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Inclusive electromagnetic decays of the heavy quarkonium at next to leading log accuracy

Antonio Pineda
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Abstract

We show that perturbation theory may give reasonable numbers for the decays of the bottomonium and charmonium ground states to $e^+e^-$ and to $γγ$. To reach this conclusion it is important to perform the resummation of logs. In particular, we obtain the value $Γ(η_b (1S) \to γγ)=0.35 \pm 0.1 ({\rm th.}) \pm 0.05 (\lQ)$ KeV.

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Antonio Pineda. 2004-04-26. Inclusive electromagnetic decays of the heavy quarkonium at next to leading log accuracy. https://arxiv.org/abs/hep-ph/0404225

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