Light tetraquark state candidates

Abstract

In this article, we study the axialvector-diquark-axialvector-antidiquark type scalar, axialvector, tensor and vector $ss\bar{s}\bar{s}$ tetraquark states with the QCD sum rules. The predicted mass $m_X=2.08\pm 0.12\mathrm{GeV}$ for the axialvector tetraquark state is in excellent agreement with the experimental value $(2062.8\pm 13.1\pm 4.2)\mathrm{MeV}$ from the BESIII collaboration and supports assigning the new $X$ state to be a $ss\bar{s}\bar{s}$ tetraquark state with $J^{PC}=1^{+-}$. The predicted mass $m_X=3.08\pm 0.11\mathrm{GeV}$ disfavors assigning the $\varphi (2170)$ or $Y(2175)$ to be the vector partner of the new $X$ state. As a byproduct, we obtain the masses of the corresponding $qq\bar{q}\bar{q}$ tetraquark states. The light tetraquark states lie in the region about $2\mathrm{GeV}$ rather than $1\mathrm{GeV}$.

Comments: 9 pages, 6 figures