Mechanical results of the CEBAF cavity series production

Interface dimensions of the full production run of 360 CEBAF cavities manufactured by Siemens are summarized. Analysis indicates that length tolerances of /spl plusmn/2 mm and fundamental power coupler location tolerances of /spl plusmn/0.15 mm are achievable on future procurements. Vacuum leaks were a concern early in production but have now been overcome: 2 K helium leak rates integrated over 22 vacuum seals have been measured on 84 cavity pairs and a roughly normal distribution of the log/sub 10/ (leak rate) is seen, centered about a rate of 10/sup -10.2/ torr-1/s.<
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