Editing Electron (section)

== Characterization ==

Electrons belong to the first [[generation (particle physics)|generation]] of the [[lepton]] particle family,<ref name="curtis74">
{{cite book
 | last = Curtis | first = L.J.
 | year = 2003
 | title = Atomic Structure and Lifetimes: A conceptual approach
 | page = 74
 | publisher = Cambridge University Press
 | isbn = 978-0-521-53635-6
 | url = https://books.google.com/books?id=KmwCsuvxClAC&pg=PA74
 | access-date = 2020-08-25 | url-status = live
 | archive-url = https://web.archive.org/web/20200316220442/https://books.google.com/books?id=KmwCsuvxClAC&pg=PA74
 | archive-date = 2020-03-16
}}
</ref> elementary particles that do not feel the strong nuclear force, and only interact through the weak and electromagnetic forces. Electrons are generally thought to be [[elementary particle]]s because they have no known components or substructure.<ref name="prl50" /> An electron's [[Invariant mass|mass]] is approximately [[Proton-to-electron mass ratio|{{sfrac|1|1836}}]] that of a [[proton]].<ref name="nist_codata_mu" /> [[Quantum mechanics|Quantum mechanical]] properties of the electron include an intrinsic [[angular momentum]] ([[spin (physics)|spin]]) of half the [[reduced Planck constant]], i.e. {{sfrac|''ħ''|2}}. Being [[fermion]]s, no two electrons can occupy the same [[quantum state]], according to the [[Pauli exclusion principle]].<ref name=curtis74/> Like all elementary particles, electrons exhibit properties of [[wave–particle duality|both particles and waves]]: They can collide with other particles and can be [[electron diffraction|diffracted]] like light. The [[#Quantum properties|wave properties of electrons]] are easier to observe with experiments than those of other particles like [[neutron]]s and protons because electrons have a lower mass and hence a longer [[de Broglie wavelength]] for a given energy.

Electrons play an essential role in numerous [[physics|physical]] phenomena, such as [[electricity]], [[magnetism]], [[chemistry]], and [[thermal conductivity]]; they also participate in [[gravitational wave|gravitational]], [[Lorentz force|electromagnetic]], and [[weak interaction]]s.<ref name="anastopoulos1" /> Since an electron has charge, it has a surrounding [[electric field]]; if that electron is moving relative to an observer, the observer will observe it to generate a [[magnetic field]]. Electromagnetic fields produced from other sources will affect the motion of an electron according to the [[Lorentz force law]]. Electrons radiate or absorb energy in the form of [[photon]]s when they are accelerated.

Laboratory instruments are capable of trapping individual electrons as well as [[Plasma (physics)|electron plasma]] by the use of electromagnetic fields. Special [[telescope]]s can detect electron plasma in outer space. Electrons are involved in many applications, such as [[tribology]] or frictional charging, electrolysis, electrochemistry, battery technologies, [[electronics]], [[Electron beam welding|welding]], [[cathode-ray tube]]s, photoelectricity, photovoltaic solar panels, [[electron microscope]]s, [[radiation therapy]], [[Free-electron laser|lasers]], [[gaseous ionization detectors]], and [[particle accelerator]]s.

Interactions involving electrons with other subatomic particles are of interest in fields such as [[chemistry]] and [[nuclear physics]]. [[Atoms]] are composed of positive [[proton]]s within [[atomic nucleus|atomic nuclei]] and the negative electrons without, held together by [[Coulomb's law|Coulomb force]] interaction. Ionization state (differences in the proportions of negative electrons versus positive nuclei) or sharing of the electrons between two or more atoms are the main causes of [[chemical bond]]ing.<ref name=Pauling />

Electrons participate in [[nuclear reaction]]s, such as [[stellar nucleosynthesis|nucleosynthesis in stars]], where they are known as [[beta particle]]s. Electrons can be created through [[beta decay]] of [[Radionuclide|radioactive isotopes]] and in high-energy collisions, for instance, when [[cosmic ray]]s enter the atmosphere.  The [[antiparticle]] of the electron is called the [[positron]]; it is identical to the electron, except that it carries electrical [[charge (physics)|charge]] of the opposite sign. When an [[Electron–positron annihilation|electron collides with a positron]], both particles can be [[annihilation|annihilated]], producing [[gamma ray]] [[photon]]s.