Editing Neutron (section)

=== Antineutron ===
{{Main|Antineutron}}

The antineutron is the [[antiparticle]] of the neutron. It was discovered by [[Bruce Cork]] in 1956, a year after the [[antiproton]] was discovered. Neutrons have [[baryon number]] equal to 1 while antineutrons have -1. While all measured particle interactions conserve baryon number, [[baryon asymmetry|matter dominates over antimatter in the cosmos]] suggesting that there must be some way to change the baryon number. One proposed mechanism is [[Neutral particle oscillation|neutron-antineutron oscillations]] which might be detectable.<ref>{{Cite journal |last=Phillips |first=D. G. |last2=Snow |first2=W. M. |last3=Babu |first3=K. |last4=Banerjee |first4=S. |last5=Baxter |first5=D. V. |last6=Berezhiani |first6=Z. |last7=Bergevin |first7=M. |last8=Bhattacharya |first8=S. |last9=Brooijmans |first9=G. |last10=Castellanos |first10=L. |last11=Chen |first11=M. -C. |last12=Coppola |first12=C. E. |last13=Cowsik |first13=R. |last14=Crabtree |first14=J. A. |last15=Das |first15=P. |date=2016-02-11 |title=Neutron-antineutron oscillations: Theoretical status and experimental prospects |url=https://linkinghub.elsevier.com/retrieve/pii/S0370157315004457 |journal=Physics Reports |volume=612 |pages=1–45 |doi=10.1016/j.physrep.2015.11.001 |issn=0370-1573}}</ref><ref>{{cite journal | last=A. Addazi | display-authors=et al.| title=New high-sensitivity searches for neutrons converting into antineutrons and/or sterile neutrons at the HIBEAM/NNBAR experiment at the European Spallation Source | journal=Journal of Physics G | volume=48 | year=2021 | doi=10.1088/1361-6471/abf429 | pages=070501}}</ref> The lower limit on the period of oscillations 0.86x10<sup>8</sup> s (90% CL) was obtained using cold neutrons.<ref>{{cite journal | last=M. Baldo-Ceolin | display-authors=et al.| title=A new experimental limit on neutron-antineutron oscillations | journal=Z. Phys. C | volume=63 | year=1994 | doi=10.1007/BF01580321 | pages=409-416}}</ref> [[Ultracold neutrons]] may increase the sensitivity by 10–40 times, depending on the model of neutron reflection from walls.<ref>{{cite journal | last=A.K. Fomin | display-authors=et al.| title=Experiment on search for neutron–antineutron oscillations using a projected UCN source at the WWR-M reactor | journal=Journal of Physics: Conference Series | volume=798 | year=2017 | doi=10.1088/1742-6596/798/1/012115 | pages=012115}}</ref>