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arXiv · 1808.05062

$ \mu-\tau $ Reflection Symmetry and Its Explicit Breaking for Leptogenesis in a Minimal Seesaw Model

Abstract

The minimal seesaw framework, embroiling the Dirac neutrino mass matrix $ M_D $ and the Majorana neutrino mass matrix $ M_R $, is quite successful to explain the current global-fit results of neutrino oscillation data. In this context, we consider most predictive forms of $ M_D $ and $ M_R $ with two simple parameters, respectively. Considering these matrices, we obtain the low energy neutrino mass matrix under type-I seesaw formalism which obeys $ \mu-\tau $ reflection symmetry and predicts $ \theta_{23} = \pi/4$ and $ \delta = \pm \pi/2 $. In the given set-up, we also evaluate the Baryon Asymmetry of the Universe (BAU) through successful leptogenesis and find that perturbation of $ \mathcal{O}(10^{-2}) $ leads to the observed BAU and breaks exactness of the symmetry. Moreover, we also perform various correlation studies among different parameters in the framework of broken symmetry.

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BibTeXRIS

Newton Nath. 2018-08-15. $ \mu-\tau $ Reflection Symmetry and Its Explicit Breaking for Leptogenesis in a Minimal Seesaw Model. https://doi.org/10.1142/s0217732319503292

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