Probing CPT breaking induced by quantum decoherence at DUNE

Abstract

We show that, the decoherence phenomena applied to the neutrino system could lead us to have an observable breaking of the fundamental CPT symmetry. We require a specific textures of non-diagonal decoherence matrices, with non-zero $\delta_{CP}$, for having such observations. Using the information from the CPT conjugate channels: $\nu_{\mu} \rightarrow \nu_{\mu}$ and $\bar{\nu}_{\mu} \rightarrow \bar{\nu}_{\mu}$ and its corresponding backgrounds, we have estimated the sensitivity of DUNE experiment for testing CPT under the previous conditions. Four scenarios for energy dependent decoherence parameters $\Gamma_{E_\nu}=\Gamma \times (E_\nu/\mathrm{GeV})^n$, $n=-1,0,1,$ and $2$ are taken into account, for most of them, DUNE is able to achieve a 5$\sigma$ discovery potential having $\Gamma$ in $\mathcal{O} (10^{-23}$ GeV) for $\delta_{CP}=3\pi/2$. Meanwhile, for $\delta_{CP}=\pi/2$ we reach 3$\sigma$ for $\Gamma$ in $\mathcal{O} (10^{-24}$ GeV).