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Seventh Harmonic 20 GHz Co-Generator--Omega-P, Inc., 345 Whitney Avenue, Suite 100, New Haven, CT 06511; 203-458-1144
Dr. Jay L. Hirshfield, Principal Investigator
Mr. George P. Trahan, Business Official
DOE Grant No. DE-FG02-98ER82632
Amount: $600,000
High-power rf amplifiers are required at frequencies above 11.4 GHz for a future multi-TeV electron/positron collider. The use of efficient harmonic conversion, such as in a co-generator, would allow existing rf sources and components to be used to satisfy this need. In this project, a co-generator to generate efficient 7th harmonic power at 20GHz will be designed, built, and evaluated. Theory and tests conducted during Phase 1 indicate that direct conversion efficiencies exceeding 50 percent are possible, and that the overall device efficiency can be raised to 85 percent by recovering the spent beam energy using a depressed collector. Computations showed that the new co-generator configuration would allow high-efficiency transfer of 2.856 GHz drive power to an injected electron beam, prevent drive power from propagating in the output section, and allow a small amount of 20GHz power to be generated and injected at the input of the output section. Preliminary experiments using a more primative structure showed strong 7th harmonic output at 20 GHz. Phase II will complete the engineering design and fabricate an improved co-generator to produce multi-megawatt 7th harmonic output at 20 GHz. The theory will be extended to a multi-mode, coupled-segment structure and both beam optics and magnetic field profile will be optimized for high efficiency conversion. Laboratory evaluations of the 20 GHz co-generator will be performed and results will be scaled to a device with 80 GHz output, using 60 MW of 11.424 GHz drive power.
Commercial Applications and other Benefits as described by the awardee: The rf source selected for a future electron/positron collider will have to be supplied in quantities of thousands. A major advantage of a co-generator is that it uses existing lower-frequency sources and components, with substantial cost savings. The market for co-generators for a future TeV-collider could be several hundred million dollars.