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No abstract

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Accelerator tubes manufactured by NEC were cleaned by the hydrogen arc discharge method and tested on the NEC 3-MV test accelerator. We will discuss the results of this testing program. Generally, we confirm the favorable experience previously obtained by Korschinek, et a!.* The familiar microdischarges exhibited by normal tubes are largely eliminated in arc discharge cleaned tubes. Thus, the arc discharge process has the same observable effect as voltage conditioning. This result suggests that the hydrogen discharge is effective in removing carbon and hydrocarbons from the surface of the accelerator tube.