Starting in 2018, a team of experts from the company General Electric (GE) worked with the Magnets, Superconductors and Cryogenics (TE-MSC) group at CERN to manufacture superconducting coils for the new 11 T dipoles being developed for the HL-LHC project. In January, following three years of fruitful collaboration, the 15-strong team left the Laboratory.

The 11 T dipoles are based on superconducting niobium–tin (Nb3Sn). They are just six metres long but, thanks to their higher field, they might be able to replace some of the main 15-metre-long LHC dipoles in strategic parts of the accelerator, notably at Point 7, freeing up space for new collimators. The plan is to install a total of four 11 T dipoles for the HL-LHC.

“From the very beginning, we established a relationship of trust between the CERN and GE teams to ensure knowledge transfer and cross-fertilisation,” explains Arnaud Devred, leader of the Magnets, Superconductors and Cryogenics group. “We have learned from their industrial approach and their organisational structure, using production units, which has helped us to improve our quality assurance. As for GE, they have developed specific skills in the manufacture of superconducting magnets thanks to their work on the 11 T dipoles, a new technology that is still evolving.”

A total of 35 coils have been manufactured and assembled in the Large Magnet Facility on the Meyrin site, using tools provided by CERN. They will form part of the 11 T dipoles, which may be installed in the LHC during a future technical stop.