LHC

The Large Hadron Collider (LHC) is the world's largest and most powerful particle accelerator. It is housed at CERN near Geneva, on the Franco-Swiss border. The LHC consists of a 27-kilometre circular tunnel in which counter-rotating beams of protons or heavy ions are guided and collided at high energies. Its main scientific aim is to study fundamental particles and forces, test predictions of the Standard Model, and search for new phenomena beyond it.

Beams are steered by superconducting magnets made from niobium-titanium and cooled to 1.9 kelvin with liquid helium. The accelerator hosts four large particle detectors at intersection points: ATLAS, CMS, LHCb, and ALICE. Collisions occur every 25 nanoseconds, producing vast numbers of events that are recorded and analyzed by international teams using distributed computing resources.

Since its first physics runs in 2010, the LHC has operated at centre-of-mass energies up to 13 TeV (6.5 TeV per beam) from Run 2 onward. In 2012, ATLAS and CMS announced the discovery of the Higgs boson. The LHC has completed several long shutdowns for upgrades, with Run 3 beginning in 2022 and the High-Luminosity LHC program planning to increase data collection substantially in the coming years.