Open-Channel Effects on Heavy-Quarkonium Spectra: A Phenomenological Study Within a One-Open-Channel Approximation

摘要

Open-channel effects on charmonium (S- and D-waves) and bottomonium (S-wave) J~P = 1~- spectra are investigated within a one-open-channel approximation. Mass shifts and decay widths of these states just above the threshold are obtained by taking into account a coupling between confined quarkonium states and decaying states of the open channel. The final-state interaction (FSI) between the decaying meson and antimeson plays a very important role in producing a reasonable magnitude of coupling; the FSI provides the open-channel poles (R_1, R_2) at the appropriate positions on the complex energy plane. The result is found to be independent of the detailed form of the transition potential and the final-state interaction.