Editing List of particles (section)

== Standard Model elementary particles ==
{{Main|Elementary particle}}
{{hatnote|See [[Standard Model]] for the current consensus theory of these particles.}}
Elementary particles are particles with no measurable internal structure; that is, it is unknown whether they are composed of other particles.<ref name="PFIp1-3">
{{cite book |author1=Braibant |first=Sylvie |url=https://books.google.com/books?id=e8YUUG2pGeIC&pg=PA1 |title=Particles and Fundamental Interactions: An Introduction to Particle Physics |author2=Giacomelli |first2=Giorgio |author3=Spurio |first3=Maurizio |publisher=[[Springer (publisher)|Springer]] |year=2012 |isbn=978-94-007-2463-1 |edition=1st |pages=1}}</ref> They are the fundamental objects of [[quantum field theory]]. Many families and sub-families of elementary particles exist. Elementary particles are classified according to their [[Spin (physics)|spin]]. [[Fermion]]s have half-integer spin while [[boson]]s have integer spin. All the elementary particles of the [[Standard Model]] have been experimentally observed, including the [[Higgs boson]] in 2012.<ref>{{Cite journal |last1=Khachatryan |first1=V. |display-authors=etal |collaboration=CMS Collaboration |year=2012 |title=Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC |journal=[[Physics Letters B]] |volume=716 |issue=2012 |pages=30–61 |arxiv=1207.7235 |bibcode= 2012PhLB..716...30C|doi=10.1016/j.physletb.2012.08.021 }}</ref><ref>{{Cite journal |last1=Abajyan |first1=T. |collaboration=ATLAS Collaboration |display-authors=etal |title=Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC |journal=[[Physics Letters B]] |volume=716 |issue=2012 |pages=1–29 |year=2012 |arxiv=1207.7214  |bibcode= 2012PhLB..716....1A|doi=10.1016/j.physletb.2012.08.020|s2cid=119169617 }}</ref> Many other hypothetical elementary particles, such as the [[graviton]], have been proposed, but not observed experimentally.
{{Elementary particles|SM=yes}}

=== Fermions ===
[[Fermion]]s are one of the two fundamental classes of particles, the other being [[boson]]s. Fermion particles are described by [[Fermi–Dirac statistics]] and have [[quantum numbers]] described by the [[Pauli exclusion principle]]. They include the [[quarks]] and [[leptons]], as well as any [[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 elementary fermions this is {{sfrac|1|2}}''ħ''. All known fermions except [[neutrinos]], are also [[Dirac fermion]]s; that is, each known fermion has its own distinct [[antiparticle]]. It is not known whether the [[neutrino]] is a [[Dirac fermion]] or a [[Majorana fermion]].<ref>{{cite arXiv |eprint=1012.4469|last1=Kayser|first1=Boris|title=Two Questions About Neutrinos|class=hep-ph|year=2010}}</ref> Fermions are the basic building blocks of all [[matter]]. They are classified according to whether they interact via the [[strong interaction]] or not. In the Standard Model, there are 12 types of elementary fermions: six [[quark]]s and six [[lepton]]s.

==== Quarks ====
[[Quark]]s are the fundamental constituents of [[hadron]]s and interact via the [[strong force]]. Quarks are the only known carriers of [[fractional charge]], but because they combine in groups of three quarks (baryons) or in pairs of one quark and one [[antiquark]] (mesons), only integer charge is observed in nature. Their respective [[antiparticle]]s are the [[antiquark]]s, which are identical except that they carry the opposite electric charge (for example the up quark carries charge +{{sfrac|2|3}}''e'', while the up antiquark carries charge −{{sfrac|2|3}}''e''), color charge, and baryon number. There are six [[flavor (particle physics)|flavors]] of quarks; the three positively charged quarks are called "up-type quarks" while the three negatively charged quarks are called "down-type quarks".

