Heavy Quarkonium (1−−) Meson-Hybrid Mixing from QCD Sum Rules

Abstract

We use QCD Laplace sum-rules to explore mixing between conventional mesons and hybrids in the heavy quarkonium vector JPC=1−− channel. Our cross-correlator includes perturbation theory and contributions proportional to the four-dimensional and six-dimensional gluon condensates. We input experimentally determined charmonium and bottomonium hadron masses into both single and multi-resonance models in order to test them for conventional meson and hybrid components. In the charmonium sector we find evidence for meson-hybrid mixing in the J/ψ and a ≈ 4.3 GeV resonance. In the bottomonium sector, we find that the ϒ(1S), ϒ(2S), ϒ(3S), and ϒ(4S) all exhibit mixing.