The Transverse Wakefield of a Detuned X-band Accelerator Structure*
نویسنده
چکیده
In the design of future electron/positron colliders in the TeV region with high luminosities, the transverse wakefields generated by one bunch in a train of accelerated bunches may deflect one or more of the subsequent bunches. In this paper we analyze the mode structure and the transverse wakefields in a tapered cavity, including the effect of coupling between adjacent cells. The parameters of the equivalent circuit chain used in the analysis are obtained from computer runs for periodic structures corresponding to different cells of the cavity. Following the guidelines suggested by an analysis of Maxwell’s equations for one or two deflecting bands we obtain numerical solutions for the wakefields for different patterns of detuning. We find that Gaussian detuning of the geometric cell parameters within a8 cavity dramatically decreases the wakefields obtained with linear detuning. Several examples of mode structure, mode frequency distribution, kick factors, and wakefields are presented, confirming this conclusion.
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