Ion effects in the SLC electron damping ring

Author

Krejcik, P. ; Pritzkau, D. ; Raubenheimer, T. ; Ross, M. ; Zimmermann, F.

Author_Institution

Linear Accel. Center, Stanford Univ., CA, USA

Volume

2

fYear

1997

fDate

12-16 May 1997

Firstpage

1626

Abstract

We report on the ion-related beam behavior in the electron damping ring during unusually poor vacuum conditions in the weeks that followed a catastrophic kicker chamber failure that contaminated the ring vacuum system. The vacuum gradually improved over several months of beam operation, during which time the vertical emittance remained blown up by a factor of 2. The emittance blowup was accompanied by a transverse instability that produced jitter in the extracted beam size. Both the characteristic spectrum of self-excited betatron sidebands and the emittance blowup exhibited a threshold behavior with beam current and vacuum pressure. This behavior depended strongly on the betatron tune and it was found that the ion effects could be minimized by operating just below the 1/2 integer resonance

Keywords

electron accelerators; jitter; linear colliders; particle beam extraction; particle beam stability; storage rings; SLC electron damping ring; Stanford Linear Collider; betatron tune; catastrophic kicker chamber failure; characteristic spectrum; emittance blowup; extracted beam size; ion-related beam behavior; jitter; poor vacuum conditions; ring vacuum system contamination; selfexcited betatron sidebands; threshold behavior; transverse instability; vertical emittance; Contracts; Damping; Electron beams; Electron traps; Fluctuations; Frequency; Light scattering; Production; Protons; Spectral analysis;

fLanguage

English

Publisher

ieee

Conference_Titel

Particle Accelerator Conference, 1997. Proceedings of the 1997

Conference_Location

Vancouver, BC

Print_ISBN

0-7803-4376-X

Type

conf

DOI

10.1109/PAC.1997.750780

Filename

750780