A QCD sum rule calculation of the $X^\pm(5568) \to B_{s}^0\pi^\pm$ decay width

TL;DR

This paper uses QCD sum rules to calculate the decay width of the $X(5568)$ particle, supporting its interpretation as a scalar tetraquark based on the agreement with experimental data.

Contribution

It extends previous mass calculations by applying three-point QCD sum rules to determine the decay width of $X(5568)$, providing evidence for its tetraquark structure.

Findings

Decay width calculated as (20.4±8.7) MeV

Result agrees with experimental value of 21.9±6.4 MeV

Supports the scalar tetraquark interpretation of $X(5568)$

Abstract

To understand the nature of the $X(5568)$, recently observed in the mass spectrum of the $B_{s}^0\pi^\pm$ system by the D0 Collaboration, we have investigated, in a previous work, a scalar tetraquark (diquak-antidiquark) structure for it, within the two-point QCD sum rules method. The result found for its mass agrees well with the experimental value. Encouraged by this finding we now extend our calculations to obtain the decay width of $X(5568)$ to $B_{s}^0\pi^\pm$ using the three-point QCD sum rule. We obtain a value of $(20.4\pm8.7)\MeV$, which, on comparing with the experimental value of $21.9\pm6.4 (\mbox{sta})^{+5.0}_{-2.5}(\mbox{syst}) \MeV/c^2$, reinforces the scalar four quark nature of $X(5568)$.