# Flavor Non-universality Gauge Interactions and Anomalies in B-Meson Decays

## TL;DR

This paper systematically constructs anomaly-free $U(1)'$ gauge theories addressing flavor non-universality and anomalies in B-meson decays, proposing models that induce flavor-changing interactions and are testable via collider and meson mixing experiments.

## Contribution

It provides a general framework for building anomaly-free non-universal $U(1)'$ models with specific charge assignments and explores their implications for B-meson decay anomalies.

## Key findings

- Derived a condition for anomaly cancellation with non-universal charges.
- Identified five independent solutions for charge assignments.
- Discussed experimental probes like meson mixing and collider searches.

## Abstract

Motivated by flavor non-universality and anomalies in semi-leptonic B-meson decays, we present a general and systematic discussion about how to construct anomaly-free $U(1)'$ gauge theories based on an extended standard model with only three right-handed neutrinos. If all standard model fermions are vector-like under this new gauge symmetry, the most general family non-universal charge assignments, $(a,b,c)$ for three-generation quarks and $(d,e,f)$ for leptons, need satisfy just one condition to be anomaly-free, $3(a+b+c)=-(d+e+f)$. Any assignment can be linear combinations of five independent anomaly-free solutions. We also illustrate how such models can generally lead to flavor-changing interactions and easily resolve the anomalies in B-meson decays. Probes with $B_s-\bar{B}_s$ mixing, decay into $\tau^\pm$, dilepton and dijet searches at colliders are also discussed.