Gauged L_mu - L_tau Symmetry at the Electroweak Scale

TL;DR

This paper explores a gauged L_mu - L_tau symmetry extension of the Standard Model, addressing muon magnetic moment discrepancies, neutrino interactions, and potential collider signatures through detailed theoretical and experimental analysis.

Contribution

It introduces a new gauge symmetry extension that explains muon g-2, neutrino mixing, and predicts observable collider and lepton flavor violation signatures.

Findings

Allowed Z' mass range identified through electroweak data

Model explains muon g-2 discrepancy

Predicts lepton flavor violation and collider signatures

Abstract

The extension of the Standard Model by a spontaneously broken abelian gauge group based on the L(mu)-L(tau) lepton number can resolve the longstanding discrepancy between experimental and theoretical values for the magnetic moment of the muon. It furthermore naturally generates mu-tau symmetric lepton mixing, introduces neutrino non-standard interactions, and the associated gauge boson Z' serves as a mediator to the right-handed neutrino sector. A detailed fit to electroweak data is performed to identify the allowed values for the mass of Z' and its mixing with the Standard Model Z. An economical new scalar sector is constructed that spontaneously breaks the new symmetry and leads to experimental consequences such as lepton flavor violation and collider signatures. Furthermore we discuss the non-abelian extension to an SU(2)', particularly the neutrino sector.