Diocotron instability for relativistic non-neutral electron flow in planar magnetron geometry

Journal Article · Thu Oct 01 00:00:00 EDT 1992 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860395· OSTI ID:7250440

Ayres, V M; Chen, H C; Stark, R A; Uhm, H S ^[1]; Brandt, H E ^[2]

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1. Naval Surface Warfare Center, White Oak Laboratory, Silver Spring, Maryland 20903 (United States)
2. Harry Diamond Laboratories, Adelphi, Maryland 20783 (United States)

Diocotron stability properties of relativistic non-neutral electron flow in a planar magnetron are investigated within the framework of the cold-fluid-Maxwell equations. The eigenvalue equation for the extraordinary-mode waves in a relativistic velocity-sheared electron layer is obtained, and is solved in the massless, guiding-center approximation. Approximating the electromagnetic field in the anode resonator by the lowest-order mode, the dispersion relation for the diocotron instability is obtained. Although the tenuous beam approximation is assumed, the eigenvalue equation and corresponding dispersion relation are both fully electromagnetic, and valid for relativistic electron flow. The dispersion relation is numerically investigated for a broad range of system parameters. From numerical calculations of the dispersion relation, it is shown that the typical growth rate of the diocotron instability indicates a strong instability. The early evolution of the diocotron instability as an important precursor to the evolution of the full magnetron oscillation is discussed.

• OSTI ID: 7250440
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 4:10; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
DIFFERENTIAL EQUATIONS
DISPERSION RELATIONS
EIGENVALUES
ELECTROMAGNETIC RADIATION
ELECTRON TUBES
ELECTRONIC EQUIPMENT
ENERGY RANGE
EQUATIONS
EQUIPMENT
GUIDING-CENTER APPROXIMATION
INSTABILITY
MAGNETRONS
MAXWELL EQUATIONS
MICROWAVE EQUIPMENT
MICROWAVE RADIATION
MICROWAVE TUBES
PARTIAL DIFFERENTIAL EQUATIONS
PLASMA INSTABILITY
RADIATIONS
RELATIVISTIC RANGE
RESONATORS