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The $X17$ particle, discovered by Krasznahorkay et al. at ATOMKI, wasrecently confirmed in the $\gamma \gamma$ invariant mass spectra by Abraamyanet al. at JINR. We notice with surprise and interest that the $X17$ seems tohave a double-peak structure. This is in a possible coincidence with our QCDsum rule study of [arXiv:2006.01018], where we interpreted the $X17$ as atetraquark state composed of four bare quarks ($u \bar u d \bar d$), andclaimed that ``A unique feature of this tetraquark assignment is that wepredict two almost degenerate states with significantly different widths''.These two different tetraquark states are described by two different chiraltetraquark currents $\bar u_L \gamma_\mu d_L~\bar d_L \gamma^\mu u_L$ and $\baru_L \gamma_\mu d_L~\bar d_R \gamma^\mu u_R$. To verify whether the tetraquarkassignment is correct or not, we replace the up and down quarks by the strangequarks, and apply the QCD sum rule method to study the other four chiraltetraquark currents $\bar u_L \gamma_\mu s_L~\bar s_L \gamma^\mu u_L$, $\baru_L \gamma_\mu s_L~\bar s_R \gamma^\mu u_R$, $\bar d_L \gamma_\mu s_L~\bar s_L\gamma^\mu d_L$, and $\bar d_L \gamma_\mu s_L~\bar s_R \gamma^\mu d_R$. Wecalculate their correlation functions, and find that non-perturbative QCDeffects do not contribute much to them. Our results suggest that there mayexist four almost degenerate tetraquark states with masses about $236\sim296$MeV. Each of these states is composed of four bare quarks, either $u \bar u s\bar s$ or $d \bar d s \bar s$.

QCD sum rule studies on the possible double-peak structure of the $X17$ particle