# Discovery potential of T2K and NO*v*A in the presence of a light sterile neutrino

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## Abstract

We study the impact of one light sterile neutrino on the prospective data expected to come from the two presently running long-baseline experiments T2K and NO*v*A when they will accumulate their full planned exposure. Introducing for the first time, the bi-probability representation in the 4-flavor framework, commonly used in the 3-flavor scenario, we present a detailed discussion of the behavior of the *v* _{ μ } → *v* _{ e } and \( {\overline{v}}_{\mu}\to {\overline{v}}_e \) transition probabilities in the 3+1 scheme. We also perform a detailed sensitivity study of these two experiments (both in the stand-alone and combined modes) to assess their discovery reach in the presence of a light sterile neutrino. For realistic benchmark values of the mass-mixing parameters (as inferred from the existing global short-baseline fits), we find that the performance of both these experiments in claiming the discovery of the CP-violation induced by the standard CP-phase \( \delta \) _{13} = \( \delta \) and the neutrino mass hierarchy get substantially deteriorated. The exact loss of sensitivity depends on the value of the unknown CP-phase \( \delta \) _{14}. Finally, we estimate the discovery potential of total CP-violation (i.e., induced simultaneously by the two CP-phases \( \delta \) _{13} and \( \delta \) _{14}), and the capability of the two experiments of reconstructing the true values of such CP-phases. The typical (1\( \sigma \) level) uncertainties on the reconstructed phases are approximately 40^{0} for \( \delta \) _{13} and 50^{0} for \( \delta \) _{14}.

## Keywords

Neutrino Physics Beyond Standard Model## Notes

**Open Access**

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