Printer Friendly
Dictionary, Encyclopedia and Thesaurus - The Free Dictionary
3,913,944,251 visitors served.
forum Join the Word of the Day Mailing List For webmasters
?
Dictionary/
thesaurus
Medical
dictionary
Legal
dictionary
Financial
dictionary
Acronyms
 
Idioms
Encyclopedia
Wikipedia
encyclopedia
?

muon
(redirected from Myon)

   Also found in: Dictionary/thesaurus, Wikipedia 0.01 sec.
muon (my`ŏn), elementary particle elementary particles, the most basic physical constituents of the universe. Basic Constituents of Matter


Molecules are built up from the atom, which is the basic unit of any chemical element.
..... Click the link for more information.
 heavier than an electron electron, elementary particle carrying a unit charge of negative electricity. Ordinary electric current is the flow of electrons through a wire conductor (see electricity). The electron is one of the basic constituents of matter.
..... Click the link for more information.
 but lighter than other particles having nonzero rest mass. The name muon is derived from mu meson, the former name of the particle. The muon was first observed in cosmic rays cosmic rays, charged particles moving at nearly the speed of light reaching the earth from outer space. Primary cosmic rays consist mostly of protons (nuclei of hydrogen atoms), some alpha particles (helium nuclei), and lesser amounts of nuclei of carbon, nitrogen,
..... Click the link for more information.
 by Carl D. Anderson and Seth Neddermeyer in 1936, the year after the existence of a particle of about the same mass had been predicted by Hideki Yukawa. However, the muon's behavior did not conform to that of Yukawa's meson meson [Gr.,=middle (i.e., middleweight)], class of elementary particles whose masses are generally between those of the lepton class of lighter particles and those of the baryon class of heavier particles.
..... Click the link for more information.
 theory (which actually describes the pion pion or pi meson, lightest of the meson family of elementary particles. The existence of the pion was predicted in 1935 by Hideki Yukawa, who theorized that it was responsible for the force of the strong interactions holding the atomic nucleus
..... Click the link for more information.
, discovered more than 10 years later), and the muon is now classed as a lepton lepton [Gr.,=light (i.e., lightweight)], class of elementary particles that includes the electron and its antiparticle, the muon and its antiparticle, the tau and its antiparticle, and the neutrino and antineutrino associated with each of these particles.
..... Click the link for more information.
 rather than a meson. The muon resembles the electron in every way except mass, the muon having 207 times the mass of the electron. Each particle is negatively charged and has a positively charged antiparticle antiparticle, elementary particle corresponding to an ordinary particle such as the proton, neutron, or electron, but having the opposite electrical charge and magnetic moment.
..... Click the link for more information.
; each has half-integer spin and participates in the weak nuclear force force, commonly, a "push" or "pull," more properly defined in physics as a quantity that changes the motion, size, or shape of a body. Force is a vector quantity, having both magnitude and direction.
..... Click the link for more information.
 but not in the strong force; and each has an associated neutrino neutrino [Ital.,=little neutral (particle)], elementary particle with no electric charge and a very small mass emitted during the decay of certain other particles.
..... Click the link for more information.
 and antineutrino. Muons are produced by the weak decay of pions into a muon and a muon antineutrino. The muon differs from the electron in that it is unstable, decaying with an average lifetime of 2.2 × 10−6 sec (2.2 microseconds) into an electron or positron and a pair of neutrinos, but this difference is related to the difference in mass; the electron is stable because there is no lighter particle into which it can decay. Muons can be substituted for electrons in orbit around the nucleus of an atom; the resulting atom is long-lived enough to exhibit behavior that further supports the close resemblance between the muon and the electron. Recent studies of muons have included the production of "muonic atoms" (ordinary atoms to which an orbiting muon is added) and muonium, which consists of an electron in orbit around a positive muon.
muon
a positive or negative elementary particle with a mass 207 times that of an electron and spin ½. It was originally called the mu meson but is now classified as a lepton

muon [′myü‚än]
(particle physics)
Collective name for two semistable elementary particles with positive and negative charge, designated μ+and μ-respectively, which are leptons and have a spin of ½ and a mass of approximately 105.7 MeV. Also known as mu meson.


Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content.
?Page tools
Printer friendly
Cite / link
Feedback
Mentioned in?  References in periodicals archive?   Encyclopedia browser?   Full browser?
No references found
 
The Five-Year Livestock Promotion Plan languished as President Rhee Syngman was overthrown in April 1960 and the opposition Democratic Party established a parliamentary government led by Prime Minister Chang Myon in August 1960.
In 1961, a military coup overthrew the democratic government of Prime Minister Chang Myon, and Chang was taken into house arrest amid rumors that he would shortly be executed.
The fete takes place in the grounds of the hospice, in Myon Lane, Warwick, on Sunday, July 9, from 1.
 
 
 
Encyclopedia
?

Terms of Use | Privacy policy | Feedback | Advertise with Us | Copyright © 2012 Farlex, Inc.
Disclaimer
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.