Summary form only given, as follows. DECFA and DEMAG are movingwavelength, particle in cell codes for modeling crossed-field amplifiers(CFAs) and magnetrons. These codes are based on prior efforts of Yu,Koogers and Buneman in 1965. The codes model the interaction between asingle traveling wave on a smooth anode surface and the space charge incrossed electric and magnetic fields. The detailed anode vane tipgeometry is not included in the model. Periodic boundary conditions areimposed on the sides of the moving interaction wavelength therebyimposing the wave periodicity on the solution. The effect ofdisturbances in the space charge at other wavelengths is not considered.In spite of the assumptions involved, the codes successfully model theperformance of many existing CFAs and magnetrons. Correlation ofcomputer model and experimental results will be presented for typicaldevices. The only failures of the codes to correlate with deviceperformance have occurred for small gap anode vane tip geometries whichdegrade the efficiency of electron collection. To avoid suchpossibilities, the simulation codes need to be supplemented withtrajectory tracing studies of electrons between anode vanes. Results ofsuch studies will be presented. Through their diagnostics, the codesprovide a means of studying the details of the crossed-fieldinteraction. Of particular current interest are time fluctuations ofsome of these diagnostics. These fluctuations appear to be chaotic innature. They develop in the absence of any random inputs but remainbounded in magnitude. The amount of thermionic and secondary emission,are found to have a major effect on these fluctuations. These resultsare expected to contribute to the understanding of noise mechanisms incrossed-field devices
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