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Quantum Chromodynamics (QCD) sum rules are used to study the mass spectrum of bottom-charm hybrid systems. The correlation functions and the spectral densities are calculated up to dimension six condensates at leading order of αs for several JP quantum numbers. After performing the QCD sum rule analysis, we predict the masses of the JP = 0−, 0+, 1−, 1+, 2−, 2+ bottom-charm hybrids. These mass predictions show a similar supermultiplet structure as the bottomonium and charmonium hybrids. Using the QCD sum rule mass predictions we analyze the possible hadronic decay patterns of the , and hybrids including the open-flavor and hidden-flavor mechanisms. [ABSTRACT FROM AUTHOR]

Axial vector (JPC = 1++) charmonium and bottomonium hybrid masses are determined via QCD Laplace sum-rules. Previous sum-rule studies in this channel did not incorporate the dimension-six gluon condensate, which has been shown to be important for 1-- and 0-+ heavy quark hybrids. An updated analysis of axial vector charmonium and bottomonium hybrids is presented, including the effects of the dimension-six gluon condensate. The axial vector charmonium and bottomonium hybrid masses are predicted to be 5.13 and 11.32 GeV, respectively. We discuss the implications of this result for the charmonium-like 'XYZ' states and the charmonium hybrid multiplet structure observed in recent lattice calculations. [ABSTRACT FROM AUTHOR]

We reanalyze the 1−+ light hybrid from QCD sum rules with a Monte-Carlo based on uncertainty analysis. With 30% uncertainties in the accepted central values for QCD condensates and other input parameters, we obtain a prediction on the 1−+ hybrid mass of 1.71 ± 0.22 GeV, which covers the mass of π1(1600). We also study the correlations between the input and output parameters of QCD sum rules. [ABSTRACT FROM AUTHOR]