Development of circuit models for extractor components in high power microwave sources

Summary form only given. The state-of-the-art in high power microwave (HPM) sources has greatly improved in recent years, in part due to advances in the computational tools available to analyze such devices. Chief among these advances is the widespread use of parallel particle-in-cell (PIC) techniques. Parallel PIC software allows high fidelity, three-dimensional, electromagnetic simulations of these complex devices to be performed. Despite these advances, however, parallel PIC software could be greatly supplemented by fast-running parametric codes specifically designed to mimic the behavior of the source in question. These tools can then be used to develop zero-order point designs for eventual assessment via full PIC simulation. One promising technique for these parametric formulations is circuit models, where in the full field description is reduced to capacitances, inductances, and resistances that can be quickly solved to yield small signal growth rates, resonant frequencies, quality factors, and potentially efficiencies. Building on the extensive literature from the vacuum electronics community, this poster will investigate the circuit models associated with the purely electromagnetic components of the extractor in the absence of space charge. Specifically, three-dimensional time-domain computational electromagnetics (AFRL's ICEPIC software) will be used to investigate the modification of the resonant frequencies and mode quality factors as a function of slot and load geometry. These field calculations will be reduced to circuit parameters for potential inclusion in parametric models, and the fidelity of the resulting description will be assessed