Inside a Particle Collision
At the Large Hadron Collider, protons circulate in opposite directions at 99.9999991% the speed of light. When they collide head-on, their kinetic energy converts into mass, creating showers of new particles. Each collision is a miniature recreation of conditions that existed fractions of a second after the Big Bang.
Reading an Event Display
An event display is a visual representation of what happened in a single collision. Tracks radiate from the central collision point, curved by the detector's powerful magnetic field. The curvature reveals each particle's momentum and charge. Energy deposits in the outer calorimeters appear as colored blocks proportional to the energy deposited. Gaps in the energy budget indicate invisible neutrinos.
Types of Collision Events
Most collisions produce ordinary jets of hadrons — sprays of protons, pions, and kaons. Rare events are far more interesting: Higgs boson production occurs only once in 10 billion collisions, top quark pairs require enormous energy, and W/Z boson events are key signatures of the electroweak force. Heavy-ion collisions can create quark-gluon plasma, a new state of matter.
From Data to Discovery
The LHC produces about 600 million collisions per second, but only a tiny fraction are recorded. Sophisticated trigger systems filter events in real time, keeping only those with signatures of interesting physics. The discovery of the Higgs boson in 2012 required analyzing billions of recorded events to find the statistical excess that revealed the new particle.