ElQA: ensuring electrical integrity in the LHC

Ongoing upgrades on the road to HiLumi ElQA: ensuring electrical integrity in the LHC 3 September 2026 The LHC has more than 1600 superconducting electrical circuits powering the magnets guiding the particle beams around the 27 km circumference of the accelerator. Every time the LHC stops for a major shutdown, all these circuits must be carefully checked for any problems. This is the job of the Electrical Quality Assurance (ElQA) team. The work consists of three phases. During the first phase, the sectors are tested under cryogenic conditions, carefully monitored during the warm-up and tested again at room temperature to assess the impact of several years of operation and the subsequent warm-up. In the second phase, the ElQA team supports LS3 activities in the LHC, notably the replacement of four magnets, the repair of 11 cold bypass diodes, and the installation of the new High-Luminosity magnets around the ATLAS and CMS experiments. Finally, at the end of LS3, each sector will again be tested before, during and after the cool-down of the magnets in order to find and fix any electrical problem as early as possible. The circuits will then be ready for hardware commissioning before r