The interaction of high-energy particles, whose trails reveal internal structures.Particle collisions are the primary experimental tool for probing the subatomic world. When two particles, such as protons or electrons, are accelerated to high energies and smashed together, the energy of the collision can materialize into new particles, or reveal the internal structure of the colliding objects. The trails left by these debris particles in detectors allow physicists to reconstruct what happened in the instant of impact, providing evidence for fundamental particles and forces.
The technique was pioneered in the early 20th century, with the first artificial particle collisions achieved by Ernest Rutherford in 1917, who used alpha particles to disintegrate nitrogen nuclei.
In a collision, the kinetic energy of the incoming particles is converted into mass-energy, creating new particles that fly outward. Detectors track the paths, momenta, and energies of these products. By analyzing the patterns of these tracks, physicists can infer the properties of the original interaction, such as the existence of short-lived intermediate particles or the distribution of quarks and gluons inside protons.
Particle collisions are used in medical imaging (e.g., PET scans) and cancer therapy (hadron therapy), as well as in materials science for analyzing the composition of samples.
The Large Hadron Collider accelerates protons to 99.9999991% the speed of light, and each collision generates temperatures over 100,000 times hotter than the core of the Sun.
