Predicting $B -> \rho \gamma$ and $B_s -> \rho \gamma$ using holographic AdS/QCD Distribution Amplitudes for the $\rho$ meson

TL;DR

This paper develops holographic AdS/QCD Distribution Amplitudes for the transversely polarized ta meson and uses them to predict branching ratios for specific B meson radiative decays, achieving agreement with experimental data and overcoming divergence issues.

Contribution

It introduces holographic AdS/QCD Distribution Amplitudes for the ta meson and applies them to B decay predictions, improving upon sum rule approaches.

Findings

Predicted ta decay branching ratios agree with experimental data.

AdS/QCD DAs avoid end-point divergences present in sum rule DAs.

Predictions are consistent with existing theoretical and experimental results.

Abstract

We derive holographic AdS/QCD Distribution Amplitudes for the transversely polarised $\rho$ meson and we use them to predict the branching ratio for the decays $\bar B^\circ\rightarrow \rho^\circ \gamma$ and $\bar B^\circ_s\rightarrow \rho^\circ \gamma$ beyond leading power accuracy in the heavy quark limit. For $\bar B^\circ\rightarrow \rho^\circ \gamma$, our predictions agree with those generated using Sum Rules (SR) Distribution Amplitudes and with the data from the BaBar and Belle collaborations. In computing the weak annihilation amplitude which is power-supressed in $\bar B^\circ\rightarrow \rho^\circ \gamma$ but is the leading contribution in $\bar{B}^{\circ}_s\rightarrow \rho^\circ \gamma$, we find that, in its present form, the AdS/QCD DA avoids the end-point divergences encountered with the SR DA .