Constituent quark

Constituent quark: A constituent quark is a current quark with a covering.

In the low energy limit of QCD, a description by means of perturbation theory is not possible. Here, no Asymptotic freedom exists, but the interactions between valence quarks and sea quarks gain strongly on significance. Part of the effects of virtual quarks and virtual gluons in the 'sea' can be assigned to a quark so well that the term 'constituent quark' seems appropriate.

According to the Feynman diagrams, constituent quarks seem to be 'dressed' current quarks, i.e. current quarks surrounded by a cloud of virtual quarks and gluons. This cloud in the end explains the large constituent-quark masses.

Definition: Constituent quarks are valence quarks for which the correlations for the description of hadrons by means of gluons and sea-quarks are put into effective quark masses of these valence quarks.

The effective quark mass is called constituent quark mass. Hadrons consist of 'glued' constituent quarks. The use of positions for the light constituent quarks is not exactly unproblematic in the description of hadrons.

Binding energy

The quantum chromodynamic binding energy of a valence quark in a hadron is the amount of energy required to make the hadron spontaneously emit a meson containing the valence quark. This is the same as the constituent quark mass.

Constituent quark Mass Δx

Up quark 308 MeV/c²^{[citation needed]} 0.7 fm^{[citation needed]}

Down quark 308 MeV/c²^{[citation needed]} 0.7 fm^{[citation needed]}

Strange quark 483 MeV/c²^{[citation needed]}

Charm quark

Bottom quark

Top quark

Describing hadrons using non-relativistic quantum mechanics becomes difficult.

Categories:
Quarks
Nuclear and atomic physics stubs

Constituent quark	Mass	Δx
Up quark	308 MeV/c²^{[citation needed]}	0.7 fm^{[citation needed]}
Down quark	308 MeV/c²^{[citation needed]}	0.7 fm^{[citation needed]}
Strange quark	483 MeV/c²^{[citation needed]}
Charm quark
Bottom quark
Top quark

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Constituent quark

Binding energy

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Constituent quark

Binding energy

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