Interaction of CESR vacuum pumps with stored beam

The anomalous antidamping of some multibunch modes in the Cornell Electron Storage Ring (CESR) has been shown to depend on the distributed ion pumps being powered. The pumps also modify some other aspects of beam dynamics. These effects were observed in connection with studies of the behavior of the pumps themselves, which is affected in a complicated manner by the circulating beams. The results of some preliminary observations are reported.<
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