New collimators for HiLumi LHC: pre-series paving the way to full production

By Emil Kaijanen, Francois-Xavier Nuiry, Stefano Redaelli and Florence Thompson (CERN)

Teams at CERN are working hard to perform essential tests on three pre-series collimators to validate their new designs and give the final green light for the full series production for the High-Luminosity LHC (HiLumi LHC). The pre-series includes a more-traditional single-beam collimator and two new X-series collimators which feature a double-beam design, new for the HiLumi LHC.

This comes after design, prototyping and validation efforts over the past 10 years, and represents a strong collaborative effort between HiLumi Work Package 5 (which deals with beam collimation for the project), several CERN groups and various companies in Europe.

Following manufacture of a large share of the components and the assembly of the collimator bodies by an Italian contractor, and delivery to CERN at the end of 2025, teams at CERN have equipped and installed the collimator bodies onto their supports and performed numerous Site Acceptance Tests (SAT). Once these SAT activities have been completed, the final go-ahead can be given for the remaining 33 series collimators, making this a crucial step for the HiLumi LHC and the first key milestone of production for the collimators.