" beam-like one. A key issue for this concept is how much plasma compression can be achieved by the POPS (Periodically Oscillating Plasma Sphere) oscillations. Recent work has shown that by properly programming the distribution function of the injected electrons it is possible to significantly improve the space dynamic charge neutralization and the plasma compression. Reference 1.10 extends that previous work in a systematic fashion by developing a formalism that determines the required velocity distribution of 10 UNCLASSIFIED/ ;CEiOAt OFFiiI.«1k W&li &••tv
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Report, from the dia collection. The PDF is mirrored here; the original link is above. 72 pages are in the text index: search them above, or from the library's search.