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arXiv · 1408.2865

Extraction of alpha_s from the energy evolution of jet fragmentation functions at low z

David d'Enterria·and Redamy Perez-Ramos
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Abstract

A novel method to extract the QCD coupling alpha_s from the energy evolution of the moments of the parton-to-hadron fragmentation functions at low fractional hadron momentum z, is presented. The evolution of the moments (multiplicity, peak, width, skewness) of the charged-hadron distribution in jets is computed at NMLLA+NLO* accuracy and compared to the experimental deep-inelastic e-p data. Values of the strong coupling constant at the Z pole are obtained, alpha_s(m_Z) = 0.119 +/- 0.010, in excellent numerical 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 Perez-Ramos. 2014-08-12. Extraction of alpha_s from the energy evolution of jet fragmentation functions at low z. https://arxiv.org/abs/1408.2865

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