Exploring the spectrum of heavy quarkonium hybrids with QCD sum rules

QCD Laplace sum rules are used to calculate heavy quarkonium (charmonium and bottomonium) hybrid masses in several distinct J(PC) channels. Previous studies of heavy quarkonium hybrids did not include the effects of dimension-six condensates, leading to unstable sum rules and unreliable mass predictions in some channels. We have updated these sum rules to include dimension-six condensates, providing new mass predictions for the spectra of heavy quarkonium hybrids. We confirm the finding of other approaches that the negative-parity J(PC) = (0, 1, 2)(-+), 1(--) states form the lightest hybrid supermultiplet and the positive-parity J(PC) = (0, 1)+-, (0, 1, 2)(++) states are members of a heavier supermultiplet. Our results disfavor a pure charmonium hybrid interpretation of the X(3872), in agreement with previous work.