Revisiting D s 0 ? ( 2317 ) as a 0 + tetraquark state from QCD sum rules

摘要

Stimulated by the renewed observation ofDs0?(2317)signal and its updated mass value2318.3±1.2±1.2MeV/c2in the processe+e?→Ds?+Ds0?(2317)?+c.c.by BESIII Collaboration, we devote to reinvestigateDs0?(2317)as a0+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 value2.37?0.36+0.50GeVwith the factorization parameterρ=1(or2.23?0.24+0.78GeVwithρ=3) for the scalar–scalar current, which agrees well with the experimental data ofDs0?(2317)and could support its explanation as a0+scalar–scalar tetraquark state. The final result for the axial–axial configuration is calculated to be2.51?0.43+0.61GeVwithρ=1(or2.52+0.76?0.52GeVwithρ=3), which is still consistent with the mass ofDs0?(2317)considering the uncertainty, and then the possibility ofDs0?(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.