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arXiv · 1605.04512

Helicity oscillations of Dirac and Majorana neutrinos

Alexandra Dobrynina·Alexander Kartavtsev·Georg Raffelt
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Abstract

The helicity of a Dirac neutrino with mass $m$ evolves under the influence of a $B$-field because it has a magnetic dipole moment proportional to $m$. Moreover, it was recently shown that a polarized or anisotropic medium engenders the same effect for both Dirac and Majorana neutrinos. Because a $B$-field polarizes a background medium, it instigates helicity oscillations even for Majorana neutrinos unless the medium is symmetric between matter and antimatter. Motivated by these observations, we review the impact of a $B$-field and of an anisotropic or polarized medium on helicity oscillations for Dirac and Majorana neutrinos from the common perspective of in-medium dispersion.

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Alexandra Dobrynina, Alexander Kartavtsev, Georg Raffelt. 2016-05-15. Helicity oscillations of Dirac and Majorana neutrinos. https://doi.org/10.1103/physrevd.93.125030

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