QCD Sum Rule study of $J^P = 1^\pm$ exotic states with two heavy quarks in the molecular picture

In this study, the spectroscopic parameters of the exotic molecular states composed of mesons containing two heavy quarks (scalar-axial and pseudoscalar-axial meson combinations) are investigated within QCD sum rules. Our findings reveal that the molecular states containing charm quarks do not form bound states, whereas the states with b-quarks can form the exotic molecular states. This observation has significant implications for understanding the structure of these exotic states.
Comment: To be published in Chinese Physics C