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arXiv · 2401.17131

Estimating the strong coupling from $\tau$ decay using accelerating series convergence

K. Schilcher·C. Sebu·H. Spiesberger
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Abstract

We apply the Euler transformation to accelerate the convergence of the QCD perturbative series with the aim to determine the strong coupling $\alpha_s$ in terms of the total $\tau$-decay rate $r_\tau$. The variation of the result with the order of the QCD perturbation theory is small and comparable with the uncertainties of $r_\tau$. We also present an estimate of a range of the yet unknown 5th and 6th order coefficients $k_5$ and $k_6$ of the Adler function.

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K. Schilcher, C. Sebu, H. Spiesberger. 2024-01-30. Estimating the strong coupling from $\tau$ decay using accelerating series convergence. https://arxiv.org/abs/2401.17131

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