Interpretation of Lepton Flavor Violation

TL;DR

This paper discusses how observing charged-lepton flavor violation can indicate physics beyond the Standard Model, analyzing the implications of such processes and their relation to lepton number violation in a model-independent way.

Contribution

It provides a classification scheme for lepton-flavor-violating processes based on quantum numbers and explores how their detection can reveal the breaking of the entire flavor symmetry group.

Findings

Lepton-flavor-violating processes indicate specific symmetry violations.

Certain processes are necessary to confirm complete flavor symmetry breaking.

Lepton number violation implies lepton flavor violation.

Abstract

The observation of a charged-lepton flavor violating process would be a definite sign for physics beyond the Standard Model, but would actually only prove that one particular linear combination of lepton numbers is violated. We categorize lepton-flavor-violating processes by their quantum numbers and show how their discovery can be interpreted model independently, studying in particular which processes are required to establish that the entire flavor group is broken. We also comment on total lepton number, seeing as lepton number violation practically implies lepton flavor violation as well.