Transverse Collective Instability in the Psr
نویسنده
چکیده
An instability in the Proton Storage Ring (PSR) is observed as fast loss of beam during accumulation and storage when the injected beam current exceeds a threshold value. Experimental study results of that instability are presented in this paper. The instability threshold depends significantly on rf voltage, injected momentum spread, and PSR sextupole and octupole strengths. The results are consistent with the hypothesis that the instability is a transverse instability excited by a transverse impedance ZJ.. with IZJ..I == 1 MQ/m. The driving impedance has significant magnitude in the 30to 300-MHz frequency range.
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