https://doi.org/10.1051/epjconf/202225804001
Heavy-quark mesons in the diabatic approach: string breaking and the quarkoniumlike spectrum
Unidad Teórica, Instituto de Física Corpuscular (Universidad de Valencia–CSIC), E-46980 Paterna (Valencia), Spain
* e-mail: roberto.bruschini@ific.uv.es
Published online: 11 January 2022
The Born-Oppenheimer approximation provides a description of heavy-quark mesons firmly based on lattice QCD, but its validity is limited to the lightest states lying far below the first open-flavour meson-meson threshold. This limitation can be overcome in the diabatic framework, a formalism first introduced in molecular physics, where the dynamics is encoded in a potential matrix whose elements can be derived from unquenched lattice QCD studies of string breaking. The off-diagonal elements of the potential matrix provide interaction between heavy quark-antiquark and meson-meson pairs, from which the mixing of quarkonium states with molecular components and the OZI-allowed strong decay widths are directly calculated. This allows for a QCD-based unified description of conventional quarkonium and unconventional mesons containing quark-antiquark and meson-meson components, what has proved to be successful for charmoniumlike and bottomoniumlike resonances.
© The Authors, published by EDP Sciences, 2022
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