The $0^{++}$ and $0^{-+}$ mass of light-quark hybrid in QCD sum rules
  We calculate masses of the light-quark hybrid mesons with the quantum number $0^{++}$ and $0^{-+}$ by using the QCD sum rules. Two kinds of the interpolated currents with the same quantum number are employed. We find that the approximately equal mass is predicted for the $0^{-+}$ hybrid state from the different current and the different mass is obtained for the $0^{++}$ hybrid state from the different current. The prediction depends on the interaction between the gluon and quarks in the low-lying hybrid mesons. The mixing effect on the mass of the light-quark hybrid meson through Low-energy theorem has been examined too, and it is found that this mixing shifts the mass of hybrid meson and glueball a little. 
Tao Huang, Hongying Jin, Ailin Zhang