CERN chills LHC magnets to -456°F in major step toward 10× more data

CERN has initiated the cryogenic cooldown of a 312-foot-long test stand known as the Inner Triplet String (IT String) as part of the High-Luminosity Large Hadron Collider (HiLumi LHC) upgrade. This full-scale replica of the upgraded magnet system will be chilled to 1.9 Kelvin (-456°F), colder than outer space, to validate the performance of the superconducting niobium-tin inner triplet magnets and associated infrastructure. These magnets are critical for tightly focusing proton beams in the collider and represent a significant advancement over the current niobium-titanium magnets. The cooldown process, which will take several weeks, tests the integration of magnets, cryogenics, protection, and power systems ahead of their installation during the upcoming Long Shutdown 3 (LS3), a four-year overhaul scheduled to begin soon. The HiLumi LHC upgrade aims to increase the collider’s luminosity by a factor of 10, enabling researchers to observe