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down quark

noun, Physics.
the quark having electric charge −1/3 times the elementary charge, with strangeness, charm, and other quark quantum numbers equal to 0.
Also called d quark.
Origin of down quark
1975-80 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for down quark
  • The proton is a baryon that consists of two up and one down quark, and the neutron is two down and one up.
  • It is also proven that a down quark disappears and an up quark is produced.
  • There are two up quarks and a down quark in a proton, and two down quarks and an up quark in a neutron.
  • Two up quarks and one down quark make up the proton.
down quark in Science
down quark
A quark with a charge of -1/3. Its mass is greater than that of the electron and the up quark, but smaller than that of all the other quarks. See Table at subatomic particle.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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