Editing Xenon (section)

=== Nuclear fission ===
[[Xenon-135]] is a notable [[neutron poison]] with a high [[fission product yield]]. As it is relatively short lived, it decays at the same rate it is produced during ''steady'' operation of a nuclear reactor. However, if power is reduced or the reactor is [[scram]]med, less xenon is destroyed than is produced from the beta decay of its [[parent nuclide]]s. This phenomenon called [[xenon poisoning]] can cause significant problems in restarting a reactor after a scram or increasing power after it had been reduced and it was one of several contributing factors in the [[Chernobyl nuclear accident]].<ref>{{cite web
| url   = http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/xenon.html
| title = "Xenon Poisoning" or Neutron Absorption in Reactors
}}</ref><ref>{{cite web
| url   = https://world-nuclear.org/information-library/safety-and-security/safety-of-plants/appendices/chernobyl-accident-appendix-1-sequence-of-events.aspx
| title = Chernobyl Appendix 1: Sequence of Events – World Nuclear Association
}}</ref>

Stable or extremely long lived isotopes of xenon are also produced in appreciable quantities in nuclear fission. Xenon-136 is produced both as a fission product and when xenon-135 undergoes [[neutron capture]] before it can decay. The ratio of xenon-136 to xenon-135 (or its decay products) can give hints as to the power history of a given reactor or identify a nuclear explosion, as xenon-135 is mostly produced by successive beta decays of more neutron-rich fission products. These short-lived nuclides do not share its neutron-absorbing prowess, and so absorb fewer neutrons during the brief moment of a nuclear explosion, lowering the ratio of mass-136 to mass-135 products.<ref>{{Cite journal
| doi        = 10.1016/j.net.2016.04.006
| title      = Development of Industrial-Scale Fission 99Mo Production Process Using Low Enriched Uranium Target
| year       = 2016
| last1      = Lee
| first1     = Seung-Kon
| last2      = Beyer
| first2     = Gerd J.
| last3      = Lee
| first3     = Jun Sig
| journal    = Nuclear Engineering and Technology
| volume     = 48
| issue      = 3
| pages      = 613–623
| doi-access = free
}}</ref>

The stable isotope xenon-132 has a fission product yield of over 4% in the [[thermal neutron]] fission of {{chem|235|U}} which means that stable or nearly stable xenon isotopes have a higher mass fraction in [[spent nuclear fuel]] (which is about 3% fission products) than it does in air. However, there is as of 2022 no commercial effort to extract xenon from spent fuel during [[nuclear reprocessing]].<ref>{{Cite web
| url   = https://news.mit.edu/2020/novel-gas-capture-approach-advances-nuclear-fuel-management-0724
| title = Novel gas-capture approach advances nuclear fuel management
| date  = July 24, 2020
}}</ref><ref>{{Cite web
| url   = https://energyfromthorium.com/2010/06/22/whats-in-spent-nuclear-fuel-after-20-yrs/
| title = What's in Spent Nuclear Fuel? (After 20 yrs) – Energy from Thorium
| date  = June 22, 2010
}}</ref>