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arXiv · 0805.2916

Spectroscopy, leptonic decays and the nature of heavy quarkonia

Juan-Luis Domenech-Garret·Miguel-Angel Sanchis-Lozano
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Abstract

We examine the electronic width ratios of Upsilon resonances below the BBbar threshold by means of an effective (Cornell-type) QCD potential incorporating 1/m_b corrections obtained from a prior fit to the bottomonium spectrum. From our analysis we conclude that the Upsilon(2S) and Upsilon(3S) states should belong to the strong-coupling (nonperturbative) regime while the Upsilon(1S) state should belong to the weak-coupling (perturbative) regime, in agreement with a previous study based on radiative decays.

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Juan-Luis Domenech-Garret, Miguel-Angel Sanchis-Lozano. 2008-09-14. Spectroscopy, leptonic decays and the nature of heavy quarkonia. https://doi.org/10.1016/j.physletb.2008.09.021

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