Loop level bounds on seesaw neutrino mixing

Jacobo López Pavón

INFN, Genoa

 

We will analize the relevance of the 1-loop corrections when extracting bounds on non-unitarity in the context of low scale seesaws with an approximate B?L symmetry. These models are characterized by electroweak scale Majorana masses and large Yukawas. Previous results in the literature showed that a partial cancellation between these important loop corrections and the tree level contributions could relax some constraints. However, we will show that this cancellation can only take place in presence of large violations of the B?L symmetry, that lead to unacceptably large contributions to the light neutrino masses at loop level. The impact of the 1-loop corrections in the neutrinoless double beta decay phenomenology will also be discussed.