Sensitivity of T2KK to the non-standard interaction in propagation

TL;DR

This paper investigates T2KK's ability to detect non-standard neutrino interactions during propagation, focusing on specific parameters and their potential to be constrained or measured, thus advancing understanding of neutrino physics beyond the Standard Model.

Contribution

It introduces a study of T2KK's sensitivity to certain non-standard neutrino interaction parameters under specific assumptions, highlighting potential constraints and phase measurements.

Findings

T2KK can constrain |_{ee}|  1 and |_{e}|  0.2.

If |_{e}| and _{13} are large, T2KK can separately determine the Dirac phase and the phase of _{e}.

Components |_{}| for =e,, must be small for consistency with atmospheric neutrino data.

Abstract

Assuming only the non-zero electron and tau neutrino components $\epsilon_{ee}$, $\epsilon_{e\tau}$, $\epsilon_{\tau\tau}$ of the non-standard matter effect and postulating the atmospheric neutrino constraint $\epsilon_{\tau\tau}=|\epsilon_{e\tau}|^2/(1+\epsilon_{ee})$, we study the sensitivity to the non-standard interaction in neutrino propagation of the T2KK neutrino long-baseline experiment. It is shown that T2KK can constrain the parameters $|\epsilon_{ee}|\lesssim 1$, $|\epsilon_{e\tau}|\lesssim 0.2$. It is also shown that if $|\epsilon_{e\tau}|$ and $\theta_{13}$ are large, then T2KK can determine the Dirac phase and the phase of $\epsilon_{e\tau}$ separately, due to the information at the two baselines. We also provide an argument that the components $|\epsilon_{\alpha\mu}|$ $(\alpha=e,\mu,\tau)$ must be small for the disappearance oscillation probability to be consistent with high-energy atmospheric neutrino data, which justifies our premise that these quantities are negligible.