The Future Circular Collider (FCC), a plan for a next-gen large-scale circular collider at CERN, is closely related to the ILC project that would be built in Iwate Prefecture. Iwate Nippo asked Prof. Hitoshi Yamamoto of Tohoku University’s Graduate School of Science about the background and future development of the FCC.

They have thought up the 100km FCC project to be the next accelerator to follow the LHC at CERN, a circular collider with a 27-km circumference. In the initial stage of research, they would smash electrons and positrons together in order to precisely measure the Higgs boson, which is the same research and goal as the ILC (a linear collider with an initial length of 20km).

So why is all this sudden movement regarding the FCC project? Well, it’s the same reason why the deadline for Japan to voice its intentions on the ILC has been set for March 2019. The next strategy for European particle physics is being created, and the real work is about to start. If you don’t release information on your project, then it won’t be put into the strategy.

When you think of the cost and amount of human resources needed, it would be impossible to build both a linear collider (ILC) and a circular collider (FCC). Both of the projects are similar in that their initial research will be on the Higgs boson. But afterward, a linear collider would be upgraded for collisions at higher energy levels, and a circular collider would be upgraded to smash protons together. They would evolve in different directions.

Constructing the FCC would take about twice the amount of money as the ILC. I think that CERN would welcome the ILC being realized, and would give up on the FCC and get involved with the ILC. There’s also a concept to build a 100km circumference circular collider in China, but they seem to be have difficult selling the project to the Chinese government. If a go-sign is given for the ILC in Japan, then there’s a high possibility that China would participate in the ILC as well.

If there were enough money and human resources available worldwide, then we could build both the FCC and ILC, and their research would complement each other. However, if only one can be built, and the ILC is the one that is realized, it would reign for many years as the only place to do that kind of particle physics research worldwide. If the ILC is not built, then I think that would be a boon for the CERN and Chinese projects.