Update on non-unitary mixing in the recent NO$\nu$A and T2K data

Abstract

In this paper, we have tested the non-unitary mixing hypothesis with the latest data from NO$\nu$A and T2K experiments. We have also analysed their combined data. We have provided the best-fit values of the standard and non standard parameters after the analysis. $90\%$ limits on the non-unitary mixing parameters have also been provided. The constraints on unitary violation is stronger, compared to the constraints obtained from previous data from NO$\nu$A and T2K. The tension between NO$\nu$A and T2K at the $1\,\sigma$ for normal mass hierarchy can be reduced for non-unitary mixing due to $\alpha_{10}$, albeit for a value of $|\alpha_{10}|$ larger than the present global $90\%$ limit. Additionally a study of the future sensitivity of NO$\nu$A, T2K and DUNE has been provided.