CERN Begins Major Upgrade to Large Hadron Collider's Core Components
Replacement of critical magnet systems marks a new era for particle physics research
1LHC's critical focusing system
The Large Hadron Collider uses specialized magnet configurations called inner triplets to focus particle beams before collisions. These groups of three quadrupole magnets sit near the four main experiments, compressing beams to maximize collision probability. The tighter the beam focus, the higher the luminosity - the rate of particle collisions that generate research data. Current inner triplets have operated since the LHC's construction between 2005-2007.
2HiLumi LHC project milestone
CERN has begun replacing the original inner triplets with more powerful magnets as part of the High-Luminosity LHC upgrade. The first magnet interconnection was recently cut, marking the official start of this multi-year operation. The upgrade aims to significantly boost collision rates when completed in 2029. Director-General Mark Thomson visited ATLAS experiment site to commemorate this phase of the project.
3Technical leap in magnet design
The new inner triplets represent a major technological advancement, replacing niobium-titanium magnets with niobium-sin superconducting coils. These can generate magnetic fields 40% stronger (11.3 tesla) than current systems. The upgrade required years of R&D and involves installing 16 cryostats and 28 cryo-assemblies. Jean-Philippe Tock, LS3 Coordination Team Head, describes this as a major undertaking.
4Targeted experiment upgrades
The new magnets will specifically enhance ATLAS and CMS experiments where higher collision rates are most valuable. ALICE and LHCb experiments won't receive new triplets as their physics programs don't require the same luminosity boost. However, their existing magnets will be upgraded to benefit from overall system improvements. This selective approach optimizes resources for maximum scientific impact.
5Complex replacement operation
Since September 7, CERN teams have been dismantling collider sections near ATLAS and CMS to remove 28 superconducting magnets including the inner triplets. This delicate operation marks the end of an era for hardware that has served since the LHC's construction. The process requires precision handling of complex cryogenic systems that maintain superconducting conditions.
6Generational transition in physics
The magnet replacement represents a handover between generations of accelerator technology. Markus Zerlauth, HiLumi LHC Project Leader, notes the significance of replacing systems that have operated for nearly 20 years. The new triplets will support physics research through the high-luminosity era expected to begin in the 2030s, enabling more precise particle physics measurements.
7Timeline for implementation
The first new quadrupole magnet is scheduled to arrive in the LHC tunnel in early 2029. The full upgrade will take place during the third long shutdown (LS3) of the collider. This carefully planned schedule minimizes disruption to ongoing research while preparing the LHC for its next phase of operation with significantly enhanced capabilities.
8Impact on particle physics
The upgraded inner triplets will enable researchers to collect more collision data, accelerating discoveries in fundamental physics. Higher luminosity means more rare particle interactions can be observed, potentially revealing new physics beyond the Standard Model. This upgrade maintains CERN's position at the forefront of high-energy physics research for decades to come.