Phenomenological consequences of residual ℤs2 and ℤ⎯⎯⎯s2 symmetries

The phenomenological consequences of the residual ℤs2 and ℤ⎯⎯⎯s2 symmetries are explored in detail. With a precisely measured value of the reactor angle, these two residual symmetries predict distinct distributions for the Dirac CP phase and the atmospheric angle, which lead to the possibility of identifying them at future neutrino experiments. For both symmetries, it is possible to resolve the neutrino mass hierarchy in most of the parameter space, and they can be distinguished from one another if the true residual symmetry is ℤs2 and the atmospheric angle is non-maximal. These results are obtained using an equally split schedule: a 1.5-year run of neutrinos and a 1.5-year run of antineutrinos at NOνA together with a 2.5-year run of neutrinos and a 2.5-year run of antineutrinos at T2K. This schedule can significantly increase and stabilize the sensitivities to the mass hierarchy and the octant of the atmospheric angle with only a moderate compromise to the sensitivity of distinguishing ℤs2 and ℤ⎯⎯⎯s2