up quark


Also found in: Dictionary, Thesaurus, Wikipedia.
Related to up quark: down quark

up quark

[′əp ‚kwärk]
(particle physics)
A quark with an electric charge of +⅔, baryon number of ⅓, and 0 strangeness and charm. Symbolized u.
References in periodicals archive ?
The up quark [u.sub.0] and the antiup quark [[bar.u].sub.0] completely annihilate into an electron neutrino [v.sub.e] or an electron antineutrino [[bar.v].sub.e].
The up quark [u.sub.1] and the antidown quark [[bar.d].sub.0] incompletely annihilate into a positive muon [[mu].sup.+].
The up quark [u.sub.1] and the antiup quark [[bar.u].sub.1] completely annihilate into a tau neutrino [v.sub.[tau]] or a tau antineutrino [[bar.v].sub.[tau]].
The up quark [u.sub.1] and the antidown quark [[bar.d].sub.1] incompletely annihilate into a positive lambda [[lambda].sup.+].
The excited antiup quark further degenerates into a ground state up quark and a ground state up and antiup quark pair, [[bar.u].sub.1] [right arrow] [[bar.u].sub.0] + ([u.sub.0][[bar.u].sub.0]).
At the simplest level, a proton consists of three quarks: two up quarks, each with an electric charge of +2/3, and a down quark, with an electric charge of -1/3.
A proton is made up of one down and two up quarks; the neutron reverses those numbers.
At the simplest possible level, a proton consists of three quarks: two up quarks, each with an electric charge of +2/3, and a down quark, with an electric charge of -1/3.