Hollow electron lenses for beam collimation at the High-Luminosity Large Hadron Collider (HL-LHC)

Abstract Electrons lenses produce a high-intensity electron beam and have variety of applications to circular hadron accelerators. Electron beams different transverse cross sections distributions may be designed, depending on the desired application, they are produced steered along orbit beam, overlapping with it for typical distances few meters before being deflected away disposed of. Hollow find collimation machines like CERN Large Hadron Collider (LHC). Such devices can integrated in system improve halo-cleaning performance through an active control halo dynamics: annular distribution electrons excites resonantly tails surrounding core, while core itself remains unperturbed, as ideally only “sees” field-free “hole” distribution. part upgrade baseline High-Luminosity project LHC (HL-LHC) will installed machine during long shutdown 2025–2027 mitigate effects from losses so performance. This paper describes hollow lens within HL-LHC upgrade.