Editing Nuclear fusion (section)

{{Short description|Process of combining atomic nuclei}}
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{{About|the nuclear reaction|its use in producing energy|Fusion power|the journal|Nuclear Fusion (journal){{!}}''Nuclear Fusion'' (journal)|the song|Nuclear Fusion (song)}}
{{Distinguish|Nuclear fission}}
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# [[The Sun]], powered by the [[proton–proton chain|proton–proton]] fusion chain
# [[Antares]], a star massive enough for [[silicon burning]]
# [[Operation Dominic|Dominic Housatonic]], largest fusion yield from a US nuclear test
# [[Greenhouse George]]'s Cylinder device, the first artificial thermonuclear fusion experiment
# [[Ivy Mike]]'s Sausage device, the first [[Teller–Ulam]] bomb
# Fusion plasma in China's [[Experimental Advanced Superconducting Tokamak]]
# Implosion lasers firing at [[National Ignition Facility]], the world's largest [[inertial confinement fusion]] experiment
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{{Nuclear physics}}

'''Nuclear fusion''' is a [[nuclear reaction|reaction]] in which two or more [[atomic nuclei]] combine to form a larger nuclei, nuclei/[[neutrons|neutron]] by-products. The difference in mass between the reactants and products is manifested as either the release or [[absorption (electromagnetic radiation)|absorption]] of [[energy]]. This difference in mass arises as a result of the difference in [[nuclear binding energy]] between the atomic nuclei before and after the fusion reaction. Nuclear fusion is the process that powers all active [[stars]], via many [[Stellar nucleosynthesis|reaction pathways]].

Fusion processes require an extremely large [[Lawson criterion|triple product]] of temperature, density, and confinement time. These conditions occur only in [[Stellar core|stellar cores]], advanced [[Nuclear weapon design|nuclear weapons]], and are approached in [[List of fusion experiments|fusion power experiments]].

A nuclear fusion process that produces atomic nuclei lighter than [[nickel-62]] is generally [[exothermic]], due to the positive gradient of the [[Nuclear binding energy#Nuclear binding energy curve|nuclear binding energy curve]]. The most fusible nuclei are among the lightest, especially [[deuterium]], [[tritium]], and [[helium-3]]. The opposite process, [[nuclear fission]], is most energetic for very heavy nuclei, especially the [[actinides]].

Applications of fusion include [[fusion power]], [[thermonuclear weapons]], [[Boosted fission weapon|boosted fission weapons]], [[Neutron source|neutron sources]], and [[superheavy element]] production.