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arXiv · hep-ph/0308150

Heavy quarkonium hyperfine structure and leptonic decays

D. Ebert·R. N. Faustov·V. O. Galkin
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Abstract

The relation between the hyperfine structure and leptonic decay rates of heavy quarkonia is considered with the account of relativistic and radiative corrections. The calculated decay rates agree well with the available experimental data, while the predicted eta_c(2S) mass is significantly smaller than the value measured recently by the Belle and BaBar Collaborations.

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D. Ebert, R. N. Faustov, V. O. Galkin. 2003-08-14. Heavy quarkonium hyperfine structure and leptonic decays. https://arxiv.org/abs/hep-ph/0308150

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