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How are quarks combined to form a neutron?

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subatomic particle The Large Hadron Collider (LHC), the world's most powerful particle accelerator. At the LHC, located underground in Switzerland, physicists study subatomic particles.

A neutron is a composite subatomic particle classified as a baryon, meaning it is built from three elementary particles called quarks. Specifically, a neutron is composed of one up quark (with a charge of +2/3e) and two down quarks (each with a charge of -1/3e), resulting in a net electric charge of zero.123

These quarks are bound together within the neutron by the strong force, which is mediated by the exchange of massless gauge bosons called gluons. According to the theory of quantum chromodynamics, quarks carry a property known as "colour charge" (red, green, or blue). The strong force ensures that quarks combine only in ways that result in a net colour charge of zero; in the case of the neutron, the three quarks possess different colours that neutralize one another. Because of the extreme strength of this interaction, quarks are permanently confined within the neutron and cannot be isolated.452