Simulation of Hollow Electron Lenses as LHC Beam Halo Reducers using Merlin

The Large Hadron Collider (LHC) and its High Luminosity (HL) upgrade foresee unprecedented stored beam energies of up to 700 MJ. The collimation system is responsible for cleaning the beam halo and is vital for successful machine operation. Hollow electron lenses (HELs) are being considered for the LHC, based on Tevatron designs and operational experience [1], for active halo control. HELs can be used as soft scraper devices, and may operate close to the beam core without undergoing damage [2]. We use the Merlin C++ accelerator libraries [3] to implement a HEL and examine the effect on the beam halo for various test scenarios.