The isospin asymmetry in $B \to K^* \mu^+ \mu^-$ using AdS/QCD

TL;DR

This paper calculates the isospin asymmetry in the rare decay $B o K^* \mu^+\mu^-$ using AdS/QCD and Sum Rules, predicting a sign change in asymmetry at low $q^2$ and comparing results with LHCb data.

Contribution

It introduces a novel calculation of isospin asymmetry in $B$ decay using AdS/QCD, providing predictions that are less model-dependent at higher $q^2$.

Findings

Positive asymmetry at $q^2=0$ that flips sign around 1-2 GeV$^2$

Asymmetry remains small (≤2%) at higher $q^2$

Predictions align with recent LHCb measurements

Abstract

We compute the isospin asymmetry distribution in the rare dileptonic decay $B \to K^* \mu^+ \mu^-$, in the dimuon mass squared ($q^2$) region below the $J/\Psi$ resonance, using non-perturbative inputs as predicted by the anti-de Sitter/Quantum Chromodynamics (AdS/QCD) correspondence and by Sum Rules. We predict a positive asymmetry at $q^2=0$ which flips sign in the region $q^2 \in [1,2]~\mbox{GeV}^2$ to remain small ($\le 2\%$) and negative for larger $q^2$. While our predictions are distinct as $q^2 \to 0$, they become hardly model-dependent $q^2 \ge 4~\mbox{GeV}^2$. We compare our predictions to the most recent LHCb data.