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Quarks
Intermediate
Up, down, charm, strange, top and bottom.
Six flavours: up, down, strange, charm, bottom, top, with charges +2/3 or −1/3. They carry colour and are never seen alone.
Top quark: 173 GeV, as heavy as a gold atom.
Charge fractions of e.
In more detail
Quarks are elementary particles that combine to form protons, neutrons and other hadrons. They come in six flavours and carry fractional electric charges.
Real-world uses
- Quarks explain the structure of protons and neutrons.
- Particle physicists identify quarks through their jets in collisions.
- Physicists use the properties of quarks to explain why protons and neutrons have their masses and charges.
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Frequently asked questions
Why are quarks never seen alone?
Because the strong force confines them inside hadrons.
What are the six flavours?
Up, down, charm, strange, top and bottom.
Why are quarks never seen alone?
Because of confinement, the strong force holds them inside hadrons, and attempts to separate them create new quark pairs.
Related topics in Particle Physics & Cosmology
Elementary particles · Four fundamental forces · Leptons · Hadrons · Antimatter · Gauge bosons