Constraining the isotropic CPT-odd coefficients of the Standard Model Extension by a combined DUNE and ESSnuSB analysis

TL;DR

This paper combines data from DUNE and ESSnuSB to set new constraints on isotropic CPT-odd coefficients in the Standard Model Extension, improving limits and exploring parameter correlations.

Contribution

It provides the first combined analysis of DUNE and ESSnuSB data to constrain isotropic CPT-odd SME coefficients, enhancing existing limits and examining parameter correlations.

Findings

Strongest limit on $(a_L)_{6}2^T$ from combined data

Correlation analysis between SME coefficients and oscillation parameters

Discussion of SME coefficient $(a_L)^Z$ effects on neutrino propagation

Abstract

Based on an analysis that considers the isotropic CPT-odd Standard Model Extension (SME) coefficients, we find new constraints for them coming from a combined DUNE and ESSnuSB fit. Furthermore, we investigate the correlations of the standard oscillation parameters, the leptonic CP-violating phase, $\delta_{CP}$, and the atmospheric mixing angle, $\sin^2 \theta_{23}$, with respect to the SME coefficients $(a_L)^T$. The combination of DUNE and ESSnuSB may establish the strongest limit on the diagonal coefficient $(a_L)_{\mu \mu}^T$ compared to the existing limits in the literature. We also consider the possible effect of the SME coefficient $(a_L)^Z$ on neutrino propagation and discuss how this can affect DUNE limits on the coefficient $(a_L)^T$ found elsewhere.