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arXiv · 1505.02624

$\alpha_s$ determination at NNLO$^\star$+NNLL accuracy from the energy evolution of jet fragmentation functions at low $z$

David d'Enterria·and Redamy Pérez-Ramos
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Abstract

The QCD coupling $\alpha_s$ is extracted from the energy evolution of the first two moments (multiplicity and mean) of the parton-to-hadron fragmentation functions at low fractional hadron momentum $z$. Comparisons of the experimental $e^+e^-$ and deep-inelastic $e^\pm$p jet data to our NNLO$^*$+NNLL predictions, allow us to obtain $\alpha_s(m_{_{\rm Z}})$ = 0.1205$\pm$0.0010$^{+0.0022}_{-0.0000}$, in excellent agreement with the current world average determined using other methods at the same level of accuracy.

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David d'Enterria, and Redamy Pérez-Ramos. 2015-05-11. $\alpha_s$ determination at NNLO$^\star$+NNLL accuracy from the energy evolution of jet fragmentation functions at low $z$. https://arxiv.org/abs/1505.02624

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