{|class="wikitable sortable" style="margin:1em auto; text-align:center"
|+Quarks
|-
! Generation !! Name !! Symbol !! Antiparticle !! Spin{{br}}{{bracket|[[reduced Planck constant|''ħ'']]}} !! Charge{{br}}{{bracket|[[elementary charge|''e'']]}} !! data-sort-type="number"|Mass<ref name="PDG Light Quarks">{{cite web |title=Light quarks (u, d, s)|url=https://pdglive.lbl.gov/Particle.action?node=Q123&init=0 |website=pdglive.lbl.gov |publisher=Particle Data Group |access-date=24 September 2024}}</ref><ref name="PDG Charm Quark">{{cite web |title=c quark|url=https://pdglive.lbl.gov/Particle.action?node=Q004&init=0 |website=pdglive.lbl.gov |publisher=Particle Data Group |access-date=24 September 2024}}</ref><ref name="PDG Bottom Quark">{{cite web |title=b quark|url=https://pdglive.lbl.gov/Particle.action?node=Q005&init=0 |website=pdglive.lbl.gov |publisher=Particle Data Group |access-date=24 September 2024}}</ref><ref name="PDG Top Quark">{{cite web |title=t quark|url=https://pdglive.lbl.gov/Particle.action?node=Q007&init=0 |website=pdglive.lbl.gov |publisher=Particle Data Group |access-date=24 September 2024}}</ref>{{br}}{{bracket|[[electronvolt|MeV]]/[[speed of light|''c'']]<sup>2</sup>}}
|-
|rowspan=2| 1
| [[Up quark|up]] || u || {{Subatomic particle|up antiquark}}
|data-sort-value="1"|{{sfrac|1|2}} || +{{sfrac|2|3}} || {{val|2.16|0.07}}
|-
| [[Down quark|down]] || d || {{Subatomic particle|down antiquark}}
|data-sort-value="2"|{{sfrac|1|2}} || −{{sfrac|1|3}} || {{val|4.70|0.07}}
|-
|rowspan=2| 2
| [[Charm quark|charm]] || c || {{Subatomic particle|charm antiquark}}
|data-sort-value="3"|{{sfrac|1|2}} || +{{sfrac|2|3}} || {{val|1,273.0|4.6}}
|-
| [[Strange quark|strange]] || s || {{Subatomic particle|strange antiquark}}
|data-sort-value="4"|{{sfrac|1|2}} || −{{sfrac|1|3}} || {{val|93.5|0.8}}
|-
|rowspan=2| 3
| [[Top quark|top]] || t || {{Subatomic particle|top antiquark}}
|data-sort-value="5"|{{sfrac|1|2}} || +{{sfrac|2|3}} || {{val|172570|290}}
|-
| [[Bottom quark|bottom]] || b || {{Subatomic particle|bottom antiquark}}
|data-sort-value="6"|{{sfrac|1|2}} || −{{sfrac|1|3}} || {{val|4,183|7}}
|}

==== Leptons ====
[[Lepton]]s do not interact via the [[strong interaction]]. Their respective [[antiparticle]]s are the [[antilepton]]s, which are identical, except that they carry the opposite electric charge and lepton number. The antiparticle of an [[electron]] is an antielectron, which is almost always called a "[[positron]]" for historical reasons. There are six leptons in total; the three charged leptons are called "electron-like leptons", while the neutral leptons are called "[[neutrino]]s". Neutrinos are known to [[neutrino oscillation|oscillate]], so that neutrinos of definite [[flavour (particle physics)|flavor]] do not have definite mass: instead, they exist in a superposition of mass [[eigenstate]]s. The hypothetical heavy right-handed neutrino, called a "[[sterile neutrino]]", has been omitted.

