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arXiv · 1010.1206

Lower Bounds on U_{e3}

Shamayita Ray·Werner Rodejohann·Michael A. Schmidt
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Abstract

We give minimal values for the smallest lepton mixing parameter U_{e3}, applying 2-loop renormalization group equations in an effective theory approach. This is relevant in scenarios that predict an inverted neutrino mass spectrum with the smallest mass and U_{e3} being zero at tree level, a situation known to be preserved at 1-loop order. At 2-loop, U_{e3} is generated at a level of 10^{-12}-10^{-14}. Such small values are of interest in supernova physics. Corresponding limits for the normal mass ordering are several orders of magnitude larger. Our results show that U_{e3} can in general expected be to be non-zero.

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Shamayita Ray, Werner Rodejohann, Michael A. Schmidt. 2010-10-06. Lower Bounds on U_{e3}. https://doi.org/10.1103/physrevd.83.033002

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