top quark(redirected from Heaviest subatomic particle)
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top quark[′täp ‚kwärk]
A hypothetical quark that is postulated to have a mass of approximately 30-50 GeV, electric charge of +⅔, baryon number of ⅓, zero isotopic spin, strangeness, and charm, and a new quantum number associated with it. Also known as t quark; truth quark. Symbolized t.