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arXiv · hep-ph/9508333

Flavor-Changing Magnetic Dipole Moment and Oscillation of a Neutrino in a Degenerate Electron Plasma

Abstract

The standard model prediction for a magnetic dipole moment of a neutrino is proportional to the neutrino mass and extremely small. It also generates a flavor-changing process, but the GIM mechanism reduces the corresponding amplitude. These properties of a neutrino magnetic moment change drastically in a degenerate electron plasma. We have shown that an electron-hole excitation gives a contribution proportional to the electrons' Fermi momentum. Since this effect is absent in \(μ\) and \(τ\) sector, the GIM cancellation does not work. The magnetic moment induces a neutrino oscillation if a strong enough magnetic field exists in the plasma. The required magnitude of the field strength that affects the \nue\ burst from a supernova is estimated to be the order of \(10^8 \) Gauss.

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Hisashi Kikuchi. 1995-08-23. Flavor-Changing Magnetic Dipole Moment and Oscillation of a Neutrino in a Degenerate Electron Plasma. https://arxiv.org/abs/hep-ph/9508333

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