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arXiv · 1908.06992

Neutrino mass ordering obscured by non-standard interactions

Abstract

One of the major open questions in particle physics is the issue of the neutrino mass ordering (NMO). The current data of the two long-baseline experiments NO$ν$A and T2K, interpreted in the standard 3-flavor scenario, provide a $\sim2.4σ$ indication in favor of the normal neutrino mass ordering. We show that such an indication is completely washed out if one assumes the existence of neutral-current non-standard interactions (NSI) of the flavor changing type involving the $e-τ$ flavors. This implies that the claim for a discovery of the NMO will require a careful consideration of the impact of hypothetical NSI.

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Francesco Capozzi, Sabya Sachi Chatterjee, Antonio Palazzo. 2020-02-19. Neutrino mass ordering obscured by non-standard interactions. https://doi.org/10.1103/physrevlett.124.111801

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