Little Flavor and U(2) Family Symmetry

TL;DR

This paper explores a Little Flavor-inspired effective field theory with U(2)^2 symmetry, proposing a new approach to quark and lepton mass generation at TeV scales, predicting new gauge bosons, and addressing flavor violation constraints.

Contribution

It introduces a novel flavor symmetry framework with TeV-scale new physics, differing from traditional models by using U(2)^2 symmetry and explaining flavor phenomena.

Findings

Predicts new Z' and W' bosons at TeV scale

Suppresses flavor-changing neutral currents effectively

Lepton flavor violation processes near experimental bounds

Abstract

We examine an effective field theory inspired by Little Flavor that demonstrates a new paradigm for generating quark and lepton masses in which the scale of new flavor physics can be at the few TeV level, and new $Z'$ and $W'$ bosons are predicted. The model possesses an approximate $U(2)^2$ vector symmetry, not the full approximate $U(2)^5$ chiral symmetry of the Standard Model or Minimal Flavor Violation models, yet flavor changing neutral currents are sufficiently suppressed. Additionally, lepton flavor violating processes, such as $\mu\to 3e$, lie naturally just below experimental bounds and the down quark mass can be radiatively generated.