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Nature of the vector resonance $Y\left(2175\right)$

2020    Agaev, S. S.; Azizi, K.; Sundu, H.

Spectroscopic parameters and decay channels of the vector resonance $Y\left(2175\right)$ are studied by considering it as a diquark-antidiquark state with the quark content $su\overline{s}\overline{u}$. The mass and coupling of the tetraquark $Y\left(2175\right)$ are calculated using the QCD two-point sum rules by taking into account various quark, gluon and mixed condensates up to dimension 15. Partial widths of its strong decays to $\varphi {f}_{0}\left(980\right)$, $\varphi \eta $, and $\varphi {\eta }^{\prime }$ are computed as well. To this end, we explore the vertices $Y\varphi {f}_{0}\left(980\right)$, $Y\varphi \eta $, and $Y\varphi {\eta }^{\prime }$, and calculate the corresponding strong couplings by means of the QCD light-cone sum rule method. The coupling ${G}_{Y\varphi f}$ of the vertex $Y\varphi {f}_{0}\left(980\right)$ is found using the full version of this method, and by treating the scalar meson ${f}_{0}\left(980\right)$ as a diquark-antidiquark tetraquark state. The couplings ${g}_{Y\varphi \eta }$ and ${g}_{Y\varphi {\eta }^{\prime }}$, however, are calculated by applying the soft-meson approximation to the light-cone sum rule method. Prediction for the mass of the resonance ${m}_{Y}=\left(2173±85\right)\text{}\text{}\mathrm{MeV}$ is in excellent agreement with the data of the BABAR Collaboration [Phys. Rev. D 74, 091103 (2006)], and within errors of calculations is compatible with the result reported by BESIII [Phys. Rev. D 91, 052017 (2015)]. The full width ${\Gamma }_{\mathrm{full}}=\left(91.1±20.5\right)\text{}\text{}\mathrm{MeV}$ of the $Y\left(2175\right)$ saturated by its three strong decay channels is in a reasonable agreement with existing experimental data.