Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada.
School of Physics and Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beihang University, Beijing 100191, China.
Phys Rev Lett. 2016 Jul 8;117(2):022002. doi: 10.1103/PhysRevLett.117.022002. Epub 2016 Jul 6.
We investigate the recent evidence for a charged X(5568) meson as an exotic open-flavor tetraquark state sub[over ¯]d[over ¯] with J^{P}=0^{+}/1^{+} in the framework of QCD sum rules. We use the color antisymmetric [3[over ¯]{c}]{su}⊗[3_{c}]{b[over ¯]d[over ¯]} tetraquark currents in both scalar and axial-vector channels to perform evaluations and numerical analyses. Our results imply that the X(5568) can be interpreted as both the scalar sub[over ¯]d[over ¯] tetraquark state and the axial-vector one, which are in good agreement with the experimental measurement. We also discuss the possible decay patterns of the X(5568) and suggest to search for its neutral partner in the radiative decay into B{s}^{0}γ and B_{s}^{*}γ, which can be used to determine its spin-parity quantum numbers. Moreover, we predict its charmed partner state around 2.55 GeV with the quark content suc[over ¯]d[over ¯] and J^{P}=0^{+}/1^{+}.
我们在 QCD 求和规则框架内研究了作为奇异开放味四夸克态 sub[over ¯]d[over ¯]的带电荷 X(5568)介子的最新证据，其宇称为 J^{P}=0^{+}/1^{+}。我们使用标量和轴向矢量通道中的颜色反称 [3[over ¯]{c}]{su}⊗[3_{c}]{b[over ¯]d[over ¯]} 四夸克流进行评估和数值分析。我们的结果表明，X(5568)可以被解释为标量 sub[over ¯]d[over ¯]四夸克态和轴向矢量态，这与实验测量结果一致。我们还讨论了 X(5568)的可能衰变模式，并建议在辐射衰变为 B{s}^{0}γ 和 B_{s}^{*}γ 中寻找其中性伴子，这可以用来确定其自旋-宇称量子数。此外，我们预测其在 2.55 GeV 左右的伴子态，其夸克内容为 suc[over ¯]d[over ¯]，宇称为 J^{P}=0^{+}/1^{+}。
