down quark

American  

noun

Physics.

1. the quark having electric charge −1/3 times the elementary charge, with strangeness, charm, and other quark quantum numbers equal to 0.

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Etymology

Origin of down quark

First recorded in 1975–80

Example Sentences

Lambda particles are baryons, which means they’re a type of hadron made of three quarks: one up quark, one down quark and one strange quark.

From Scientific American

High school physics would have you believe that inside this proton you'll find a simple triad of three fundamental particles called quarks—two up quarks and one down quark.

From Scientific American

For instance, the electron has heavier versions called muons and taus, the up quark has heavier relatives named charm and top quarks, and the down quark is followed by strange and beauty quarks.

From Scientific American

Physicists are also reassessing particle flavor, a quantum property that defines the species of fermion: up quark, down quark, electron, muon, and so on.

From Scientific American

The first family comprises three charged particles — the up quark, the down quark and the electron — and a neutral particle called the electron neutrino.

From Nature