Width of the exotic $X_b(5568)$ state through its strong decay to $B_s^{0} \pi^{+}$

TL;DR

This paper calculates the decay width of the exotic $X_b(5568)$ state using QCD sum rules, finding results consistent with experimental measurements, thus providing insight into its structure and decay properties.

Contribution

The study applies light-cone QCD sum rules with a soft-meson approximation to determine the decay width of $X_b(5568)$, offering a novel theoretical prediction aligned with experimental data.

Findings

Predicted decay width agrees with D0 Collaboration data

Computed strong coupling $g_{X_b B_s \pi}$ for the $X_b(5568)$ state

Validated the diquark-antidiquark current model for this exotic state

Abstract

The width of the newly observed exotic state $X_b(5568)$ is calculated via its dominant strong decay to $% B_s^{0} \pi^{+}$ using the QCD sum rule method on the light-cone in conjunction with the soft-meson approximation. To this end, the vertex $X_{b}B_{s}\pi$ is studied and the strong coupling $g_{X_{b}B_{s}\pi}$ is computed employing for $X_b(5568)$ state the interpolating diquark-antidiquark current of the $[su][\overline{b}\overline{d}]$ type. The obtained prediction for the decay width of $X_b(5568)$ is confronted and a nice agreement found with the experimental data of the D0 Collaboration.