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arXiv · 1105.3256

Collimation with hollow electron beams

G. Stancari·A. Valishev·G. Annala·G. Kuznetsov·V. Shiltsev·D. A. Still·L. G. Vorobiev
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Abstract

A novel concept of controlled halo removal for intense high-energy beams in storage rings and colliders is presented. It is based on the interaction of the circulating beam with a 5-keV, magnetically confined, pulsed hollow electron beam in a 2-m-long section of the ring. The electrons enclose the circulating beam, kicking halo particles transversely and leaving the beam core unperturbed. By acting as a tunable diffusion enhancer and not as a hard aperture limitation, the hollow electron beam collimator extends conventional collimation systems beyond the intensity limits imposed by tolerable losses. The concept was tested experimentally at the Fermilab Tevatron proton-antiproton collider. The first results on the collimation of 980-GeV antiprotons are presented.

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G. Stancari, A. Valishev, G. Annala, G. Kuznetsov, V. Shiltsev, D. A. Still, L. G. Vorobiev. 2011-07-11. Collimation with hollow electron beams. https://doi.org/10.1103/physrevlett.107.084802

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