# Probing $CPT$ breaking induced by quantum decoherence at DUNE

Carrasco, J. C. (Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú) ; Díaz, F. N. (Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú) ; Gago, A. M. (Sección Física, Departamento de Ciencias, Pontificia Universidad Católica del Perú, Apartado 1761, Lima, Perú)

16 April 2019

Abstract: We show that the decoherence phenomena applied to the neutrino system could lead to an observable breaking of the fundamental $CPT$ symmetry. We require specific textures of nondiagonal decoherence matrices, with nonzero ${\delta }_{CP}$, for making such observations. Using the information from the $CPT$ conjugate channels ${\nu }_{\mu }\to {\nu }_{\mu }$ and ${\overline{\nu }}_{\mu }\to {\overline{\nu }}_{\mu }$ and their corresponding backgrounds, we have estimated the sensitivity of the DUNE experiment for testing $CPT$ under the previous conditions. Four scenarios for energy-dependent decoherence parameters, ${\Gamma }_{{E}_{\nu }}=\Gamma ×\left({E}_{\nu }/\mathrm{GeV}{\right)}^{n}$, $n=-1$, 0, 1, and 2, are taken into account, and for most of them, DUNE is able to achieve a $5\sigma$ discovery potential, having $\Gamma$ in $O\left({10}^{-23}\text{}\text{}\mathrm{GeV}\right)$ for ${\delta }_{CP}=3\pi /2$. Meanwhile, for ${\delta }_{CP}=\pi /2$, we reach $3\sigma$ for $\Gamma$ in $O\left({10}^{-24}\text{}\text{}\mathrm{GeV}\right)$.

Published in: Physical Review D 99 (2019)