DUNE (Deep Underground Neutrino Experiment) is one of the world’s flagship projects in contemporary particle physics. Conducted in the United States, it seeks to deepen scientific understanding of neutrinos—elementary particles that permeate the Universe yet remain poorly understood. The experiment will rely on an intense neutrino beam generated at Fermilab in Illinois and two detector complexes, the most distant of which will be located nearly 1,300 kilometers away at the Sanford Underground Research Facility (SURF) in South Dakota. The neutrino beam will be produced by an accelerator complex centered on PIP II (Proton Improvement Plan II), a new 215 meter long linear accelerator capable of delivering 800 MeV protons at unprecedented intensity.
France’s contribution to PIP II builds on the expertise of CEA’s Institute of Research into the Fundamental Laws of the Universe (CEA Irfu), which has more than two decades of experience designing and manufacturing accelerator components, including cryomodules for major international scientific infrastructures. Working closely with Fermilab, CEA teams developed the LB650 superconducting cryomodules for PIP II. Following the successful validation of their design in 2023, the agreement now enables the start of manufacturing, assembly, and testing of the ten cryomodules. These activities will take place in France at the CEA Paris Saclay site, using facilities currently dedicated to the European Spallation Source (ESS) project and upgraded to meet PIP II requirements.
Beyond its technological significance, the agreement underscores the trust placed in French scientific expertise and marks a new milestone in Franco American cooperation in science and technology. It demonstrates the ability of both countries to combine their strengths on ambitious international research endeavors and to jointly develop the infrastructures needed to address some of the most fundamental questions in physics.