Hadron (subatomic particle) that is composed of three quarks
Not to be confused with Barium.
"Baryonic" redirects here. For the dinosaur, see Baryonyx.
Standard Model of particle physics
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In particle physics, a baryon is a type of composite subatomic particle, including the proton and the neutron, that contains an odd number of valence quarks, conventionally three.[1] Baryons belong to the hadron family of particles; hadrons are composed of quarks. Baryons are also classified as fermions because they have half-integer spin.
The name "baryon", introduced by Abraham Pais,[2] comes from the Greek word for "heavy" (βαρύς, barýs), because, at the time of their naming, most known elementary particles had lower masses than the baryons. Each baryon has a corresponding antiparticle (antibaryon) where their corresponding antiquarks replace quarks. For example, a proton is made of two up quarks and one down quark; and its corresponding antiparticle, the antiproton, is made of two up antiquarks and one down antiquark.
Baryons participate in the residual strong force, which is mediated by particles known as mesons. The most familiar baryons are protons and neutrons, both of which contain three quarks, and for this reason they are sometimes called triquarks. These particles make up most of the mass of the visible matter in the universe and compose the nucleus of every atom (electrons, the other major component of the atom, are members of a different family of particles called leptons; leptons do not interact via the strong force). Exotic baryons containing five quarks, called pentaquarks, have also been discovered and studied.
A census of the Universe's baryons indicates that 10% of them could be found inside galaxies, 50 to 60% in the circumgalactic medium,[3] and the remaining 30 to 40% could be located in the warm–hot intergalactic medium (WHIM).[4]
^Gell-Mann, M. (1964). "A schematic model of baryons and mesons". Physics Letters. 8 (3): 214–215. Bibcode:1964PhL.....8..214G. doi:10.1016/S0031-9163(64)92001-3.
^Nakano, Tadao; Nishijima, Kazuhiko (November 1953). "Charge Independence for V-particles". Progress of Theoretical Physics. 10 (5): 581–582. Bibcode:1953PThPh..10..581N. doi:10.1143/PTP.10.581. The 'baryon' is the collective name for the members of the nucleon family. This name is due to Pais. See ref. (6).
^J. Michael Shull; et al. (2012). "The Baryon Census in a Multiphase Intergalactic Medium: 30% of the Baryons May Still be Missing". Vol. 759, no. 1. The Astrophysical Journal. doi:10.1088/0004-637X/759/1/23.
^J.-P. Macquart; et al. (2020). "A census of baryons in the Universe from localized fast radio bursts". Vol. 581. Nature. pp. 391–395. doi:10.1038/s41586-020-2300-2.
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Baryons are composite particles made of three quarks, as opposed to mesons, which are composite particles made of one quark and one antiquark. Baryons...
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In cosmology, baryon acoustic oscillations (BAO) are fluctuations in the density of the visible baryonic matter (normal matter) of the universe, caused...
and all composite particles made of an odd number of these, such as all baryons and many atoms and nuclei. Fermions differ from bosons, which obey Bose–Einstein...
quark–antiquark pair (thus have a baryon number of 0), while baryons are made of three quarks (thus have a baryon number of 1). This article discusses...
composite particle, which is composed of other particles (for example, a baryon, like a proton or a neutron, composed of three quarks; or a meson, composed...
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neutron are in a scheme of categories being at once fermions, hadrons and baryons. The proton carries a positive net charge, and the neutron carries a zero...
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any baryon (particle consisting of three quarks) and any antibaryon consisting of three antiquarks, one of which corresponds to a quark in the baryon. (This...
found in isolation; they can be found only within hadrons, which include baryons (such as protons and neutrons) and mesons, or in quark–gluon plasmas. For...
contain an odd number of quarks are called baryons and those that contain an even number are called mesons. Two baryons, the proton and the neutron, make up...
subset of the flavour symmetry seen more broadly in the interactions of baryons and mesons. The name of the concept contains the term spin because its...
composite particles consisting of an odd number of these, such as all baryons and many atoms and nuclei. Fermions have half-integer spin; for all known...
subatomic particles called hadrons such as the J/psi meson and the charmed baryons created in particle accelerator collisions. Several bosons, including the...
topological stability of the skyrmion can be interpreted as a statement that the baryon number is conserved; i.e. that the proton does not decay. The Skyrme Lagrangian...
In particle physics, exotic baryons are a type of hadron (bound states of quarks and gluons) with half-integer spin, but with a quark content different...
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