Coupled - Bunch Beam Breakup due to Resistive - Wall Wake ∗ Jiunn -
نویسندگان
چکیده
The coupled-bunch beam breakup (bbu) problem in a periodic linac excited by the resonance wake is well understood [1–3]. However, there are no systematic studies for the corresponding problem excited by the resistive wall impedance. This study of the resistive wall bbu problem is necessitated by the recently proposed PERL project [4]. For PERL, the light source consists of twelve undulators, each twelve meters long, totally 144 meters. The beam is shielded from the environment by circular copper pipes of a very small radius b=2.5 mm. The proposed injection cycle is twelve hours. It is crucial to know if the PERL beam can survive the bbu. We present our theoretical results for the resistive-wall coupled-bunch beam breakup problem in this paper. Some of the results obtained here has been briefly reported in Ref. [5].
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