Jet (particle physics)

A jet is a narrow, collimated spray of hadrons produced when a high-energy quark or gluon fragments and hadronizes. Its particles collectively approximate the direction and energy of the initiating parton.

Quantum chromodynamics: The quantum field theory describing the strong interaction among quarks and gluons. Its interactions initiate showers that develop into jets.
Quark: An elementary fermion that carries color charge and participates in the strong interaction. A high-energy quark can initiate a jet.
Hadron collider: A particle accelerator that collides hadrons, such as protons, at high energies. Hadron colliders produce large samples of jets from strong-interaction collisions.
Quark jet: A jet initiated by a quark, typically narrower and less particle-rich than a gluon jet. Its radiation pattern differs statistically from jets initiated by gluons.
Parton shower: A sequence of quark and gluon emissions that approximates radiation in high-energy particle collisions. Repeated emissions broaden the initiating parton into a cascade before hadronization.
Gluon: The massless gauge boson that mediates the strong interaction and carries color charge. A gluon can initiate a jet and often produces a wider shower than a quark.
Large Hadron Collider: A proton-proton collider at CERN with a 27-kilometer circumference. Its detectors reconstruct jets in searches and precision measurements.
Gluon jet: A jet initiated by a gluon, typically broader and more particle-rich than a quark jet. Comparing it with quark jets tests predictions of quantum chromodynamics.
Hadronization: The nonperturbative process by which quarks and gluons become color-neutral hadrons. It converts the shower’s partons into the hadrons that make up a jet.
Hadron: A composite particle made of quarks bound by the strong interaction. Hadrons are the observable particles collected into jets.

Linked from 10 pages