Doubly heavy tetraquark states in a mass splitting model

Shi-Yuan Li, Yan-Rui Liu, Zi-Long Man +2

Treating the $X(4140)$ as a compact $J^{PC}=1^{++}$ $cs\bar{c}\bar{s}$ state and using its mass as a reference scale, we systematically estimate the masses of doubly heavy tetraqua…