New physics in $\text{b} \rightarrow \text{s}$ transitions in the MF331 model

TL;DR

This paper investigates how the MF331 model's new particles and interactions can explain B-meson decay anomalies, showing that box diagrams are essential and constraining new particle masses to match experimental data.

Contribution

It demonstrates that box diagrams are necessary to explain R_K and R_{K^*} anomalies in the MF331 model, and explores the resulting constraints on new particle masses.

Findings

Box diagrams are essential for explaining anomalies.

New particle masses are constrained by experimental data.

Predicted branching ratios align with experimental limits.

Abstract

There are two sources that help to explain the $\text{R}_\text{K}$, $\text{R}_{\text{K}^*}$ anomalies in the MF331 model. The first is non-LFUV couplings of the new neutral gauge boson $\text{Z}^{\prime}$ with leptons, $\text{g}^{\text{Z}^\prime}(e)\neq \text{g}^{\text{Z}^\prime}(\mu,\tau)$, which causes the $\text{R}_\text{K}$, $\text{R}_{\text{K}^*}$ anomalies via $\text{Z}^\prime$-penguin diagrams involving newly charged gauge bosons $\text{X}^{\pm}_{\mu}$, and exotic U-quarks. The box diagram's contribution is the second source, which induced only the first lepton generation. We show that the penguin diagrams can not explain $\text{R}_\text{K}$, $\text{R}_{\text{K}^*}$ anomalies, and that the box diagram is required. The experimental constraints for $\text{R}_\text{K}$ and $\text{R}_{\text{K}^*}$ result in new particle mass degeneracy. The contributions of NP to the branching ratios $\text{Br}(\text{B}\to \mu^+ \mu^-), \text{Br}(\text{b}\to s \gamma)$ predict results that agree with the experimental limits in the allowed region of the NP scale.