Editing Hypernucleus (section)

=== ΛΛ and Ξ hypernuclei ===
Hypernuclei containing two Λ baryons have been made. However, such hypernuclei are much harder to produce due to containing two strange quarks and, as of 2016, only seven candidate ΛΛ hypernuclei have been observed.{{sfn|Gal|Hungerford|Millener|2016|p=41}} Like the Λ–nucleon interaction, empirical and theoretical models predict that the Λ–Λ interaction is mildly attractive.{{sfn|Tolos|Fabbietti|2020|pp=43–45,59}}<ref>{{cite journal |author=ALICE Collaboration|title=Study of the Λ–Λ interaction with femtoscopy correlations in pp and p–Pb collisions at the LHC |journal=Physics Letters B |date=10 October 2019 |volume=797 |pages=134822 |doi=10.1016/j.physletb.2019.134822 |arxiv=1905.07209 |bibcode=2019PhLB..79734822A |s2cid=161048820 |url=https://www.sciencedirect.com/science/article/pii/S0370269319305362 |language=en |issn=0370-2693}}</ref>

Hypernuclei containing a Ξ baryon are known.{{citation needed|date=January 2024}} Empirical studies and theoretical models indicate that the Ξ<sup>–</sup>–proton interaction is attractive, but weaker than the Λ–nucleon interaction.{{sfn|Tolos|Fabbietti|2020|pp=43–45,59}} Like the Σ<sup>–</sup> and other negatively charged particles, the Ξ<sup>–</sup> can also form an exotic atom. When a Ξ<sup>–</sup> is bound in an exotic atom or a hypernucleus, it quickly decays to a ΛΛ hypernucleus or to two Λ hypernuclei by exchanging a strange quark with a proton, which releases about 29&nbsp;MeV of energy in free space:{{efn|name=qvalue|The initial proton and Ξ<sup>–</sup> have respective masses of approximately 938.3 and 1321.7&nbsp;MeV, while the outgoing Λ's are each about 1115.7&nbsp;MeV;<ref>{{cite journal |last1=Workman |first1=R L |last2=Burkert |first2=V D |last3=Crede |first3=V |last4=Klempt |first4=E |last5=Thoma |first5=U |last6=Tiator |first6=L |display-authors=1|collaboration=Particle Data Group|title=Review of Particle Physics |journal=Progress of Theoretical and Experimental Physics |date=8 August 2022 |volume=2022 |issue=8 |page=083C01 |doi=10.1093/ptep/ptac097|doi-access=free |hdl=11585/900713 |hdl-access=free }}</ref> the energy that is released is equal to the amount of mass that is lost (times ''c''<sup>2</sup>).}}
:Ξ<sup>−</sup> + p → Λ + Λ<ref name="JPARC E07"/>{{sfn|Gal|Hungerford|Millener|2016|pp=16,43}}{{sfn|Tolos|Fabbietti|2020|p=53}}