A Genetic Algorithm for Chromaticity Correction in Diffraction Limited Storage Rings

TL;DR

This paper presents a multi-objective genetic algorithm designed to optimize chromaticity correction in diffraction limited storage rings, balancing dynamic aperture and beam lifetime efficiently.

Contribution

It introduces a novel genetic algorithm framework with dominance constraints for effective chromaticity correction in storage rings, specifically tailored for the Swiss Light Source upgrade.

Findings

Optimized chromaticity correction improves dynamic aperture.

Enhanced beam lifetime achieved through the algorithm.

Efficient computational method for storage ring optimization.

Abstract

A multi-objective genetic algorithm is developed for optimizing nonlinearities in diffraction limited storage rings. This algorithm determines sextupole and octupole strengths for chromaticity correction that deliver optimized dynamic aperture and beam lifetime. The algorithm makes use of dominance constraints to breed desirable properties into the early generations. The momentum aperture is optimized indirectly by constraining the chromatic tune footprint and optimizing the off-energy dynamic aperture. The result is an effective and computationally efficient technique for correcting chromaticity in a storage ring while maintaining optimal dynamic aperture and beam lifetime. This framework was developed for the Swiss Light Source (SLS) upgrade project.