Drift tubes for a focusing channel of ion linear accelerator

An open-to-vacuum drift tube with nonorganic (i.e. rare-earth) magnetic quadrupole lens elements has been developed. This design almost completely eliminates local deteriorations of vacuum quality leading to multipactor RF discharges. Drift tubes of this type have been manufactured and installed in the 56-MeV proton linac. The resonator would provide an output energy of 10 MeV. Descriptions are given of the permanent magnetic lenses and the mechanical design of the drift tubes. The magnetic performance is summarized.<
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