Analysis of the Possible and Molecules with QCD Sum Rules**Supported by National Natural Science Foundation of China under Grant No. 11775079

Abstract

In this article, we assume that there exist the pseudoscalar and molecular states Z1,2 and construct the color singlet-singlet molecule-type interpolating currents to study their masses with the QCD sum rules. In calculations, we consider the contributions of the vacuum condensates up to dimension-10 and use the formula to determine the energy scales of the QCD spectral densities. The numerical results, and , which lie above the and thresholds respectively, indicate that the and are difficult to form bound state molecular states, the Z1,2 are probably resonance states.