Quantum effects on neutrino parameters from a flavored gauge boson

TL;DR

This paper studies how a family-dependent gauge boson affects neutrino mass evolution, showing it can increase the mass matrix rank at one-loop and potentially generate observed neutrino properties.

Contribution

It demonstrates that an extended gauge sector can induce one-loop rank increase in the neutrino mass matrix, unlike Standard Model fields which do so only at two loops.

Findings

Extra gauge boson increases neutrino mass matrix rank at one-loop.

Quantum effects can generate observed neutrino mass differences and mixing angles.

Contrasts with Standard Model where rank increases only at two-loop level.

Abstract

We calculate the one-loop renormalization group equations of the neutrino mass matrix when the Standard Model particle content is extended with a massive gauge boson which has family-dependent couplings to the left-handed leptons. We show that quantum effects induced by the extra gauge boson increase the rank of the neutrino mass matrix at the one-loop level, in contrast to the well-known result that Standard Model fields can only increase the rank at the two-loop level. We also discuss the possibility of generating dynamically the measured mass differences and mixing angles between the active neutrinos in scenarios with normal and inverted mass ordering.