The octet of light spin-1/2 baryons.

In particle physics, the baryons are a family of subatomic particles including the proton and the neutron (collectively called nucleons), as well as a number of unstable, heavier particles (called hyperons). The term "baryon" is derived from the Greek barys, meaning "heavy," as they are heavier than the other main groups of particles. Particles erupt from the collision point of two relativistic (100 GeV per nucleon) gold ions in the STAR detector of the Relativistic Heavy Ion Collider. ... A subatomic particle is a particle smaller than an atom: it may be elementary or composite. ... Properties In physics, the proton (Greek proton = first) is a subatomic particle with an electric charge of one positive fundamental unit (1. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ... In physics a nucleon is a collective name for the two baryons: the neutron and the proton. ... In particle physics, the baryons are a family of subatomic particles including the proton and the neutron (collectively called nucleons), as well as a number of unstable, heavier particles (called hyperons). ...

Baryons are strongly interacting fermions — that is, they experience the strong nuclear force and are described by Fermi-Dirac statistics, which apply to all particles obeying the Pauli exclusion principle. This is in contrast to the bosons, which do not obey the Exclusion principle. In particle physics, fermions, (named after Enrico Fermi), are particles with semi-integer spin. ... The strong nuclear force or strong interaction (also called color force or colour force) is a fundamental force of nature which affects only quarks and antiquarks, and is mediated by gluons in a similar fashion to how the electromagnetic force is mediated by photons. ... Fermi-Dirac statistics - Wikipedia, the free encyclopedia /**/ @import /skins-1. ... The Pauli exclusion principle is a quantum mechanical principle formulated by Wolfgang Pauli in 1925, which states that no two identical fermions may occupy the same quantum state. ... In physics, bosons, named after Satyendra Nath Bose, are particles with integer spin. ...

Baryons, along with mesons, belong to the family of particles known as hadrons, meaning they are composed of quarks. Baryons are fermions composed of three quarks, while mesons are bosons composed of a quark and an antiquark. The quark model classification of baryons is based on this construction. This article needs to be cleaned up to conform to a higher standard of quality. ... In particle physics, a hadron is a subatomic particle which experiences the strong nuclear force. ... Quarks are one of the two basic constituents of matter in the Standard Model of particle physics. ... The quark model is a classification scheme for hadrons in terms of their valence quarks, ie, the quarks (and antiquarks) which give rise to the quantum numbers of the hadrons. ...

In addition to the nucleons (protons and neutrons), other members of the baryon family include the Δ, Λ, Σ, Ξ and Ω particles. For other uses, see Delta. ... Lambda (upper case Λ, lower case λ) is the 11th letter of the Greek alphabet. ... Sigma (upper case Σ, lower case σ, alternative ς) is the 18th letter of the Greek alphabet. ... Xi (upper case Ξ, lower case ξ) is the 14th letter of the Greek alphabet. ... Omega (Ω ω) is the 24th and last letter of the Greek alphabet. ...

Delta baryons (Δ⁺⁺, Δ⁺, Δ⁰, Δ⁻) are composed of a combination of up and down quarks such that the total spin is 3/2. They primarily decay into a pion and either a proton or neutron. In particle physics, pion (short for the Greek pi meson = P middle) is the collective name for three subatomic particles discovered in 1947: Ï€0, Ï€+ and π−. Pions are the lightest mesons. ... Properties In physics, the proton (Greek proton = first) is a subatomic particle with an electric charge of one positive fundamental unit (1. ... Properties In physics, the neutron is a subatomic particle with no net electric charge and a mass of 939. ...

Lambda baryons (Λ⁰) are composed of one up, one down, and one strange quark, with the up and down quarks in an isospin 0 (flavor-antisymmetric) state. The neutral lambda provided the first observational evidence of the strange quark. Isospin (isotopic spin, isobaric spin) is a physical quantity which is mathematically analogous to spin. ...

Sigma baryons (Σ⁺, Σ⁰, Σ⁻), are also composed of one strange quark and a combination of up and down quarks, but arranged in an isospin 1 state. The neutral sigma has the same quark composition as the neutral lambda (up, down, strange), and so decays much faster than either Σ⁺ (up, up, strange) or Σ⁻ (down, down, strange).

