2014/11/10 by Timothy J. Burns, T. J. Burns, Burns, T. J.
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #Quantum chaos and dynamical systems #hep-ph
paper · pdf · doi:10.48550/arxiv.1411.2485
Presented at the Workshop on Unquenched Hadron Spectroscopy: Non-Perturbative Models and Methods of QCD vs. Experiment (EEF70)
arxiv created 2014/11/10 · openalex publication_date 2014/11/10 · arxiv updated 2014/11/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
General results are obtained for meson mass splittings and mixings in unquenched (coupled-channel) quark models. Theorems derived previously in perturbation theory are generalised to the full coupled-channel system. A new formula is obtained for the mass splittings of physical states in terms of the splittings of the valence states. The S-wave hyperfine splitting decreases due to unquenching, but its relation to the vector e+e- width is unchanged; this yields a prediction for the missing ηb(3S). The ordinary (quenched) quark model result that the P-wave hyperfine splitting vanishes also survives unquenching. A ratio of mass splittings used to discriminate quarkonium potential models is scarcely affected by unquenching.