CERN member states: further studies on new mega accelerator FCC

10 November 2025

At a special meeting at CERN, member states decided to continue studies into a future circular particle accelerator. The project is favoured, but more homework is needed, according to the council.

Impression of the FCC accelerator. IMAGE PIXELRISE

This is evident from the final statement of the CERN Council meeting that took place in Geneva at the end of last week to assess the completed feasibility study for the FCC accelerator. The CERN Council is the meeting of member states of the lab, of which the Netherlands is also a part.

The FCC feasibility study was published in March with the conclusion that there are no showstoppers for the giant circular accelerator. The machine is feasible and is expected to yield many important physics discoveries.

European strategy

Work on a possible FCC is taking place within the framework of a renewed strategy for European particle physics (ESPP), which is due to be completed in May 2026. The first version of the strategy will be written during a meeting in Switzerland in December this year.

The FCC feasibility study is the work of more than a thousand experts in particle physics and accelerator technology, and was emphatically embraced by the Council. The project fits in with CERN’s ambition to remain the world’s leading laboratory for particle research. CERN Director Fabiola Gianotti called the report ‘a remarkably broad and in-depth study’.

91 kilometres

According to the feasibility study, the Future Circular Collider (FCC), as the project is provisionally named, could become a mega-accelerator with a circumference of 91 kilometres southeast of Geneva. The FCC would be the successor to the current LHC, a 27-kilometre proton collider at CERN with 7 TeV of energy. The FCC could ultimately produce 100 TeV collisions.

The Council is asking for further studies in a number of non-technical areas in order to be able to make a proper assessment. These include landscape and environmental impact, reducing cost uncertainty, finding funding and communicating the societal benefits of the new accelerator.

Various scenarios

The cost of an FCC accelerator is currently estimated at 15-34 billion euros, spread over several decades. Various scenarios are possible for the project.

In an initial phase, it could fire electrons at each other for the production and in-depth study of Higgs particles. In a later phase, proton collisions could be used to search for as yet unknown forces and particles. This would require, among other things, much better magnet technology.

Plan B desired

European countries have until the end of this week to contribute to the ESPP strategy discussions. The Netherlands will also designate FCC as its first choice, but will insist on a suitable plan B in case the mega accelerator proves unfeasible.

According to the schedule, the CERN Council will make a decision on the possible construction of the new accelerator in approximately 2028. Construction could start in the early 2030s, after which the physics measurement programme could begin in the 2040s.