Electron lenses and cooling for the Fermilab Integrable Optics Test Accelerator

TL;DR

This paper discusses the development of nonlinear integrable accelerator lattices at Fermilab's IOTA, utilizing electron lenses for beam cooling, stability, and enhanced performance in high-intensity accelerators.

Contribution

It introduces the application of electron lenses to create nonlinear integrable lattices and explores their potential to improve beam stability and cooling in high-intensity accelerators.

Findings

Design of nonlinear integrable lattices using electron lenses

Potential for improved beam stability and damping

Feasibility of electron cooling with integrable optics

Abstract

Recently, the study of integrable Hamiltonian systems has led to nonlinear accelerator lattices with one or two transverse invariants and wide stable tune spreads. These lattices may drastically improve the performance of high-intensity machines, providing Landau damping to protect the beam from instabilities, while preserving dynamic aperture. The Integrable Optics Test Accelerator (IOTA) is being built at Fermilab to study these concepts with 150-MeV pencil electron beams (single-particle dynamics) and 2.5-MeV protons (dynamics with self fields). One way to obtain a nonlinear integrable lattice is by using the fields generated by a magnetically confined electron beam (electron lens) overlapping with the circulating beam. The required parameters are similar to the ones of existing devices. In addition, the electron lens will be used in cooling mode to control the brightness of the proton beam and to measure transverse profiles through recombination. More generally, it is of great interest to investigate whether nonlinear integrable optics allows electron coolers to exceed limitations set by both coherent or incoherent instabilities excited by space charge.