positron

From positive + -tron (electron). Coined by American physicist Carl Anderson in 1932 to replace the earlier term antielectron.

coin

The notion of a positron weapon remains the stuff of science fiction.

If these particles carry unit positive charge the curvatures and ionizations produced require the mass to be less than twenty times the electron mass. These particles will be called positrons.

[1933 March 15, Carl D. Anderson, “The Positive Electron”, in Physical Review, volume 43:

(physics) The antimatter equivalent of an electron, having the same mass but a positive charge.


electron

Blend of electric + ion, coined by Anglo-Irish scientist George Stoney in 1891, changed by him multiple times from an earlier electrolion and original electrine (used as early as 1874) as the name for the electric charge associated with a univalent ion. Compare electro-, -on.
The particle ("corpuscule") was discovered in 1896. The name electrion was proposed for the particle in 1906 but curtailed because Hendrik Lorentz preferred electron.

monochromated scanning transmission electron microscope

Holonym: atom

Comeronyms: proton, neutron

(physics) The subatomic particle having a negative charge and orbiting the nucleus; the flow of electrons in a conductor constitutes electricity.

elektron

the negatively charged subatomic particles that orbit atoms


tau

Hospital Brothers of Saint Anthony
Trần Thanh Vân

From Middle English tau, taue, from Latin tau, from Ancient Greek ταῦ (taû) and Hebrew תָּו (tav).
Sense 6 (“mathematical constant equal to 2π”) was used by Joseph M. Lindenberg in 1991, and popularized by the American educator and entrepreneur Michael Hartl in a 2010 paper which explains that τ resembles π; and that τ is the Greek equivalent of t, the first letter of turn, and 2π corresponds to one turn of a circle with a radius of one unit.
Sense 8.1 (“short for tau lepton or tau particle”) was coined by the American physicist Martin Lewis Perl (1927–2014) after the first letter of Ancient Greek τρίτον (tríton, “third”), since the tau lepton or tauon was the third charged lepton discovered.

sequence box

Ancient Greek Alphabet

<big>Τ τ </big>
Ancient Greek: ταῦ

croix en tau

Saint Anthony’s cross — see also Saint Anthony's cross

Short for tau lepton or tau particle (“an unstable elementary particle which is a type of lepton, having a mass almost twice that of a proton, a negative charge, and a spin of ½; it decays into hadrons (usually pions) or other leptons, and neutrinos; a tauon”).


quark

Finnegans Wake
James Joyce
Quark#Etymology

Coined by American physicist Murray Gell-Mann in 1963. The literary connection to James Joyce's Finnegans Wake was asserted later; see the Quark Wikipedia article.

coin

There were also particles no one had predicted that just appeared. Five of them […, i]n order of increasing modernity, […] are the neutrino, the pi meson, the antiproton, the quark and the Higgs boson.

2012 March-April, Jeremy Bernstein, “A Palette of Particles”, in American Scientist, volume 100, number 2, page 146:

(physics) In the Standard Model, an elementary subatomic particle that forms matter. They combine to form hadrons, such as protons and neutrons.

كِوَرْكٌ

(physics) In the Standard Model, an elementary subatomic particle which forms matter


muon

Contraction of the earlier term mu-meson; the particle has now been recategorised as a lepton. Coined by Italian physicist Enrico Fermi in 1951 in his book Elementary Particles.

The μ-meson of Powell (called here muon) is instead a disintegration product of the pion, only weakly linked to the nucleons and therefore of little importance in the explanation of nuclear forces.

1951, Enrico Fermi, Elementary Particles:

The spectrum of electrons arising from the decay of the negative mu meson has been determined. The muons are arrested in the gas of a high pressure hydrogen filled diffusion cloud chamber.

1955 March, CP Sargent, “Diffusion Cloud-Chamber Study of Very Slow Mesons”, in Physical Review:

The data comes from experiments at the Fermilab US particle accelerator facility, which explored how subatomic particles called muons – similar to electrons but about 200 times heavier – move in a magnetic field.

2023 August 11, Nicola Davis, “Scientists may be on brink of discovering fifth force of nature”, in The Guardian:

(physics) An unstable elementary particle in the lepton family, having similar properties to the electron but with a mass 207 times greater.

մյուոն

an unstable elementary particle in the lepton family


neutrino

Coined by Italian physicist Enrico Fermi in 1933 from neutron + the Italian diminutive suffix -ino.

But researchers at the CERN lab near Geneva claim they have recorded neutrinos, a type of tiny particle, travelling faster than the barrier of 186,282 miles (299,792 kilometres) per second.

2011 September 22, Nick Collins, “Speed of light 'broken' by scientists”, in Daily Telegraph:

An elementary particle that is classified as a lepton, and has an extremely small but nonzero mass and no electric charge. It interacts with the surroundings only via the weak force or gravitation, making it very difficult to detect.

neutrino

An elementary particle with extremely small mass and no electric charge


fermion

From Fermi + -on. Named after Italian-American physicist Enrico Fermi. Coined by English physicist Paul Dirac in 1945 in a lecture titled "Developments in Atomic Theory".

فرميون

particle with totally antisymmetric composite quantum states

The fermions treated by the Standard Model are the (composite) baryons and the (elementary) leptons and quarks.

According to the spin–statistics theorem, the wavefunction of a system of identical fermions (particles of half-integer spin) is antisymmetric under the operation of swapping any two particles.

A remarkable feature of lattice regularization is the appearance of several fermion species per fermion field in the lattice action.

1994, István Montvay, Gernot Münster, Quantum Fields on a Lattice, Cambridge University Press, page 208:

For 2D systems, going beyond first order pertu[r]bative calculations, we show that the second harmonic of the current is strongly suppressed in the case of spinless fermion models but significantly enhanced for the Hubbard model.