Xi baryons, (Ξ⁰, Ξ⁻), are composed of two strange quarks and either an up or down quark. The neutral xi, Ξ⁰, composed of an up and two strange quarks, decays into a neutral lambda and a neutral pion, which itself rapidly decays into two photons. In physics, the photon (from Greek φως, phōs, meaning light) is the quantum of the electromagnetic field; for instance, light. ...

The omega minus baryon (Ω⁻) is composed of three strange quarks. Its discovery was a great triumph in the study of quark processes, since it was found only after its existence, mass, and decay products had already been predicted.

There are additional baryon states which contain heavy quarks. These are denoted by the Greek letter corresponding to their light (up/down/strange) flavor content with a subscript indicating that a strange quark should be replaced by a heavier quark. For example, the Λ⁺_c has quark content (charm, up, down) instead of (strange, up, down).

Baryonic matter

Baryonic matter is matter composed mostly of baryons (by mass), which includes atoms of any sort (and thus includes nearly all matter that we may encounter or experience in everyday life, including our bodies). Non-baryonic matter is the fundamental antithesis of such matter, being any sort of matter that is not primarily composed of baryons. This might include such ordinary matter as neutrinos, photons or free electrons; however, it may also include exotic species of non-baryonic dark matter, such as supersymmetric particles, axions or black holes. The distinction between baryonic and non-baryonic matter is important in cosmology, because Big Bang nucleosynthesis models set tight constraints on the amount of baryonic matter present in the early universe. Matter is commonly defined as the substance of which physical objects are composed. ... Properties Mass: || ≈ 1. ... Look up Experience in Wiktionary, the free dictionary This article discusses the general concept of experience. ... Antithesis (Greek for setting opposite, from anti = against and thesis = position) means a direct contrast or exact opposition to something. ... The neutrino is an elementary particle. ... Properties The electron is a fundamental subatomic particle that carries a negative electric charge. ... In cosmology, dark matter refers to hypothetical matter particles, of unknown composition, that do not emit or reflect enough electromagnetic radiation to be detected directly, but whose presence can be inferred from gravitational effects on visible matter such as stars and galaxies. ... This article is in need of attention from an expert on the subject. ... The axion is a hypothetical exotic particle postulated by Peccei-Quinn theory to resolve the strong-CP problem in quantum chromodynamics (QCD). ... A black hole is a concentration of mass great enough that the force of gravity prevents anything past its event horizon from escaping it except through quantum tunnelling behaviour (known as Hawking Radiation). ... Cosmology, from the Greek: κοσμολογία (cosmologia, κόσμος (cosmos) world + λογια (logia) discourse) is the study of the universe in its totality and by extension mans place in it. ... According to the Big Bang theory, the universe emerged from an extremely dense and hot state (bottom). ... Nucleosynthesis is the process of creating new atomic nuclei either by nuclear fusion or nuclear fission. ... This article needs to be updated. ...

The very existence of baryons is also a significant problem in cosmology, since we have assumed that the Big Bang produced a state with equal amounts of baryons and anti-baryons. The process by which baryons come to outnumber their antiparticles is called baryogenesis (in contrast to a process by which leptons account for the predominance of matter over antimatter, leptogenesis). Baryogenesis is the generic designation for the physical processes that generate matter (more specifically, a class of fundamental particle called baryon) from an otherwise matter-empty state (such as it is generally believed to be the state of the Universe at its onset, the so-called Big Bang). ... In physics, leptogenesis is a process which creates leptons. ...

See also

• List of baryons
• Baryon number
• Particle physics
• Pentaquark
• List of particles
• Proton decay

A list of baryons. ... In particle physics, the baryon number is an approximate conserved quantum number. ... Particles erupt from the collision point of two relativistic (100 GeV per nucleon) gold ions in the STAR detector of the Relativistic Heavy Ion Collider. ... A pentaquark is a subatomic particle consisting of a group of five quarks (compared to three quarks in normal baryons and two in mesons), or more specifically four quarks and one anti-quark. ... This is a list of particles in particle physics, including currently known and hypothetical elementary particles, as well as the composite particles that can be built up from them. ... The standard model of particle physics states that protons are stable, i. ...