Nonlinear optimization for a low-emittance storage ring.

Abstract

A multi-objective genetic algorithm (MOGA) is a powerful global optimization tool, but its results are considerably affected by the crossover parameter η_c. Finding an appropriate η_c demands too much computing time because MOGA needs be run several times in order to find a good η_c. In this paper, a self-adaptive crossover parameter is introduced in a strategy to adopt a new η_c for every generation while running MOGA. This new scheme has also been adopted for a multi-generation Gaussian process optimization (MGGPO) when producing trial solutions. Compared with the existing MGGPO and MOGA, the MGGPO and MOGA with the new strategy show better performance in nonlinear optimization for the design of low-emittance storage rings.