CERN releases the FCC feasibility study

(This is the English translation of this post)

A couple of days ago, CERN released the feasibility report for the FCC (Future Circular Collider) project, the future circular accelerator that could be the successor to the LHC. As I have already mentioned on these pages, this is an ambitious project structured in two phases, both housed in a 91 km tunnel to be excavated between Switzerland and France. The first phase would involve an electron-positron collider, a "precision" machine dedicated to measurements of the properties of the Higgs boson and the Standard Model which cannot be performed as effectively with the LHC. The second phase, on the other hand, would see the commissioning of a proton collider similar to the LHC but significantly more powerful, capable of reaching a center-of-mass energy of 100 TeV and exploring new frontiers of fundamental physics.

I have already discussed the scientific and strategic importance of FCC: I truly believe it is the right path to take, both for advancing our understanding of particle physics and for ensuring the training of future physicists and technologists, in addition to promoting cutting-edge technological innovation in Europe. I personally contributed to the recently published feasibility study alongside some colleagues, focusing on a specific aspect of the study of the Higgs boson’s properties.

However, it should be emphasized that this document is "only" a feasibility study: it serves to demonstrate how and what can be achieved, where, and at what cost, but it does not yet represent a definitive decision by CERN’s member states to proceed with the construction of the project. That decision will come later, at the conclusion of the process to update the European Strategy for Particle Physics, which I had already discussed here.

In June, the European particle physics community will gather in Venice to draft a common document representing the community’s consensus on the next steps to take. This document will then be submitted to the CERN Council, which will assess its relevance and, in its scheduled November meeting, may commit member states to the realization of a specific project. The FCC feasibility report is therefore an important step, but the road ahead is still long. In recent months, the debate has been intense and will continue at least until the drafting of the June document and certainly until the November vote, albeit in different settings. I will keep you updated.