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arXiv · 1010.0583

Dirac neutrino magnetic moment and a possible time evolution of the neutrino signal from a supernova

R. A. Anikin·A. V. Kuznetsov·N. V. Mikheev
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Abstract

We analyze the influence of neutrino helicity conversion, $ν_L \to ν_R$, on the neutrino flux from a supernova caused by the interaction of the Dirac neutrino magnetic moment with a magnetic field. We show that if the neutrino has a magnetic moment in the interval $10^{-13} \, μ_{\rm B} < μ_ν< 10^{-12} \, μ_{\rm B}$ and provided that a magnetic field of $\sim 10^{13} - 10^{14}$ G exists in the supernova envelope, a peculiar kind of time evolution of the neutrino signal from the supernova caused by the resonance transition $ν_L \to ν_R$ in the magnetic field of the envelope can appear. If a magnetar with a poloidal magnetic field is formed in a supernova explosion, then the neutrino signal could have a pulsating behavior, i.e., a kind of a neutrino pulsar could be observed, when it rotates around an axis that does not coincide with its magnetic moment and when the orientation of its rotation axis is favourable for our observation.

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R. A. Anikin, A. V. Kuznetsov, N. V. Mikheev. 2010-10-04. Dirac neutrino magnetic moment and a possible time evolution of the neutrino signal from a supernova. https://doi.org/10.1134/s1063773710090069

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