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arXiv · 1604.05690

New ambiguity in probing CP violation in neutrino oscillations

O. G. Miranda·M. Tortola·J. W. F. Valle
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Abstract

If neutrinos get mass via the seesaw mechanism the mixing matrix describing neutrino oscillations can be effectively non-unitary. We show that in this case the neutrino appearance probabilities involve a new CP phase, phi, associated to non-unitarity. This leads to an ambiguity in extracting the "standard" three--neutrino phase delta_CP, which can survive even after neutrino and antineutrino channels are combined. Its existence should be taken into account in the planning of any oscillation experiment aiming at a robust measurement of delta_CP.

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O. G. Miranda, M. Tortola, J. W. F. Valle. 2016-08-11. New ambiguity in probing CP violation in neutrino oscillations. https://doi.org/10.1103/physrevlett.117.061804

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