Editing Hypernucleus (section)

== Similar species ==
===Kaonic nuclei===
The K<sup>–</sup> meson can orbit a nucleus in an exotic atom, such as in [[kaonic hydrogen]].<ref>{{cite journal |last1=Iwasaki |first1=M. |last2=Hayano |first2=R. S. |last3=Ito |first3=T. M. |last4=Nakamura |first4=S. N. |last5=Terada |first5=T. P. |last6=Gill |first6=D. R. |last7=Lee |first7=L. |last8=Olin |first8=A. |last9=Salomon |first9=M. |last10=Yen |first10=S. |last11=Bartlett |first11=K. |last12=Beer |first12=G. A. |last13=Mason |first13=G. |last14=Trayling |first14=G. |last15=Outa |first15=H. |last16=Taniguchi |first16=T. |last17=Yamashita |first17=Y. |last18=Seki |first18=R. |title=Observation of Kaonic Hydrogen K α X Rays |journal=Physical Review Letters |date=21 April 1997 |volume=78 |issue=16 |pages=3067–3069 |doi=10.1103/PhysRevLett.78.3067|bibcode=1997PhRvL..78.3067I }}</ref> Although the K<sup>–</sup>-proton strong interaction in kaonic hydrogen is repulsive,<ref>{{cite journal |last1=Bazzi |first1=M. |last2=Beer |first2=G. |last3=Bombelli |first3=L. |last4=Bragadireanu |first4=A.M. |last5=Cargnelli |first5=M. |last6=Corradi |first6=G. |last7=Curceanu (Petrascu) |first7=C. |last8=dʼUffizi |first8=A. |last9=Fiorini |first9=C. |last10=Frizzi |first10=T. |last11=Ghio |first11=F. |last12=Girolami |first12=B. |last13=Guaraldo |first13=C. |last14=Hayano |first14=R.S. |last15=Iliescu |first15=M. |last16=Ishiwatari |first16=T. |last17=Iwasaki |first17=M. |last18=Kienle |first18=P. |last19=Levi Sandri |first19=P. |last20=Longoni |first20=A. |last21=Lucherini |first21=V. |last22=Marton |first22=J. |last23=Okada |first23=S. |last24=Pietreanu |first24=D. |last25=Ponta |first25=T. |last26=Rizzo |first26=A. |last27=Romero Vidal |first27=A. |last28=Scordo |first28=A. |last29=Shi |first29=H. |last30=Sirghi |first30=D.L. |last31=Sirghi |first31=F. |last32=Tatsuno |first32=H. |last33=Tudorache |first33=A. |last34=Tudorache |first34=V. |last35=Vazquez Doce |first35=O. |last36=Widmann |first36=E. |last37=Zmeskal |first37=J. |title=A new measurement of kaonic hydrogen X-rays |journal=Physics Letters B |date=October 2011 |volume=704 |issue=3 |pages=113–117 |doi=10.1016/j.physletb.2011.09.011|arxiv=1105.3090|bibcode=2011PhLB..704..113S |s2cid=118473154 }}</ref> the K<sup>–</sup>–nucleus interaction is attractive for larger systems, so this meson can enter a strongly bound state closely related to a hypernucleus;<ref name="Feliciello"/> in particular, the K<sup>–</sup>–proton–proton system is experimentally known and more tightly bound than a normal nucleus.<ref>{{cite journal |last1=Sakuma |first1=F. |last2=Ajimura |first2=S. |last3=Akaishi |first3=T. |last4=Asano |first4=H. |last5=Bazzi |first5=M. |last6=Beer |first6=G. |last7=Bhang |first7=H. |last8=Bragadireanu |first8=M. |last9=Buehler |first9=P. |last10=Busso |first10=L. |last11=Cargnelli |first11=M. |last12=Choi |first12=S. |last13=Clozza |first13=A. |last14=Curceanu |first14=C. |last15=Enomoto |first15=S. |last16=Fujioka |first16=H. |last17=Fujiwara |first17=Y. |last18=Fukuda |first18=T. |last19=Guaraldo |first19=C. |last20=Hashimoto |first20=T. |last21=Hayano |first21=R. S. |last22=Hiraiwa |first22=T. |last23=Iio |first23=M. |last24=Iliescu |first24=M. |last25=Inoue |first25=K. |last26=Ishiguro |first26=Y. |last27=Ishikawa |first27=T. |last28=Ishimoto |first28=S. |last29=Itahashi |first29=K. |last30=Iwasaki |first30=M. |last31=Iwai |first31=M. |last32=Kanno |first32=K. |last33=Kato |first33=K. |last34=Kato |first34=Y. |last35=Kawasaki |first35=S. |last36=Kienle |first36=P. |last37=Kou |first37=H. |last38=Ma |first38=Y. |last39=Marton |first39=J. |last40=Matsuda |first40=Y. |last41=Miliucci |first41=M. |last42=Mizoi |first42=Y. |last43=Morra |first43=O. |last44=Murayama |first44=R. |last45=Nagae |first45=T. |last46=Noumi |first46=H. |last47=Ohnishi |first47=H. |last48=Okada |first48=S. |last49=Outa |first49=H. |last50=Ozawa |first50=K. |last51=Piscicchia |first51=K. |last52=Sada |first52=Y. |last53=Sakaguchi |first53=A. |last54=Sato |first54=M. |last55=Scordo |first55=A. |last56=Sekimoto |first56=M. |last57=Shi |first57=H. |last58=Shirotori |first58=K. |last59=Simon |first59=M. |last60=Sirghi |first60=D. |last61=Sirghi |first61=F. |last62=Suzuki |first62=S. |last63=Suzuki |first63=T. |last64=Tanida |first64=K. |last65=Tatsuno |first65=H. |last66=Tokuda |first66=M. |last67=Tomono |first67=D. |last68=Toyoda |first68=A. |last69=Tsukada |first69=K. |last70=Doce |first70=O. Vázquez |last71=Widmann |first71=E. |last72=Yamaga |first72=T. |last73=Yamazaki |first73=T. |last74=Yoshida |first74=C. |last75=Zhang |first75=Q. |last76=Zmeskal |first76=J.|display-authors= 1 |title=Recent Results and Future Prospects of Kaonic Nuclei at J-PARC |journal=Few-Body Systems |date=December 2021 |volume=62 |issue=4 |pages=103 |doi=10.1007/s00601-021-01692-3|arxiv=2110.03150 |bibcode=2021FBS....62..103S |s2cid=238419423 }}</ref>

===Charmed hypernuclei===
Nuclei containing a [[charm quark]] have been predicted theoretically since 1977,<ref>{{cite journal |last1=Dover |first1=C. B. |last2=Kahana |first2=S. H. |title=Possibility of Charmed Hypernuclei |journal=Physical Review Letters |date=12 December 1977 |volume=39 |issue=24 |pages=1506–1509 |doi=10.1103/PhysRevLett.39.1506|bibcode=1977PhRvL..39.1506D }}</ref> and are described as '''charmed hypernuclei''' despite the possible absence of strange quarks.<ref name="Gastão">{{cite book |last1=Krein |first1=Gastão |title=Central European Symposium on Thermophysics 2019 (Cest) |chapter=Charmed hypernuclei and nuclear-bound charmonia |date=2019 |volume=2133 |pages=020022 |doi=10.1063/1.5118390|s2cid=201510645 }}</ref> In particular, the lightest charmed baryons, the Λ<sub>c</sub> and Σ<sub>c</sub> baryons,{{efn|name=csub|The subscript ''c'' in the symbols for charmed baryons indicate that a strange quark in a hyperon is replaced with a charm quark; the superscript, if present, still represents the total charge of the baryon.}} are predicted to exist in bound states in charmed hypernuclei, and could be created in processes analogous to those used to make hypernuclei.<ref name="Gastão"/> The depth of the Λ<sub>c</sub> potential in nuclear matter is predicted to be 58&nbsp;MeV,<ref name="Gastão"/> but unlike Λ hypernuclei, larger hypernuclei containing the positively charged Λ<sub>c</sub> would be less stable than the corresponding Λ hypernuclei due to [[Coulomb repulsion]].<ref>{{cite journal |last1=Güven |first1=H. |last2=Bozkurt |first2=K. |last3=Khan |first3=E. |last4=Margueron |first4=J. |title=Ground state properties of charmed hypernuclei within a mean field approach |journal=Physical Review C |date=10 December 2021 |volume=104 |issue=6 |pages=064306 |doi=10.1103/PhysRevC.104.064306|arxiv=2106.04491 |bibcode=2021PhRvC.104f4306G |s2cid=235368356 }}</ref> The mass difference between the Λ<sub>c</sub> and the {{physics particle|Σ|TR=+|BR=c}} is too large for appreciable mixing of these baryons to occur in hypernuclei.<ref>{{cite journal |last1=Vidaña |first1=I. |last2=Ramos |first2=A. |last3=Jiménez-Tejero |first3=C. E. |title=Charmed nuclei within a microscopic many-body approach |journal=Physical Review C |date=23 April 2019 |volume=99 |issue=4 |pages=045208 |doi=10.1103/PhysRevC.99.045208|arxiv=1901.09644 |bibcode=2019PhRvC..99d5208V |s2cid=119100085 }}</ref> Weak decays of charmed hypernuclei have strong [[special relativity|relativistic]] corrections compared to those in ordinary hypernuclei, as the energy released in the decay process is comparable to the mass of the Λ baryon.<ref>{{cite journal |last1=Fontoura |first1=C E |last2=Krmpotić |first2=F |last3=Galeão |first3=A P |last4=Conti |first4=C De |last5=Krein |first5=G |title=Nonmesonic weak decay of charmed hypernuclei |journal=Journal of Physics G: Nuclear and Particle Physics |date=1 January 2018 |volume=45 |issue=1 |pages=015101 |doi=10.1088/1361-6471/aa982a|arxiv=1711.04579 |bibcode=2018JPhG...45a5101F |s2cid=119184293 }}</ref>

