The HOM Study of CESR RF Cavities Using Single Circulating Bunch
نویسندگان
چکیده
The CESR RF system consists of four 5-cell RF cavities 1. Each cell has a eld probe sensitive to the voltage in the cell. We used a single bunch circulating in the ring as the driving current which gives a w ell known spectrum. The signals from the eld probes were analyzed and we were able to identify the peaks seen in the spectra as higher-order modes HOMs that are excited by the beam in RF cavities. Analysis of the peak shapes and location gave us the Q factors of parasitic modes and their frequencies. The reliability of data was veriied with direct measurement using a Network analyzer. The information about Qs and frequencies of the parasitic modes will be used for the multi-bunch beam stability analysis.
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