B Decays in an Asymmetric Left-Right Model

TL;DR

This paper investigates $B$ meson decays within an asymmetric left-right model, analyzing how new right-handed interactions could explain observed deviations from the Standard Model predictions.

Contribution

It introduces a simplified right-handed quark mixing matrix in an asymmetric left-right model and constrains its parameters using experimental data, highlighting potential observable differences from the Standard Model.

Findings

Identifies parameter regions with significant right-handed contributions to $B$ decays.

Shows large parameter space where left- and right-handed quark mixings differ.

Suggests possible experimental signatures distinguishing the model from the Standard Model.

Abstract

Motivated by recently observed disagreements with the SM predictions in $B$ decays, we study $b \to d, s$ transitions in an asymmetric class of $SU(2)_L \times SU(2)_R \times U(1)_{B-L}$ models, with a simple one-parameter structure of the right handed mixing matrix for the quarks, which obeys the constraints from kaon physics. We use experimental constraints on the branching ratios of $b \to s \gamma$, $b \to c e {\bar \nu}_e$, and $B_{d,s}^0 -\bar{B}^0_{d,s}$ mixing to restrict the parameters of the model: $\displaystyle {g_R}/{g_L}, M_{W_2}, M_{H^\pm}, \tan \beta$ as well as the elements of the right-handed quark mixing matrix $V^R_{CKM}$. We present a comparison with the more commonly used (manifest) left-right symmetric model. Our analysis exposes the parameters most sensitive to $b$ transitions and reveals a large parameter space where left- and right-handed quarks mix differently, opening the possibility of observing marked differences in behaviour between the standard model and the left-right model.