Interpretation of $Ω(2012)$ as a $Ξ(1530)K$ molecular state
Xiang Yu, Jin-Peng Zhang, Xu-Liang Chen, Ding-Kun Lian, Qi-Nan Wang, Wei Chen
Abstract
We investigate the mass and strong decay properties of the $Ω(2012)$ resonance using QCD sum rules, assuming it to be an S-wave $Ξ(1530)K$ molecular pentaquark state with $IJ^{P} = 0\frac{3}{2}^{-}$. A unified interpolating current is constructed, and the two-point and three-point correlation functions are calculated up to dimension-10 condensates in the OPE series. The negative-parity contribution is isolated by employing parity-projected sum rules. The two-body strong decays to $Ξ^0 K^-$ and $Ξ^- K^0$ are studied via their three-point correlation functions. Our analysis yields a mass of $2.00 \pm 0.15~\mathrm{GeV}$ and a total two-body decay width of $Γ= 3.97^{+8.31}_{-1.92}~\mathrm{MeV}$ for the $Ξ(1530)K$ molecular state. The ratios of branching fractions are obtained as $\mathcal{R}^{Ξ^- K^0}_{Ξ^0 K^-} = 0.85$ and $\mathcal{R}^{ΞπK}_{ΞK} = 0.61$. These results are compatible well with the experimental data for the $Ω(2012)$ and support its interpretation as a $Ξ(1530)K$ molecular pentaquark state.