=== Antihypernuclei ===
In August 2024 the [[STAR collaboration|STAR Collaboration]] reported the observation of the heaviest [[antimatter]] nucleus known, antihyperhydrogen-4 <math>{}_{\bar{{\boldsymbol{\Lambda }}}}{}^{{\bf{4}}}\bar{{\bf{H}}}</math> consisting of one [[antiproton]], two [[Antineutron|antineutrons]] and an [[antihyperon]].<ref>{{Cite journal |last1=Abdulhamid |first1=M. I. |last2=Aboona |first2=B. E. |last3=Adam |first3=J. |last4=Adamczyk |first4=L. |last5=Adams |first5=J. R. |last6=Aggarwal |first6=I. |last7=Aggarwal |first7=M. M. |last8=Ahammed |first8=Z. |last9=Aschenauer |first9=E. C. |last10=Aslam |first10=S. |last11=Atchison |first11=J. |last12=Bairathi |first12=V. |last13=Cap |first13=J. G. Ball |last14=Barish |first14=K. |last15=Bellwied |first15=R. |date=2024-08-21 |title=Observation of the antimatter hypernucleus $${}_{\bar{{\boldsymbol{\Lambda }}<nowiki>}}{}^</nowiki>{{\bf{4}}}\bar{{\bf{H}}}$$ |url=https://www.nature.com/articles/s41586-024-07823-0 |journal=Nature |volume=632 |issue=8027 |language=en |pages=1026–1031 |doi=10.1038/s41586-024-07823-0 |pmid=39169195 |issn=1476-4687}}</ref><ref>{{Cite web |author1=Ben Turner |date=2024-08-21 |title=Heaviest antimatter particle ever discovered could hold secrets to our universe's origins |url=https://www.livescience.com/physics-mathematics/particle-physics/scientists-discover-the-heaviest-antimatter-particle-ever-and-it-could-hold-secrets-to-our-universes-origins |access-date=2024-08-26 |website=livescience.com |language=en}}</ref><ref>{{Cite web |last=Egede |first=Ulrik |date=2024-08-21 |title=Heaviest antimatter observation yet will fine-tune numbers for dark matter search |url=https://theconversation.com/heaviest-antimatter-observation-yet-will-fine-tune-numbers-for-dark-matter-search-237127 |access-date=2024-08-26 |website=The Conversation |language=en-US}}</ref> 

The anti-lambda hyperon <math>\bar{\Lambda }</math><ref>{{Cite journal |last1=Prowse |first1=D. J. |last2=Baldo-Ceolin |first2=M. |date=1958-09-01 |title=Anti-Lambda Hyperon |url=https://link.aps.org/doi/10.1103/PhysRevLett.1.179 |journal=Physical Review Letters |language=en |volume=1 |issue=5 |pages=179–180 |doi=10.1103/PhysRevLett.1.179 |bibcode=1958PhRvL...1..179P |issn=0031-9007|url-access=subscription }}</ref> and the antihypertriton <math>{}_{\bar{\Lambda }}{}^{3}\bar{{\rm{H}}}</math><ref>{{Cite journal |last1=The STAR Collaboration |last2=Abelev |first2=B. I. |last3=Aggarwal |first3=M. M. |last4=Ahammed |first4=Z. |last5=Alakhverdyants |first5=A. V. |last6=Alekseev |first6=I. |last7=Anderson |first7=B. D. |last8=Arkhipkin |first8=D. |last9=Averichev |first9=G. S. |last10=Balewski |first10=J. |last11=Barnby |first11=L. S. |last12=Baumgart |first12=S. |last13=Beavis |first13=D. R. |last14=Bellwied |first14=R. |last15=Betancourt |first15=M. J. |date=2010-04-02 |title=Observation of an Antimatter Hypernucleus |url=https://www.science.org/doi/10.1126/science.1183980 |journal=Science |language=en |volume=328 |issue=5974 |pages=58–62 |doi=10.1126/science.1183980 |pmid=20203011 |issn=0036-8075|arxiv=1003.2030 |bibcode=2010Sci...328...58. }}</ref> have also been previously observed.