Electron flow stability in magnetically insulated vacuum transmission lines

Journal Article · Tue Mar 15 04:00:00 EDT 2011 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3567016· OSTI ID:21537319

Rose, D V; Genoni, T C; Clark, R E; Welch, D R ^[1]; Stygar, W A ^[2]

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1. Voss Scientific, LLC, Albuquerque, New Mexico 87108 (United States)
2. Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

We evaluate the stability of electron current flow in high-power magnetically insulated transmission lines (MITLs). A detailed model of electron flow in cross-field gaps yields a dispersion relation for electromagnetic (EM) transverse magnetic waves [R. C. Davidson et al., Phys. Fluids 27, 2332 (1984)] which is solved numerically to obtain growth rates for unstable modes in various sheath profiles. These results are compared with two-dimensional (2D) EM particle-in-cell (PIC) simulations of electron flow in high-power MITLs. We find that the macroscopic properties (charge and current densities and self-fields) of the equilibrium profiles observed in the simulations are well represented by the laminar-flow model of Davidson et al. Idealized simulations of sheared flow in electron sheaths yield growth rates for both long (diocotron) and short (magnetron) wavelength instabilities that are in good agreement with the dispersion analysis. We conclude that electron sheaths that evolve self-consistently from space-charged-limited emission of electrons from the cathode in well-resolved 2D EM PIC simulations form stable profiles.

• OSTI ID: 21537319
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 3 Vol. 18; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CURRENT DENSITY
DISPERSION RELATIONS
ELECTRON EMISSION
ELECTRONS
ELEMENTARY PARTICLES
EMISSION
FERMIONS
FLUID FLOW
INSTABILITY
LAMINAR FLOW
LEPTONS
PLASMA INSTABILITY
PLASMA SIMULATION
SIMULATION
SPACE CHARGE
STABILITY
TWO-DIMENSIONAL CALCULATIONS