为了平衡机器性能与造价，CEPC提出了局部双环的方案。这是一个全新的环形对撞机方案，许多关键加速器物理与技术问题需要深入研究。其中，动力学孔径是关系到该方案可行性的最为关键的加速器物理问题。本研究将首次对CEPC局部双环方案的动力学孔径问题进行研究。本研究主要包括理论分析CEPC局部双环非线性的产生机制，找出限制环形Higgs工厂动力学孔径的非线性并给出优化方法，然后应用多目标优化算法，快速、有效地优化环形Higgs工厂的动力学孔径。

Dynamic aperture is one of the key issues which determine the feasibility of a circular Higgs factory. This study will mainly study the dynamic aperture of partial double rings scheme for CEPC. This study includes theoretical analysis of the generating mechanism of the nonlinearity in partial double rings, finding out the limits on the dynamic aperture of circular Higgs factory, correction of the nonlinearity, applying multi-objective optimization algorithm on the dynamic aperture study.