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arXiv · 1705.03450

Determination of the strong coupling at NNLO from jet production in DIS

Abstract

A first determination of the strong coupling $\alpha_s(m_Z)$ in next-to-next-to-leading order (NNLO) from inclusive jet and dijet production cross sections in deep-inelastic scattering at HERA is presented. Data collected by the H1 experiment in the years 1995 to 2007 covering the range of momentum transfer $5.5 4.5\,{\rm GeV}$ are explored. The strong coupling is determined in a fit to inclusive jet and dijet data to $\alpha_s(m_Z)=0.1157\,(6)_{\rm exp}\,(^{+31}_{-26})_{\rm theo}$. Further studies on the phenomenological application of the new NNLO calculations and on fits to the individual data sets are presented. The running of the strong coupling is probed in a single experiment over one order of magnitude in the remormalisation scale and consistency with the QCD expectations is found.

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Daniel Britzger. 2017-05-09. Determination of the strong coupling at NNLO from jet production in DIS. https://arxiv.org/abs/1705.03450

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