https://doi.org/10.1140/epjc/s10052-020-7938-2
Regular Article - Theoretical Physics
Fully open-flavor tetraquark states 
and 
with 
School of Physics, Sun Yat-Sen University, Guangzhou, 510275, China
* e-mail: chenwei29@mail.sysu.edu.cn
Received:
17
February
2020
Accepted:
15
April
2020
Published online:
8
May
2020
We have studied the masses for fully open-flavor tetraquark states and (
) with quantum numbers . We systematically construct all diquark–antiquark interpolating currents and calculate the two-point correlation functions and spectral densities in the framework of QCD sum rule method. Our calculations show that the masses are about 
GeV for the tetraquark states and 
GeV for the tetraquarks. The masses of tetraquarks are below the thresholds of 
and 
final states for the scalar and axial-vector channels respectively. The tetraquark states with 
lie below the 
and 
thresholds. Such low masses for these possible tetraquark states indicate that they can only decay via weak interaction and thus are very narrow and stable.
© The Author(s), 2020
