CP asymmetries from non-unitarity leptonic mixing

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.