Reentrant 500 k V Connection for Inverted Sheet Beam Klystron

75414-The klystron group at Stanford Linear Accelerator Center (SLAC) is developing a gridded, sheet beam klystron that produces fast rise and fall time 400 ns RF pulses. The geometry of the present design encloses the klystron gun and the tube vacuum in a very large and expensive ceramic enclosure so that the gun can withstand the very high DC voltage. Eliminating the enclosure through a reentrant connection would result in a design that is much smaller, lower in cost, and easier to manufacture. This project involves the design and construction of a new connection between the cable and the klystron, which complements the tube geometry under consideration by SLAC. In this design, the cathode/grid structure is reentrant into the tube housing, with the grid/heater connection at the bottom of an oil-filled housing that is part of the tube structure. This approach eliminates the expensive large-diameter ceramic of the existing tube design because the klystron gun ceramic is much smaller in diameter and acts directly as the cable socket. Phase I will focus on the design of the reentrant sheet beam klystron connection and vacuum insulator. Tasks include a requirements definition, electrostatic and mechanical stress analysis using electromagnetic modeling software, materials definition, and diagnostics and testing specification. The design effort will be conducted in close cooperation with SLAC to ensure that it is consistent with related efforts to build the sheet beam klystron. Commercial Applications and Other Benefits as described by the awardee: The primary benefit should be a large reduction in the manufacturing costs of components for the Next Generation Linear Collider. Once this high voltage, reentrant connection has been developed and proven for the NLC, thousands of industrial and medical accelerators would also be targets for adopting the sheetbeam klystron technology. In these accelerators, the cable socket technology would be required to transition these systems from conventional klystrons to the new technology.