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Observation of Vertical Betatron Sideband due to Electron Clouds in the KEKB LER

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 نشر من قبل John Flanagan
 تاريخ النشر 2004
  مجال البحث فيزياء
والبحث باللغة English
 تأليف J. W. Flanagan




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The effects of electron clouds on positively-charged beams have been an active area of research in recent years at particle accelerators around the world. Transverse beam-size blow-up due to electron clouds has been observed in some machines, and is considered to be a major limiting factor in the development of higher-current, higher-luminosity electron-positron colliders. The leading proposed mechanism for beam blow-up is the excitation of a fast head-tail instability due to short-range wakes within the electron cloud. We present here observations of betatron oscillation sidebands in bunch-by-bunch spectra that may provide direct evidence of such head-tail motion in a positron beam.



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