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arXiv 1208.20192012-08-09physics.acc-ph

Transverse instability of the antiproton beam in the Recycler Ring

L. R. Prost, C. M. Bhat, A. Burov, J. Crisp, N. Eddy, M. Hu, A. Shemyakin

备注：: 3 pp. Particle Accelerator, 24th Conference (PAC'11) 2011. 28 Mar - 1 Apr 2011. New York, USA

英文摘要：

The brightness of the antiproton beam in Fermilab's 8 GeV Recycler ring is limited by a transverse instability. This instability has occurred during the extraction process to the Tevatron for large stacks of antiprotons even with dampers in operation. This paper describes observed features of the instability, introduces the threshold phase density to characterize the beam stability, and finds the results to be in agreement with a resistive wall instability model. Effective exclusion of the longitudinal tails from Landau damping by decreasing the depth of the RF potential well is observed to lower the threshold density by up to a factor of two.

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