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arXiv · hep-ph/0307151

Pseudo-Dirac Neutrinos, a Challenge for Neutrino Telescopes

John F. Beacom·Nicole F. Bell·Dan Hooper·John G. Learned·Sandip Pakvasa·Thomas J. Weiler
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Abstract

Neutrinos may be pseudo-Dirac states, such that each generation is actually composed of two maximally-mixed Majorana neutrinos separated by a tiny mass difference. The usual active neutrino oscillation phenomenology would be unaltered if the pseudo-Dirac splittings are $δm^2 \alt 10^{-12}$ eV$^2$; in addition, neutrinoless double beta decay would be highly suppressed. However, it may be possible to distinguish pseudo-Dirac from Dirac neutrinos using high-energy astrophysical neutrinos. By measuring flavor ratios as a function of $L/E$, mass-squared differences down to $δm^2 \sim 10^{-18}$ eV$^2$ can be reached. We comment on the possibility of probing cosmological parameters with neutrinos.

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John F. Beacom, Nicole F. Bell, Dan Hooper, John G. Learned, Sandip Pakvasa, Thomas J. Weiler. 2004-01-05. Pseudo-Dirac Neutrinos, a Challenge for Neutrino Telescopes. https://doi.org/10.1103/physrevlett.92.011101

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