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CERN and Fermilab map out HL-LHC collaboration

A memorandum of understanding (MoU) between CERN and Fermilab, signed on 23 March, details Fermilab’s contributions to the High-Luminosity LHC project


Nigel Lockyer, Director of Fermilab (left, on the screen) and Fabiola Gianotti, CERN Director-General, sign a Memorandum of Understanding in the presence of Mike Lamont, CERN Director for Accelerators and Technology (Image: CERN)

Representatives of CERN and Fermilab have reinforced the collaboration between the two leading particle physics laboratories around the High-Luminosity LHC (HL-LHC) project through the signature of a memorandum of understanding (MoU) detailing the US laboratory’s technical contributions to the accelerator upgrade project. Fabiola Gianotti, Director-General of CERN, and Nigel Lockyer, Director of Fermilab, signed the official document in a ceremony which was held via videoconference on Tuesday, 23 March.

The MoU further defines Fermilab’s involvement in the HL-LHC project, the comprehensive overhaul of CERN’s flagship accelerator which aims for a tenfold increase of integrated luminosity compared to the nominal LHC. Fermilab’s long-standing involvement was formalised in a 2015 cooperation agreement, under which this MoU comes, to transition to final production. Through the signature of the MoU, Fermilab pledges the delivery to CERN of 10 units of Q1 and Q3 inner triplet quadrupole cryo-assemblies and 10 units of radiofrequency dipole crab cavities, two crucial components for the upgrade of the LHC. The MoU also outlines a schedule for the production and delivery of the components (all deliveries are planned to be completed by 2025) and details funding for the project.

The United States, through the Department of Energy and the National Science Foundation, has been heavily involved in CERN activities and vice versa, both within the framework of the HL-LHC project and outside of it. The country was granted Observer status for the project in 2020, shortly after the successful test of short niobium-tin 11 Tesla magnets at Fermilab in the same year. This outstanding achievement was hailed as a milestone on the road to the HL-LHC, which will rely on this technology to focus the intense proton beams. Conversely, the strong performance of the ProtoDUNE installation at CERN, a detector prototype for the future DUNE experiment (Deep Underground Neutrino Experiment), presages the successful development of the large neutrino-detecting experiment on US soil in the coming years.