Deciphering the charged heavy quarkoniumlike states in chiral effective field theory

摘要

We generalize the framework of chiral effective field theory to study the interactions of the isovector D * D ˉ ( * ) and B * B ˉ ( * ) systems up to the next-to-leading order, in which the long-, mid-, and short-range force contributions as well as the S ? D wave mixing are incorporated. Based on the Lippmann-Schwinger equation, we fit the invariant mass distributions of the elastic channels measured by the BESIII and Belle Collaborations. Our results indicate that the four charged charmoniumlike and bottomoniumlike states Z c ( 3900 ) , Z c ( 4020 ) and Z b ( 10610 ) , Z b ( 10650 ) can be well identified as the D D ˉ * , D * D ˉ * and B B ˉ * , B * B ˉ * molecular resonances. The bound state explanations are vetoed in our framework. Our study favors the Z c and Z b states are the twin partners under the heavy quark symmetry.