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New results on heavy quarks near threshold

M. Beneke
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Abstract

We review in brief the threshold expansion, a method to perform the expansion of Feynman integrals near the heavy quark-antiquark threshold, and its relation to the construction of two effective theories, non-relativistic QCD (NRQCD) and potential-NRQCD. We then summarize recent next-to-next-to-leading order results on the decay $J/Ψ\to l^+ l^-$, the bottom quark mass from $Υ$ sum rules and the top-anti-top production cross section near threshold in $e^+ e^-$ collisions.

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M. Beneke. 1998-06-25. New results on heavy quarks near threshold. https://arxiv.org/abs/hep-ph/9806429

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