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arXiv · 2105.09332

Charm-quark mass effects in NRQCD matching coefficients and the leptonic decay of the $\Upsilon(1S)$ meson

Manuel Egner·Matteo Fael·Jan Piclum·Kay Schoenwald·Matthias Steinhauser
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Abstract

We compute two-loop corrections to the vector current matching coefficient involving two heavy quark masses. The result is applied to the computation of the $\Upsilon(1S)$ decay width into an electron or muon pair. We complement the next-to-next-to-next-to-leading order corrections of Ref. arXiv:1401.3005 by charm quark mass effects up to second order in perturbation theory. Furthermore, we apply the formalism to $\Gamma(J/\Psi\to \ell^+\ell^-)$ and compare to the experimental data.

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Manuel Egner, Matteo Fael, Jan Piclum, Kay Schoenwald, Matthias Steinhauser. 2021-05-19. Charm-quark mass effects in NRQCD matching coefficients and the leptonic decay of the $\Upsilon(1S)$ meson. https://doi.org/10.1103/physrevd.104.054033

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