  The $X17$ particle, discovered by Krasznahorkay et al. at ATOMKI, was
recently confirmed in the $\gamma \gamma$ invariant mass spectra by Abraamyan
et al. at JINR. We notice with surprise and interest that the $X17$ seems to
have a double-peak structure. This is in a possible coincidence with our QCD
sum rule study of [arXiv:2006.01018], where we interpreted the $X17$ as a
tetraquark state composed of four bare quarks ($u \bar u d \bar d$), and
claimed that ``A unique feature of this tetraquark assignment is that we
predict two almost degenerate states with significantly different widths''.
These two different tetraquark states are described by two different chiral
tetraquark currents $\bar u_L \gamma_\mu d_L~\bar d_L \gamma^\mu u_L$ and $\bar
u_L \gamma_\mu d_L~\bar d_R \gamma^\mu u_R$. To verify whether the tetraquark
assignment is correct or not, we replace the up and down quarks by the strange
quarks, and apply the QCD sum rule method to study the other four chiral
tetraquark currents $\bar u_L \gamma_\mu s_L~\bar s_L \gamma^\mu u_L$, $\bar
u_L \gamma_\mu s_L~\bar s_R \gamma^\mu u_R$, $\bar d_L \gamma_\mu s_L~\bar s_L
\gamma^\mu d_L$, and $\bar d_L \gamma_\mu s_L~\bar s_R \gamma^\mu d_R$. We
calculate their correlation functions, and find that non-perturbative QCD
effects do not contribute much to them. Our results suggest that there may
exist 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 $d \bar d s \bar s$.