1996, Georges Bouzerar, Didier Poilblanc, “Persistent Currents in Interacting Electronic Systems”, in T. Martin, G. Montambaux, J. Trân Thanh Vân, editors, Correlated Fermions and Transport in Mesoscopic Systems, Editions Frontieres, page 149:

It is not known whether the Higgs mechanism is the true source for the masses of the fundamental fermions.

1996, Georg G. Raffelt, Stars as Laboratories for Fundamental Physics, University of Chicago Press, page 253:

The snapshots were taken by MIT physicists and are the first images that directly capture the pairing of fermions — a major class of particles that includes electrons, as well as protons, neutrons, and certain types of atoms.

2023 July 6, Jennifer Chu, “MIT physicists generate the first snapshots of fermion pairs”, in MIT News:

Pauli exclusion principle
Pauli exclusion principle

(particle physics, Standard Model) Any elementary or composite particle that has half-integer spin and thus obeys Fermi–Dirac statistics and the Pauli exclusion principle (equivalently, a particle for which the wavefunction of any system of identical such particles changes sign whenever two are swapped); a baryon, a lepton or a quark;

Any elementary or composite particle that has half-integer spin and thus obeys Fermi–Dirac statistics and the Pauli exclusion principle (equivalently, a particle for which the wavefunction of any system of identical such particles changes sign whenever two are swapped); a baryon, a lepton or a quark;
(slightly more loosely) any such particle or any composite particle composed of fermions.


lepton

From Ancient Greek λεπτός (leptós) + -on. Coined by Dutch-American physicist Abraham Pais in 1947.

In the present paper we deal with the second order radiative correction to the beta disintegration of nucleon, assuming the Fermi's interaction between necleon and lepton fields, and show that there appears such an ultraviolet divergence as can not be removed by the procedure of renormalization of mass and coupling constant, so far as a single type of coupling is assumed for the decay Hamiltonian.

1950, Tadao Nakano, “Radiative Correction to Decay Processes”, in Progress of Theoretical Physics, volume 5, number 6:

strong nuclear force
strong nuclear force

(particle physics) An elementary particle that has a spin of 1/2 (i.e., is a fermion) and does not interact via the strong nuclear force; examples include the electron, the muon, the neutrino and the tauon.


electron neutrino

en-noun

electron neutrino (plural electron neutrinos)

A leptonic elementary particle, having near-zero mass and no charge


muon neutrino

Here, OPERA's scientists told their colleagues in Kyoto that they have spotted a so-called muon-neutrino (of the sort whipped up at CERN) turn into another, tau-flavoured one.

2012 June 8, “Back to the future”, in The Economist:

A leptonic elementary particle having about half the mass of an electron and no charge.


beauty quark

(physics, dated) Synonym of bottom quark.


tau neutrino

A leptonic elementary particle having a mass 60 times that of the electron and no charge


tauon

From tau + -on, tau short for Ancient Greek τρίτος (trítos, “third”), being the third lepton discovered.

An unstable elementary particle which is a type of lepton, having a mass almost twice that of a proton, a negative charge, and a spin of ½; it decays into hadrons (usually pions) or other leptons, and neutrinos.


down quark

(physics) A quark having a fractional electric charge of -1/3 and a mass of about 4 to 8 MeV.

A quark having a fractional electric charge of -1/3 and a mass of about 4 to 8 MeV.
Symbol: d


top quark

(physics) A quark having a fractional electric charge of +2/3 and a mass of about 178,000 MeV.

A quark having a fractional electric charge of +2/3 and a mass of about 178,000 MeV.
Symbol: t


bottom quark

(physics) A quark having a fractional electric charge of -1/3 and a mass of about 4,100 to 4,400 MeV.

A quark having a fractional electric charge of -1/3 and a mass of about 4,100 to 4,400 MeV.
Symbol: b


charm quark

(physics) A quark having a fractional electric charge of +2/3 and a mass of about 1150 to 1350 MeV.

A quark having a fractional electric charge of +2/3 and a mass of about 1150 to 1350 MeV.
Symbol: c


strange quark

(physics) A quark having a fractional electric charge of -1/3 and a mass of about 80 to 130 MeV.

A quark having a fractional electric charge of -1/3 and a mass of about 80 to 130 MeV.
Symbol: s


up quark

(physics) A quark having a fractional electric charge of +2/3 and a mass of about 1.5 to 4 MeV.

A quark having a fractional electric charge of +2/3 and a mass of about 1.5 to 4 MeV.
Symbol: u


anti-strange quark

anti-strange quark (plural anti-strange quarks)

(physics) The antiquark corresponding to the strange quark.

outo-antikvarkki

the antiquark corresponding to the strange quark


anti-down quark

anti-down quark (plural anti-down quarks)

(physics) The antiquark corresponding to the down quark.

alas-antikvarkki

the antiquark corresponding to the down quark


anti-top quark

(physics) the antiquark corresponding to the top quark.


anti-bottom quark

anti-bottom quark (plural anti-bottom quarks)

(physics) The antiquark corresponding to the bottom quark.

pohja-antikvarkki

the antiquark corresponding to the bottom quark


anti-up quark

(physics) The antiquark corresponding to the up quark.

ylös-antikvarkki

the antiquark corresponding to the up quark


squark

(physics) A hypothetical supersymmetric counterpart to a quark, having a spin of zero instead of one-half.


stop squark

(physics) A squark which is the hypothetical supersymmetric partner of a top quark.

A squark which is the hypothetical supersymmetric partner of a top quark.
Symbol: ̃t