The masses of the 0^{++} and 0^{-+} light-quark hybrids using QCD sum rules

We calculate the masses of the light-quark hybrid mesons with the quantum numbers and by using the QCD sum rules. Two kinds of interpolated currents with the same quantum numbers are employed. We find that approximately equal masses are predicted for the hybrid state using the different currents, and different masses are obtained for the hybrid state using the different currents. The prediction depends on the interaction between the gluon and the quarks in the low-lying hybrid mesons. The mixing effect on the mass of the light-quark hybrid mesons through the low-energy theorem has also been examined, and it is found that this mixing shifts the masses of the hybrid mesons and the glueball a little. Received: 17 July 1998 / Revised version: 11 September 1998 / Published online: 15 April 1999