# Revisiting the vector leptoquark explanation of the B-physics anomalies

## TL;DR

This paper thoroughly investigates the vector leptoquark hypothesis as an explanation for B-physics anomalies, considering recent experimental results, model conditions, and implications for low-energy observables within a motivated theoretical framework.

## Contribution

It introduces a comprehensive analysis of vector leptoquarks including right-handed couplings and demonstrates how these can be realized in a UV-complete model, reinforcing their viability for explaining anomalies.

## Key findings

- Vector leptoquarks can successfully explain B-physics anomalies.
- Right-handed couplings and flavor mixing are crucial for model success.
- Compatibility with low-energy observables and UV completions is established.

## Abstract

We present a thorough investigation of the vector leptoquark hypothesis for a combined explanation of the $B$-physics anomalies. We analyze this hypothesis from a twofold perspective, taking into account recent results from $B$-physics observables and high-$p_T$ searches. First, using a simplified model, we determine the general conditions for a successful low-energy fit in presence of right-handed leptoquark couplings (neglected in previous analyses). Second, we show how these conditions, in particular a sizable 2-3 family mixing, can be achieved in a motivated ultraviolet completion. Our analysis reinforces the phenomenological success of the vector leptoquark hypothesis in addressing the anomalies, and its compatibility with motivated extensions of the Standard Model based on the idea of flavor non-universal gauge interactions. The implications of right-handed leptoquark couplings for a series of key low-energy observables, namely $B_s \to \tau\tau$ and $\tau\to\mu$ lepton flavor violating processes, both in $\tau$ and in $B$ decays, are discussed in detail. The role of the ultraviolet completion in precisely estimating other low-energy observables, most notably $\Delta F=2$ amplitudes, is also addressed.