# Lepton flavor universality violation without new sources of quark flavor violation

## TL;DR

This paper proposes a new physics framework explaining recent anomalies in $b\to s\ell^+\ell^-$ transitions without introducing new quark flavor violation, predicting a light $Z'$ boson detectable at the LHC.

## Contribution

It introduces a model where lepton flavor universality violation occurs without new quark flavor violating interactions, via a $Z'$ penguin mechanism.

## Key findings

- The $Z'$ boson can explain the $b\to s\ell^+\ell^-$ anomalies.
- The scenario predicts a light $Z'$ detectable at the LHC.
- The model naturally produces a $V-A$ structure in quark currents.

## Abstract

We show that new physics models without new flavor violating interactions can explain the recent anomalies in the $b\to s\ell^+\ell^-$ transitions. The $b\to s\ell^+\ell^-$ arises from a $Z'$ penguin which automatically predicts the $V-A$ structure for the quark currents in the effective operators. This framework can be realized either in a renormalizable $U(1)'$ setup or be due to new strongly interacting dynamics. The di-muon resonance searches at the LHC are becoming sensitive to this scenario since the $Z'$ is relatively light, and could well be discovered in future searches by ATLAS and CMS.