Chromatic and Dispersive Effects in Nonlinear Integrable Optics

TL;DR

This paper investigates how chromaticity and dispersion influence particle orbits in nonlinear integrable optics, revealing conditions that preserve integrability and improve accelerator performance.

Contribution

It provides a detailed analysis of chromatic and dispersive effects on integrable optics, highlighting conditions to maintain integrability and optimize accelerator design.

Findings

Chromaticity generally breaks integrability unless vertical and horizontal chromaticities are equal.

Equal chromaticities allow weaker correction magnets, preserving dynamic aperture.

Results obtained using Lie operator formalism on particle orbit behavior.

Abstract

Proton accumulator rings and other circular hadron accelerators are susceptible to intensity-driven parametric instabilities because the zero-current charged particle dynamics are characterized by a single tune. Landau damping can suppress these instabilities, which requires energy spread in the beam or introducing nonlinear magnets such as octupoles. However, this approach reduces dynamic aperture. Nonlinear integrable optics can suppress parametric instabilities independent of energy spread in the distribution, while preserving the dynamic aperture. This novel approach promises to reduce particle losses and enable order-of-magnitude increases in beam intensity. In this paper we present results, obtained using the Lie operator formalism, on how chromaticity and dispersion affect particle orbits in integrable optics. We conclude that chromaticity in general breaks the integrability, unless the vertical and horizontal chromaticities are equal. Because of this, the chromaticity correcting magnets can be weaker and fewer correcting magnet families are required, thus minimizing the impact on dynamic aperture.