Revisiting $D_{s0}^{*}(2317)$ as a $0^{+}$ tetraquark state from QCD sum rules (1801.08725v2)

Abstract: Stimulated by the renewed observation of $D_{s0}^{*}(2317)$ signal and its updated mass value $2318.3\pm1.2\pm1.2~\mbox{MeV}/c^{2}$ in the process $e^{+}e^{-}\rightarrow D_{s}^{+}D_{s0}^{}(2317)^{-}+c.c.$ by BESIII Collaboration, we devote to reinvestigate $D_{s0}^{*}(2317)$ as a $0^{+}$ tetraquark state from QCD sum rules. Technically, four different possible currents are adopted and high condensates up to dimension $12$ are included in the operator product expansion (OPE) to ensure the quality of QCD sum rule analysis. In the end, we obtain the mass value $2.37^{+0.50}_{-0.36}~\mbox{GeV}$ with the factorization parameter $\rho=1$ (or $2.23^{+0.78}_{-0.24}~\mbox{GeV}$ with $\rho=3$) for the scalar-scalar current, which agrees well with the experimental data of $D_{s0}^{*}(2317)$ and could support its explanation as a $0^{+}$ scalar-scalar tetraquark state. The final result for the axial-axial configuration is calculated to be $2.51^{+0.61}_{-0.43}~\mbox{GeV}$ with $\rho=1$ (or $2.52^{+0.76}_{-0.52}~\mbox{GeV}$ with $\rho=3$), which is still consistent with the mass of $D_{s0}^{*}(2317)$ considering the uncertainty, and then the possibility of $D_{s0}^{*}(2317)$ as a axial-axial tetraquark state can not be excluded. For the pseudoscalar-pseudoscalar and the vector-vector cases, their unsatisfactory OPE convergence makes that it is of difficulty to find rational work windows to further acquire hadronic masses.