Assertion: ion's proton | /r/HasProperty | three valence quarks
Facets:
value: up, up, down
type: OTHER
Source sentences:
text: Protons are composite particles composed of three valence quarks: two up quarks of charge +2/3e and one down quark of charge –1/3e.
text: A modern perspective has a proton composed of the valence quarks (up, up, down), the gluons, and transitory pairs of sea quarks.
text: Protons are spin-½ fermions and are composed of three valence quarks, making them baryons (a sub-type of hadrons).