title: Collimation with hollow electron beams.
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.
authors.affiliation: Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, Illinois 60510, USA. stancari@fnal.gov
authors.forename: G
authors.initials: G
authors.lastname: Stancari
authors.forename: A
authors.initials: A
authors.lastname: Valishev
authors.forename: G
authors.initials: G
authors.lastname: Annala
authors.forename: G
authors.initials: G
authors.lastname: Kuznetsov
authors.forename: V
authors.initials: V
authors.lastname: Shiltsev
authors.forename: D A
authors.initials: DA
authors.lastname: Still
authors.forename: L G
authors.initials: LG
authors.lastname: Vorobiev