Another year of outstanding accelerator complex performance

By Mike Lamont

Another fantastic year of LHC proton–proton operation came to an end on 18 November, with 125 fb⁻¹ delivered to both ATLAS and CMS, 12.5 fb⁻¹ to LHCb and a smidgeon to ALICE in line with their more modest proton demands. All this follows the similarly spectacular performance of 2024. Over the full lifetime of the LHC, more than 500 fb⁻¹ have now been delivered to ATLAS and CMS – an extraordinary legacy that should help sustain four years without collisions during Long Shutdown 3 (LS3), which starts for the LHC at the end of June 2026.

Alongside proton running, 2025 included a highly successful light-ion campaign. June saw an intense 12-day block of proton–oxygen, oxygen–oxygen and neon–neon collisions, supported by excellent beam quality and intensity from the ion source through the full injector chain. The year is now concluding with a lead–lead run.