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Three concepts of an rf gun to be operated at 0.1-10 mm wavelengths are considered. In all the concepts, the rf system exploits an accelerating traveling wave. In comparison with a classical decimeter standing-wave rf gun, we analyze the advantages of new concepts, available rf sources, and achievable beam parameters. [ABSTRACT FROM AUTHOR]

Multi-mode accelerating structures aimed at increasing accelerating gradient are described. Such structures operating in several resonant, equidistantly-spaced, axisymmetric, TM-like eigenmodes allow reduction of exposure time to surface fields, reduction of high-field areas and reduction of those fields which are responsible for electron emission. These effects are planned for use in studying the physics of RF breakdown phenomenon with the goal of designing new high-gradient accelerating structures. [ABSTRACT FROM AUTHOR]

A multi-harmonic asymmetric cavity is predicted to sustain higher acceleration gradients than a conventional pillbox cavity, 55% higher in one example, when driven by external RF harmonic sources. Simulations of multi-harmonic excitation in such a cavity are described, either by a charged drive beam or by external RF sources. An accelerator structure based on multi-harmonic cavity is proposed. [ABSTRACT FROM AUTHOR]

A two-beam accelerator structure is described having several novel features including all metal construction, no transfer structures required between the drive and accelerator channels, symmetric fields at the axes of each channel, RF micropulse widths on cavity irises that are less than half those for a conventional cavity at the same fundamental frequency by virtue of using several harmonically-related cavity modes, and a transformer ratio much greater than unity by the use of detuned cavities. Detuning is also shown to allow either parallel or anti-parallel directions for the drive and accelerated beams. A preliminary calculation for the dilution of emittance due to short-range wakes for drive beam parameters similar to those for CLIC shows this effect to be acceptably small. [ABSTRACT FROM AUTHOR]

Summarized results obtained in several experiments on active RF pulse compression at X-band using the Omega-P/NRL magnicon are presented. In these experiments RF energy is stored in two parallel-fed resonators and then discharged using switches activated with rapidly-fired plasma discharge tubes. New results with both transmission and reflection switches are reported, with peak power gains in the range of 8–10. The application of developed plasma switches for an electrically controlled switching of an existing passive pulse compressor SLEDII for increasing its efficiency is discussed. The low-power test of the plasma switch with a 35 m SLEDII delay line is described. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The concept of a planar Lower Hybrid (LH) wave guide using resonant power division in slotted waveguide, and featuring potential desirable features, such as a simpler construction, less obtrusive dimensions and weight, adaptive matching, and eide range N// modulation capability is presented. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]