CEPC accelerator status overview

Abstract In 2012, the Higgs boson was successfully observed at the LHC. Due to the relatively low mass of the Higgs, it is possible to build a Higgs factory using a circular e + e - collider. Consequently, the Circular Electron-Positron Collider (CEPC) was proposed shortly after the observation of the Higgs. After several years of pre-studies, the CEPC study group completed the Conceptual Design Report (CDR) in 2018. Since then, a series of key technology R&D efforts have been carried out, and the accelerator design has been continuously optimized. The accelerator design can meet the scientific objectives by allowing operation at different energies for Higgs/W/Z, and ttbar, with high luminosities. Key technologies required for mass production have been developed, including the high-performance superconducting accelerating cavities and modules, high-efficiency RF power sources, magnets, and vacuum systems, etc,. This paper will present the selected key technology R&D accomplishments and updated accelerator key parameters.