Light axial-vector and vector resonances X(2100) and X(2239)

We study features of the resonances X(2100) and X(2239) by treating them as the axial-vector and vector tetraquarks with the quark content sss‾s‾, respectively. The spectroscopic parameters of these exotic mesons are calculated in the framework of the QCD two-point sum rule method. Obtained prediction for the mass m=(2067±84)MeV of the axial-vector state is in excellent agreement with the mass of the structure X(2100) recently observed by the BESIII Collaboration in the decay J/ψ→ϕηη′ as the resonance in the ϕη′ mass spectrum. We also explore the decays X(2100)→ϕη′ and X(2100)→ϕη using QCD light-cone sum rule approach and technical methods of the soft-meson approximation. The width of the axial-vector tetraquark, Γ=(130.2±30.1)MeV, saturated by these two processes is comparable with the measured full width of the resonance X(2100). Our prediction for the vector sss‾s‾ tetraquark's mass m˜=(2283±114)MeV is consistent with the experimental result (2239.2±7.1±11.3)MeV of the BESIII Collaboration for the mass of the resonance X(2239).