Energy Frontier Accelerators, ILC and FCC

Abstract

The elementary particle physics has been progressing with developments of energy-frontier accelerator projects. The luminosity upgrade of the LHC experiment is scheduled, and discussions on further energy-frontier experimental projects are ongoing among the worldwide high energy physics community. In this article, I review physics motivations for future elementary particle physics experiments with special emphasis on the Higgs physics, and describe status and prospects of two planned projects, namely International Linear Collider (ILC) and Future Circular Collider (FCC).