Probing CP Violation in Neutrino-antineutrino Oscillations with Non-unitary Flavor Mixing

TL;DR

This paper investigates CP violation in neutrino-antineutrino oscillations considering non-unitary flavor mixing, revealing potential deviations from standard CP asymmetry predictions due to heavy-light neutrino mixing effects.

Contribution

It introduces the impact of non-unitary flavor mixing on CP violation in neutrino-antineutrino oscillations within the type-I seesaw framework, highlighting deviations from the unitarity limit.

Findings

CP asymmetries can significantly deviate from the unitarity limit.

Non-unitary mixing parameters influence CP violation effects.

Current experimental bounds constrain the extent of deviation.

Abstract

If massive neutrinos are Majorana particles, then the lepton number should be violated and neutrino-antineutrino oscillations will take place. In this talk, we present the properties of CP violation in neutrino-antineutrino oscillations with a non-unitary leptonic flavor mixing matrix, which naturally arises in the type-I seesaw model due to the mixing between light and heavy Majorana neutrinos. Taking into account current experimental bounds on the leptonic unitarity violation, we show that the CP asymmetries induced by the non-unitary mixing parameters can significantly deviate from those in the unitarity limit.