Determining 1 -- heavy hybrid masses via QCD sum rules

The masses of 1?? charmonium and bottomonium hybrids are evaluated in terms of QCD sum rules. We find that the ground state hybrid in the charm sector lies in GeV, while in the bottom sector the hybrid may be situated in GeV. Since the numerical result on the charmonium hybrid mass is not compatible with the charmonium spectra, including structures newly observed in experiment, we attempt to conclude that such a hybrid does not purely exist, but rather as an admixture with other states, like glueball and regular quarkonium, in experimental observation. However, our result on the bottomonium hybrid coincides with the ?exotic structure? recently observed at BELLE.