Speaker
Description
The mixing of three active neutrino flavors is parameterized by the unitary PMNS matrix. If there are more than three neutrino flavors and if the extra generations are heavy isosinglets, the effective 3 × 3 mixing matrix for the three active neutrinos will be non-unitary. We have analyzed the latest T2K and NOνA data with the hypothesis of non-unitary mixing of the active neutrinos. We found that the NOνA data slightly prefer the non-unitary mixing over unitary mixing. Allowing the non-unitary mixing brings the NOνA best-fit point closer to the T2K best-fit point. The T2K data, on the other hand, prefer unitary mixing. A combined analysis of the NOνA and T2K data also prefers the unitary mixing but cannot rule out the 1σ C.L. non-unitary region derived from the NOνA data alone.
Mini-abstract
NO$\nu$A data prefer non-unitary mixing. T2K data prefer unitary mixing. Bestfit points are closer.