CP asymmetries from non-unitarity leptonic mixing

TL;DR

This paper explores how non-unitary leptonic mixing matrices, arising from new physics theories, can produce significant CP asymmetries in neutrino oscillations, serving as a probe for beyond Standard Model physics.

Contribution

It demonstrates that extra CP-phases in non-unitary matrices can lead to observable CP asymmetries in neutrino oscillations, highlighting a new method to detect new physics.

Findings

Non-unitary mixing matrices can generate sizeable CP asymmetries.

CP asymmetries in $ u_ o u_ au$ are sensitive probes of new physics.

Extra CP-phases are crucial for observable effects.

Abstract

A low-energy non-unitary leptonic mixing matrix is a generic effect of some theories of new physics accounting for neutrino masses. We show how the extra CP-phases of a general non-unitary matrix allow for sizeable CP-asymmetries in the $\nu_\mu\to \nu_\tau$ channel. This CP-asymmetries turns out to be an excellent probe of such new physics.