Measuring the Leptonic CP Phase in Neutrino Oscillations with Non-Unitary Mixing

Abstract

Non-unitary neutrino mixing implies an extra CP violating phase that can fake the leptonic Dirac CP phase ${\delta }_{CP}$ of the simplest three-neutrino mixing benchmark scheme. This would hinder the possibility of probing for CP violation in accelerator-type experiments. We take T2K and T2HK as examples to demonstrate the degeneracy between the "standard" (or "unitary") and "non-unitary" CP phases. We find, under the assumption of non-unitary mixing, that their CP sensitivities severely deteriorate. Fortunately, the TNT2K proposal of supplementing T2(H)K with a $\mu$DAR source for better measurement of ${\delta }_{CP}$ can partially break the CP degeneracy by probing both $\cos {\delta }_{CP}$ and $\sin {\delta }_{CP}$ dependences in the wide spectrum of the $\mu$DAR flux. We also show that the further addition of a near detector to the $\mu$DAR setup can eliminate the degeneracy completely.

26 pages, latex, 11 figures, matches with PRD

References in corpus (8)

• Neutrino oscillations refitted
• Unitarity of the Leptonic Mixing Matrix
• Measurements of neutrino oscillation in appearance and disappearance channels by the T2K experiment with 6.6E20 protons on target
• Z_2 Symmetry Prediction for the Leptonic Dirac CP Phase
• New ambiguity in probing CP violation in neutrino oscillations
• Neutrino Oscillation Physics Potential of the T2K Experiment
• Minimal Dynamical Inverse See Saw
• Classifying CP transformations according to their texture zeros: theory and implications

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