Uncovering the Majorana nature through a precision measurement of the CP phase

We show the possibility to discover the neutrino nature by measuring the Majorana CP phase at the DUNE experiment. This phase is turned on by a decoherence environment, possibly originated by physics at the Planck scale. A sizable distortion in the measurement of the Dirac CP violation phase δCP is observed at DUNE when compared with T2HK measurement due to decoherence and the non-null Majorana phase. Being that, when the measurement of the Majorana phase is performed at DUNE, it reaches a precision of 23(21)% for a decoherence parameter Γ=4.5(5.5)×10-24 GeV and a Majorana phase equal to 1.5π. The latter precision is similar to the one obtained at the T2K experiment at its current Dirac CP violation phase measurement.