Computation of the quarkonium and meson-meson composition of the ϒ ( n S ) states and of the new ϒ ( 10753 <mml:mo …
2021; American Physical Society; Volume: 103; Issue: 7 Linguagem: Inglês
10.1103/physrevd.103.074507
ISSN2470-0037
AutoresPedro Bicudo, Nuno Cardoso, Lasse Müller, Marc Wagner,
Tópico(s)Physics of Superconductivity and Magnetism
ResumoWe compute the composition of the bottomonium $\mathrm{\ensuremath{\Upsilon}}(nS)$ states [including $\mathrm{\ensuremath{\Upsilon}}(10860)$] and the new $\mathrm{\ensuremath{\Upsilon}}(10753)$ resonance reported by Belle in terms of quarkonium and meson-meson components. We use a recently developed novel approach utilizing lattice QCD string breaking potentials for the study of resonances. This approach is based on the diabatic extension of the Born-Oppenheimer approximation and the unitary emergent wave method and allows us to compute the poles of the $\mathrm{S}$ matrix. We focus on $I=0$ bottomonium $S$ wave bound states and resonances, where the Schr\"odinger equation is a set of coupled differential equations. One of the channels corresponds to a confined heavy quark-antiquark pair $\overline{b}b$, and the others correspond to pairs of heavy-light mesons. In a previous study, only one meson-meson channel ${\overline{B}}^{(*)}{B}^{(*)}$ was considered. Now, we also include the closed strangeness channel ${\overline{B}}_{s}^{(*)}{B}_{s}^{(*)}$, extending our formalism significantly to have a more realistic description of bottomonium. We confirm the new Belle resonance $\mathrm{\ensuremath{\Upsilon}}(10753)$ as a dynamical meson-meson resonance with around 76% meson-meson content. Moreover, we identify $\mathrm{\ensuremath{\Upsilon}}(4S)$ and $\mathrm{\ensuremath{\Upsilon}}(10860)$ as states with both sizable quarkonium and meson-meson contents. With these results, we contribute to the clarification of ongoing controversies in the vector bottomonium spectrum.
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