Antineutron

Antineutron

The antineutron is the antiparticle of the neutron. It was discovered (in proton-proton collisions in the Bevatron at Berkeley) by Bruce Cork in 1956, a year after the antiproton was discovered. An antineutron has the same mass as a neutron, and no net electric charge. However, it is different from a neutron by being composed of antiquarks, rather than quarks. In particular, the antineutron consists of two anti-down quarks and one anti-up quark.

In theory, an isolated antineutron should decay into an antiproton, a positron and a neutrino, analogously to the decay of the free neutron.

The magnetic moment of the antineutron is the opposite of that of the neutron. It is nowrap|+1.91 µN for the antineutron but nowrap|-1.91 µN for the neutron (relative to the direction of the spin). Here µN is the nuclear magneton.

Since the antineutron is electrically neutral, it cannot easily be observed directly. Instead, the products of its annihilation with ordinary matter are observed.

There are theoretical proposals that neutron-antineutron oscillations exist, a process which would occur only if there is an undiscovered physical process that violates baryon number conservation.

ee also

*list of particles
*antimatter

External links

* [http://pdg.lbl.gov/2005/tables/contents_tables.html LBL Particle Data Group: summary tables]
* [http://arxiv.org/abs/hep-ph/9503300 suppression of neutron-antineutron oscillation]
* [http://science.uwaterloo.ca/~cchieh/cact/nuclear/particles.html Elementary particles] : includes information about antineutron discovery (LINK found BROKEN 20-MAY-2008)
*" [http://www.fnal.gov/pub/inquiring/questions/antineutron.html Is Antineutron the Same as Neutron?] " explains how the antineutron differs from the regular neutron despite having the same, that is zero, charge


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Look at other dictionaries:

  • Antineutron — Propriétés générales Classification Nucléon Composition 1 antiquark 2 antiquarks Propriétés physiques Masse 939,573 MeV …   Wikipédia en Français

  • Antineutrón — Saltar a navegación, búsqueda El antineutrón es la antipartícula del neutrón. Fue descubierto por Bruce Cork en el año 1956, un año después de que el antiprotón fuera descubierto. Un antineutrón tiene la misma masa que un neutrón, y ninguna carga …   Wikipedia Español

  • antineutron — ANTINEUTRÓN, antineutroni, s.m. (fiz.) Antiparticulă a neutronului. [pr.: ne u ] – Din fr. antineutron. Trimis de ana zecheru, 13.09.2007. Sursa: DEX 98  antineutrón s. m. → neutron Trimis de siveco, 13.09.2007. Sursa: Dicţionar ortografic … …   Dicționar Român

  • antineutron — [ ɑ̃tinøtrɔ̃ ] n. m. • 1956; de 1. anti et neutron ♦ Phys. Antiparticule du neutron. ● antineutron nom masculin Antiparticule du neutron. ⇒ANTINEUTRON, subst. masc. PHYS. NUCL. Antiparticule correspondant au neutron dont la masse est égale à… …   Encyclopédie Universelle

  • antineutron — n. The antiparticle of a neutron. It has the same mass as a neutron, but a spin and magnetic moment opposite that of the neutron. [WordNet 1.5] …   The Collaborative International Dictionary of English

  • antineutron — antineùtrōn m <G antineutróna> DEFINICIJA fiz. elementarna čestica bez naboja, antičestica neutronu ETIMOLOGIJA anti + v. neutron …   Hrvatski jezični portal

  • antineutrón — m. Fís. Antipartícula del neutrón …   Diccionario de la lengua española

  • antineutron — ☆ antineutron [an΄tīno͞o′trän΄, an΄tēno͞o′trän΄, an΄tino͞o′trän΄ ] n. the antiparticle of the neutron, with the same mass and spin as the neutron, but with a positive magnetic moment (the neutron has a negative magnetic moment) …   English World dictionary

  • Antineutron — Das Antineutron ist im Standardmodell das Antiteilchen des Neutrons. Nach dem Quarkmodell besteht es aus zwei Anti Down Quarks und einem Anti Up Quark. Das Antineutron wurde 1956, also ein Jahr nach der Entdeckung des Antiprotons, von B. Cork et… …   Deutsch Wikipedia

  • Antineutron — antineutronas statusas T sritis fizika atitikmenys: angl. antineutron vok. Antineutron, n rus. антинейтрон, m pranc. antineutron, m …   Fizikos terminų žodynas

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