CERN Council Decides on Strategy Update: FCC-ee to Become LHC Successor

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The European Organization for Nuclear Research CERN has taken a groundbreaking step towards its scientific future: On May 22, 2026, the CERN Council updated the European Strategy for Particle Physics, recommending the “Electron-Positron Future Circular Collider” (FCC-ee) as the preferred next large-scale project. The strategy update was initiated in March 2024 and is based on 263 written submissions from the global particle physics community. The recommendations of the European Strategy Group were presented to the CERN Council in December 2025 and form the basis of the resolution now adopted.

Higgs Boson at the Center

Of greatest interest in this long-term planning is the Higgs boson. Since its discovery at the LHC in 2012, it has been considered a central tool for answering open questions about the structure and evolution of the universe. According to CERN, the FCC-ee would offer the broadest exploration program in fundamental physics – with outstanding discovery potential around the Higgs boson and other elementary particles, as well as opportunities to discover new physics beyond the Standard Model.

However, according to the strategy update, the highest priority in the medium term is to fully exploit the scientific potential of the existing LHC by completing its High-Luminosity upgrades (HiLumi LHC). The LHC is scheduled to remain in operation until 2041.

Gigantic Construction Project with Impressive Energies

The FCC-ee would be a massive infrastructure project: CERN had already presented the concept in 2019 – a circular accelerator in a tunnel approximately 91 km long, about 200 meters underground, with a circumference almost as large as the Geneva basin. For comparison, the LHC has a circumference of only 27 km.

The reason for the sheer size lies in physics: electrons and positrons lose energy in the form of synchrotron radiation when passing through curves – the smaller the ring radius, the greater this loss. To make higher collision energies economically feasible, the ring must therefore necessarily be larger. As reported by the in-house CERN Courier, the FCC-ee is planned as a double-ring collider with four interaction points. It is intended to achieve center-of-mass energies of up to 365 GeV – significantly more than the 209 GeV maximum achieved by its predecessor, LEP. As a Higgs, electroweak, and top quark factory, it is expected to produce, among other things, approximately 6 × 10¹² Z bosons, nearly 3 × 10⁶ Higgs bosons, and 2 × 10⁶ top quark pairs over 15 years of operation.

In a second step, a hadron collider (FCC-hh) with collision energies of up to 100 TeV could follow in the same tunnel – more than seven times the energy the LHC will reach in its final upgrade stage. CERN Director-General Mark Thomson emphasized that the FCC-ee would deepen knowledge of the fundamental building blocks of the universe through “ultra-precise measurements of the Higgs boson and other elementary particles.”

The completed feasibility study for the FCC concludes that the FCC-ee is “technically ready for construction” – it was published in March 2025 and reviewed by the CERN Council in November 2025.

Financing: Billions Sought

Financing remains the greatest challenge. The costs for the first project phase are estimated at 16 billion euros. In December 2025, several IT and internet billionaires pledged a total of 860 million euros, including the foundation of former Google CEO Eric Schmidt, French internet billionaire Xavier Niel, Italian entrepreneur John Elkann, and the Breakthrough Prize Foundation.

The CERN Council has now tasked management with initiating discussions with relevant authorities and institutions in the member and associate member states, as well as with the European Union, to develop a financially viable funding plan. Annual reports are intended to support national decision-making processes. Public consultations in the CERN host countries, France and Switzerland, are also planned.

Decision by 2028

A decision by the CERN member states and international partners is expected around 2028. Various sources, including a recent study in the journal “Frontiers in Physics,” consistently name the mid-to-late 2040s as the targeted start of operation for the FCC-ee – seamlessly following the end of the LHC era.

Council President Costas Fountas expressed confidence: The particle physics community and the CERN Council agree that the FCC-ee is the preferred flagship project to secure CERN's world-leading role in accelerator physics in the coming decades.

The discoveries such a collider could enable are already hinted at by current research at the LHC: In March 2026, the LHCb collaboration reported the discovery of a new, proton-like particle.

(vza)