up quark
Quick Summary
The up quark is a fundamental particle that, along with the down quark, forms protons and neutrons. It carries an electric charge of +2/3 e, where e is the elementary charge. Protons are composed of two up quarks and one down quark, resulting in a net charge of +e. Neutrons are made of one up quark and two down quarks, giving them a net charge of zero. These quarks have a spin of 1/2, and their spins align to give protons and neutrons their observed spin of 1/2. Up and down quarks are the lightest of the six known quark flavors.1
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subatomic particleQuarks and antiquarksThese are the up quark, with a charge of +2/3e, and the down quark, which has a charge of −1/3e. The proton consists of two up quarks and one down quark, which gives it a total charge of +e. The neutron, on…
Read MoreThese are the up quark, with a charge of +2/3e, and the down quark, which has a charge of −1/3e. The proton consists of two up quarks and one down quark, which gives it a total charge of +e. The neutron, on…
Read More- subatomic particleFinding the messenger particles
…down quark turns into an up quark to form a proton. Such flavour-changing interactions occur only through the weak force and are described by the SU(2) symmetry that underlies electroweak theory along with U(1). The basic representation of this mathematical group is a pair, or doublet, and, according to electroweak…
Read More…down quark turns into an up quark to form a proton. Such flavour-changing interactions occur only through the weak force and are described by the SU(2) symmetry that underlies electroweak theory along with U(1). The basic representation of this mathematical group is a pair, or doublet, and, according to electroweak…
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