Pulse Power Switch Development; Final Report for period 19 September 1979 through 18 January 1980

66 pages. Illustrations. References. Unclassified. Approved for public release. Distribution unlimited. Number 25 stamped on front cover. HRL Laboratories (formerly Hughes Research Laboratories), was the research arm of Hughes Aircraft. It is a dedicated research center, established in 1960, in Malibu. In the 1940s, Howard Hughes created a R&D facility in Culver City, California; by 1960, it moved to Malibu, California. General Motors purchased Hughes Aircraft in 1985. GM sold the Hughes aerospace and defense operations to Raytheon in 1997, and spun off Hughes Research Laboratories (legally renamed "HRL Laboratories, LLC"), with GM and Raytheon as co-owners. GM sold the Hughes satellite operations to Boeing in 2000, and the co-owners became Boeing, GM, and Raytheon. In 2007, Raytheon decided to sell its stake, though it still maintains research and contractual relations with HRL. For more details, please see Hughes Aircraft. HRL receives funding from its LLC partners, US defense contracts, and other commercial customers. HRL focuses on advanced developments in microelectronics, information & systems sciences, materials, sensors, and photonics; their workspace spans from basic research to product delivery. It has particularly emphasized capabilities in high performance integrated circuits, high power lasers, antennas, networking, and smart materials. Despite downsizing during the aerospace industry's contraction of the 1990s, HRL still continued to be the largest employer in Malibu. This work was sponsored by the Defense Advanced Research Projects Agency (DOD). The work was monitored by C. M. Huddleston of the Naval Surface Weapons Center. The objective of this study program was to define an optimum technical approach to the longer ranger goal of achieving practical high repetition rate high power "spark gap" switches. Requirements and possible means of extending the state of the art of crossed field closing switches, vacuum spark gap[s,a and pressurized spark gaps are presented with emphasis on reliable, efficient and compact devices operable in burst mode at 250-300 kV, 40-60 kA. >1 kHz with about 50 nsec. rising in about 3 ns. Models of these devices are discussed which are based upon published and generated design data and on underlying physical principles. Based upon its relative advantages, limitations and tradeoffs, the authors conclude that the Hughes Crossatron switch was the nearest term approach to reach the switch goal levels. Theoretical, experimental, and computer simulation models of the plasma show a collective ion acceleration mechanism to be active which is predicted to result in current rise times approaching 10 nsec. A preliminary design concept is presented. For faster rise times we have shown a vacuum surface flashover switch to be an interesting candidate. This device is limited by trigger instabilities and will require further basic development. The problem areas relevant to high pressure spark gaps are reviewed.…