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 J PC = 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.