Measurements on prototype cavities (352 MHz) for the Advanced Photon Source (APS)

Measurements of the higher order modes of a prototype single-cell 352-MHz cavity for the APS 7-GeV storage ring are presented and discussed. A 352-MHz cylindrical pill-box cavity made of aluminum has been built to test and verify the measurement instruments using the analytically derived resonant frequencies of both the fundamental and higher-order modes. A cavity made from solid copper was built according to dimensions derived from URMEL program runs. The longitudinal and transverse impedances of the first several higher-order modes have been measured using various shaped metal beads.<
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