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Quarkonium Spectroscopy and Perturbative QCD: A New Perspective

N. Brambilla·Y. Sumino·A. Vairo
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Abstract

We study the energy spectrum of bottomonium in perturbative QCD, taking alpha_s(Mz)=0.1181 +/- 0.0020 as input and fixing m_b^{MSbar}(m_b^{MSbar}) on the Upsilon(1S) mass. Contrary to wide beliefs, perturbative QCD reproduces reasonably well the gross structure of the spectrum as long as the coupling constant remains smaller than one. We perform a detailed analysis and discuss the size of non-perturbative effects. A new qualitative picture on the structure of the bottomonium spectrum is provided. The lowest-lying (c,cbar) and (b,cbar) states are also examined.

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N. Brambilla, Y. Sumino, A. Vairo. 2001-05-07. Quarkonium Spectroscopy and Perturbative QCD: A New Perspective. https://doi.org/10.1016/s0370-2693(01)00611-6

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