Systematic studies of charmonium-, bottomonium-, and -like tetraquark states
Jing Wu (School of Science, Shandong Jianzhu University, Jinan 250101, China); Xiang Liu (School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China and Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China); Yan-Rui Liu (School of Physics, Shandong University, Jinan 250100, China); Shi-Lin Zhu (School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China and Collaborative Innovation Center of Quantum Matter, Beijing 100871, China and Center of High Energy Physics, Peking University, Beijing 100871, China)
We study the mass splittings of (, , , , ) tetraquark states with chromomagnetic interactions between their quark components. Assuming that is the lowest tetraquark, we estimate the masses of the other tetraquark states. From the obtained masses and defined measure reflecting effective quark interactions, we find the following assignments for several exotic states: (1) both and the newly observed seem to be tetraquarks; (2) is probably a tetraquark; (3) , , and are unlikely compact tetraquarks; (4) is unlikely a compact tetraquark, but seems the hidden-charm correspondence of with ; and (5) can be a tetraquark candidate but the quantum numbers cannot be assigned at present. We hope further studies may check the predictions and assignments given here.
