Can nonstandard interactions jeopardize the hierarchy sensitivity of DUNE ?

Understand

We study the effect of non-standard interactions (NSIs) on the propagation of neutrinos through the Earth matter and how it affects the hierarchy sensitivity of the DUNE experiment.

• We emphasize on the special case when the diagonal NSI parameter $\epsilon_{ee} = -1$, nullifying the standard matter effect.
• We show that, if in addition, CP violation is maximal then this gives rise to an exact intrinsic hierarchy degeneracy in the appearance channel, irrespective of the baseline and energy.
• Introduction of off-diagonal NSI parameter, $\epsilon_{e \tau}$, shifts the position of this degeneracy to a different $\epsilon_{ee}$.