CERN releases detailed plans for supercollider — but no hints about funding

CERN’s ambition to build an accelerator three times as large as the Large Hadron Collider (LHC) took a significant step forward on 31 March with the release of a massive feasibility study for the project. But possible scenarios for how to fund the new machine will be presented at a later date.

The European particle physics laboratory near Geneva, Switzerland, has not yet officially decided whether to endorse the 91-kilometre Future Circular Collider (FCC) project or other options for new colliders, but the study will feed into a review of CERN’s long-term strategy that is due to conclude next year.

“This study is the result of an immense amount of work carried out by the international FCC collaboration,” said Fabiola Gianotti, CERN’s director general, in a presentation to reporters. “If approved and implemented, the FCC could become the most extraordinary instrument ever built by humanity to study the laws of nature at the most fundamental level.”

Grand designs

The three-volume feasibility study, to which around 1,500 physicists and engineers have contributed, estimates that it would cost 15.32 billion Swiss francs (US$17.4 billion) to dig a 91-kilometre-long circular tunnel and build a machine to smash together electrons and their antiparticles, positrons, by the mid-2040s. This would enable high-precision studies of the Higgs boson and other known particles.

The biggest machine in science: inside the fight to build the next giant particle collider

A second stage for the project — which would reuse the tunnel and collide two beams of protons, like the LHC — would would not come online until 2072 at the earliest, and would cost 18.8 billion Swiss francs to build. That estimate is based on the assumption that the proton collider will operate at 85 Tera-electronvolts (TeV) — an energy six times higher than the LHC, but lower than the 100 TeV that was proposed initially. Gianotti told reporters that this was a conservative assumption based on using the high-field superconducting magnets — needed to steer protons around the ring — that are available today. Ongoing research on advanced superconducting materials could put higher energies within reach for the 91 km tunnel, perhaps even 120 TeV.

CERN Council president Konstantinos Fountas told reporters that the study will provide “very solid ground” to enable the Council to come to a well-informed decision on whether to go ahead with the project. Antonio Zoccoli, president of Italy’s National Institute of Nuclear Physics and one of country’s delegates to the CERN Council, agrees, saying that the group has done “very solid work” on the technical design and cost estimates.