Neutral particle oscillation

In particle physics, neutral particle oscillation is the transmutation of a particle with zero electric charge into another neutral particle due to a change of a non-zero internal quantum number, via an interaction that does not conserve that quantum number. Neutral particle oscillations were first investigated in 1954 by Murray Gell-mann and Abraham Pais.^[1]

For example, a neutron cannot transmute into an antineutron as that would violate the conservation of baryon number. But in those hypothetical extensions of the Standard Model which include interactions that do not strictly conserve baryon number, neutron–antineutron oscillations are predicted to occur.^[2]^[3]^[4] There is a project to search for neutron–antineutron oscillations using ultracold neutrons.^[5]^[6]^[7]^[8]

Such oscillations can be classified into two types:

Particle–antiparticle oscillation (for example, $K 0 ⇄ K 0$ oscillation, $B 0 ⇄ B 0$ oscillation, $D 0 ⇄ D 0$ oscillation^[9]).
Flavor oscillation (for example, $ν e ⇄ ν μ ⇄ ν τ$ oscillation).

In those cases where the particles decay to some final product, then the system is not purely oscillatory, and an interference between oscillation and decay is observed.

^ Gell-mann, M.; Pais, A. (1 March 1955). "Behavior of Neutral Particles under Charge Conjugation". Physical Review. 97 (5): 1385. Bibcode:1955PhRv...97.1387G. doi:10.1103/PhysRev.97.1387.
^ Mohapatra, R.N. (2009). "Neutron-anti-neutron oscillation: Theory and phenomenology". Journal of Physics G. 36 (10): 104006. arXiv:0902.0834. Bibcode:2009JPhG...36j4006M. doi:10.1088/0954-3899/36/10/104006. S2CID 15126201.
^ Giunti, C.; Laveder, M. (19 August 2010). "Neutron oscillations". Neutrino Unbound. Istituto Nazionale di Fisica Nucleare. Archived from the original on 27 September 2011. Retrieved 19 August 2010.
^ Kamyshkov, Y.A. (16 January 2002). Neutron → antineutron oscillations (PDF). Large Detectors for Proton Decay, Supernovae, and Atmospheric Neutrinos and Low Energy Neutrinos from High Intensity Beams. NNN 2002 Workshop. CERN, Switzerland. Retrieved 19 August 2010.
^ Serebrov, A.; Fomin, A.; Kamyshkov, Y. (2016). "Sensitivity of Experiment on Search for Neutron–Antineutron Oscillations on the Projected Ultracold Neutron Source at the WWR-M Reactor". Technical Physics Letters. 42 (1): 99–101. Bibcode:2016TePhL..42...99S. doi:10.1134/S1063785016010314.
^ A.K. Fomin; et al. (2017). "Experiment on search for neutron–antineutron oscillations using a projected UCN source at the WWR-M reactor". Journal of Physics: Conference Series. 798 (1): 012115. Bibcode:2017JPhCS.798a2115F. doi:10.1088/1742-6596/798/1/012115.
^ A.K. Fomin (2017). "Experiment On Search For n-nbar Oscillations Using A Projected UCN Source At The WWR-M Reactor". Proceedings of Science. 281: 189. doi:10.22323/1.281.0189.
^ A.K. Fomin; et al. (2019). "Project on searching for neutron-antineutron oscillation at the WWR-M reactor". Journal of Physics: Conference Series. 1390 (1): 012133. Bibcode:2019JPhCS1390a2133F. doi:10.1088/1742-6596/1390/1/012133.
^ Griffiths, D.J. (2008). Elementary Particles (2nd, Revised ed.). Wiley-VCH. p. 149. ISBN 978-3-527-40601-2.

[1] Gell-mann, M.; Pais, A. (1 March 1955). "Behavior of Neutral Particles under Charge Conjugation". Physical Review. 97 (5): 1385. Bibcode:1955PhRv...97.1387G. doi:10.1103/PhysRev.97.1387.

[2] Mohapatra, R.N. (2009). "Neutron-anti-neutron oscillation: Theory and phenomenology". Journal of Physics G. 36 (10): 104006. arXiv:0902.0834. Bibcode:2009JPhG...36j4006M. doi:10.1088/0954-3899/36/10/104006. S2CID 15126201.

[3] Giunti, C.; Laveder, M. (19 August 2010). "Neutron oscillations". Neutrino Unbound. Istituto Nazionale di Fisica Nucleare. Archived from the original on 27 September 2011. Retrieved 19 August 2010.

[4] Kamyshkov, Y.A. (16 January 2002). Neutron → antineutron oscillations (PDF). Large Detectors for Proton Decay, Supernovae, and Atmospheric Neutrinos and Low Energy Neutrinos from High Intensity Beams. NNN 2002 Workshop. CERN, Switzerland. Retrieved 19 August 2010.

[5] Serebrov, A.; Fomin, A.; Kamyshkov, Y. (2016). "Sensitivity of Experiment on Search for Neutron–Antineutron Oscillations on the Projected Ultracold Neutron Source at the WWR-M Reactor". Technical Physics Letters. 42 (1): 99–101. Bibcode:2016TePhL..42...99S. doi:10.1134/S1063785016010314.

[6] A.K. Fomin; et al. (2017). "Experiment on search for neutron–antineutron oscillations using a projected UCN source at the WWR-M reactor". Journal of Physics: Conference Series. 798 (1): 012115. Bibcode:2017JPhCS.798a2115F. doi:10.1088/1742-6596/798/1/012115.

[7] A.K. Fomin (2017). "Experiment On Search For n-nbar Oscillations Using A Projected UCN Source At The WWR-M Reactor". Proceedings of Science. 281: 189. doi:10.22323/1.281.0189.

[8] A.K. Fomin; et al. (2019). "Project on searching for neutron-antineutron oscillation at the WWR-M reactor". Journal of Physics: Conference Series. 1390 (1): 012133. Bibcode:2019JPhCS1390a2133F. doi:10.1088/1742-6596/1390/1/012133.

[9] Griffiths, D.J. (2008). Elementary Particles (2nd, Revised ed.). Wiley-VCH. p. 149. ISBN 978-3-527-40601-2.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]