{|class="wikitable sortable" style="margin:1em auto; text-align:center"
|+Leptons
|-
! Generation !! Name !! Symbol !! Antiparticle !! Spin{{br}}{{bracket|[[reduced Planck constant|''ħ'']]}} !! Charge{{br}}{{bracket|[[elementary charge|''e'']]}} !! Mass<ref name="PDG2016">{{cite journal |title=Review of Particle Physics |author=Particle Data Group |journal=Chinese Physics C |volume=40 |issue=10|pages=100001 |year=2016 |doi=10.1088/1674-1137/40/10/100001 |bibcode=2016ChPhC..40j0001P |hdl=1983/c6dc3926-daee-4d0e-9149-5ff3a8120574 |s2cid=125766528 |url=https://cds.cern.ch/record/2241948|hdl-access=free }}</ref>{{br}}{{bracket|[[electronvolt|MeV]]/[[speed of light|''c'']]<sup>2</sup>}}
|-
|rowspan=2| 1
| [[electron]] || {{Subatomic particle|electron}} || {{Subatomic particle|positron}}
|data-sort-value="4"| {{sfrac| 1 |2}} || −1 || 0.511{{refn|group=note|
A precise value of the electron mass is {{physconst|mec2_MeV|unit={{val|u=MeV/c2}}.}}
}}
|-
| [[electron neutrino]] || {{math|{{Subatomic particle|electron neutrino}}}} || {{math|{{Subatomic particle|electron antineutrino}}}}
|data-sort-value="1"| {{sfrac| 1 |2}} || &nbsp;&thinsp;0 || {{nowrap| < 0.0000022}}
|-
|rowspan=2| 2
| [[muon]] || {{math|{{Subatomic particle|muon}}}} || {{math|{{Subatomic particle|antimuon}}}}
|data-sort-value="5"| {{sfrac| 1 |2}} || −1 || 105.7{{refn|group=note|
A precise value of the muon mass is {{physconst|mmuc2_MeV|unit={{val|u=MeV/c2}}.}}
}}
|-
| [[muon neutrino]] || {{math|{{Subatomic particle|muon neutrino}}}} || {{math|{{Subatomic particle|muon antineutrino}}}}
|data-sort-value="2"| {{sfrac| 1 |2}} || &nbsp;&thinsp;0 || {{nowrap| < 0.170}}
|-
|rowspan=2| 3
| [[Tau (particle)|tau]] || {{math|{{Subatomic particle|tau}}}} || {{math|{{Subatomic particle|antitau}}}}
|data-sort-value="3"| {{sfrac| 1 |2}} || −1 || {{val|1,776.86|0.12}}
|-
| [[tau neutrino]] || {{math|{{Subatomic particle|tau neutrino}}}} || {{math|{{Subatomic particle|tau antineutrino}}}}
|data-sort-value="6"| {{sfrac| 1 |2}} || &nbsp;&thinsp;0 || {{nowrap| < 15.5}}
|}
{{reflist|group=note}}

=== Bosons ===
[[Boson]]s are one of the two fundamental particles having integral spinclasses of particles, the other being [[fermion]]s. Bosons are characterized by [[Bose–Einstein statistics]] and all have integer spins. Bosons may be either elementary, like [[photons]] and [[gluons]], or composite, like [[mesons]].

According to the [[Standard Model]], the elementary bosons are:

{| class="wikitable sortable" style="margin:1em auto; align: center; text-align: center;"
! Name !! Symbol !! Antiparticle !! Spin{{br}}{{bracket|[[reduced Planck constant|''ħ'']]}} !! Charge{{br}}{{bracket|[[elementary charge|''e'']]}} !! Mass<ref name="PDG2016" />{{br}}{{bracket|[[electronvolt|GeV]]/[[speed of light|''c'']]<sup>2</sup>}} !! Interaction mediated !!Observed
|-
| [[photon]] || {{math|γ}} || self || 1 || 0 || 0 || [[electromagnetism]] || {{yes|yes}}
|-
| [[W and Z bosons|W boson]] || {{Subatomic particle|W Boson-}} || {{Subatomic particle|W Boson+}} || 1 || ±1 || {{val|80.385|0.015}} || [[weak interaction]] || {{yes|yes}}
|-
| [[W and Z bosons|Z boson]] || {{Subatomic particle|Z Boson}} || self || 1 || 0 || {{val|91.1875|0.0021}} || [[weak interaction]] || {{yes|yes}}
|-
| [[gluon]] || {{Subatomic particle|Gluon}} || self || 1 || 0 || 0 || [[strong interaction]] || {{yes|yes}}
|-
| [[Higgs boson]] || {{Subatomic particle|Higgs boson}} || self || 0 || 0 ||{{val|125.09|0.24}} || [[mass]] || {{yes|yes}}
|}

The [[Higgs boson]] is postulated by the [[electroweak theory]] primarily to explain the origin of [[Mass|particle masses]]. In a process known as the "[[Higgs mechanism]]", the Higgs boson and the other gauge bosons in the Standard Model acquire mass via [[spontaneous symmetry breaking]] of the SU(2) gauge symmetry. The [[Minimal Supersymmetric Standard Model]] (MSSM) predicts several Higgs bosons. On 4 July 2012, the discovery of a new particle with a mass between {{val|125|and|127|u=GeV/c2}} was announced; physicists suspected that it was the Higgs boson. Since then, the particle has been shown to behave, interact, and decay in many of the ways predicted for Higgs particles by the Standard Model, as well as having even parity and zero spin, two fundamental attributes of a Higgs boson. This also means it is the first elementary scalar particle discovered in nature.

Elementary bosons responsible for the four [[fundamental force]]s of nature are called [[Force carrier|force particles]] ([[gauge boson]]s). The [[strong interaction]] is mediated by the [[gluon]], the [[weak interaction]] is mediated by the W and Z bosons, [[electromagnetism]] by the photon, and [[gravity]] by the graviton, which is still hypothetical.