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Hadrons
Intermediate
Particles made of quarks: baryons and mesons.
Composite particles of quarks held by the strong force: baryons (three quarks: proton, neutron) and mesons (quark–antiquark: pion, kaon). Hundreds exist.
π⁺ = u d̄.
Pentaquarks and tetraquarks were found by LHCb.
In more detail
Hadrons are composite particles made of quarks, including baryons such as protons and neutrons, and mesons such as pions. They are held together by the strong force.
Real-world uses
- Protons and neutrons are hadrons that make up atomic nuclei.
- Pions are exchanged between nucleons to produce the nuclear force.
- Particle physicists identify protons, neutrons, pions and kaons in collider data by their quark content and decay products.
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Frequently asked questions
What is the difference between baryons and mesons?
Baryons contain three quarks, while mesons contain a quark and an antiquark.
Why are most visible hadrons protons and neutrons?
Because they are stable, while heavier hadrons decay quickly.
What is the difference between a baryon and a meson?
Baryons are made of three quarks, while mesons are made of a quark and an antiquark.
Related topics in Particle Physics & Cosmology
Four fundamental forces · Leptons · Quarks · Antimatter · Gauge bosons · Higgs boson