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arXiv · 1609.07417

PDFs, $\alpha_s$, and quark masses from global fits

S. Alekhin·J. Bluemlein·S. Moch·R. Placakyte
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Abstract

The strong coupling constant $\alpha_s$ and the heavy-quark masses, $m_c$, $m_b$, $m_t$ are extracted simultaneosly with the parton distribution functions (PDFs) in the updated ABM12 fit including recent data from CERN-SPS, HERA, Tevatron, and the LHC. The values of \begin{eqnarray} \nonumber \alpha_s(M_Z)&=&0.1147\pm0.0008~({\rm exp.)},\\ \nonumber m_c(m_c)&=&1.252\pm 0.018~({\rm exp.})~{\rm GeV},\\ \nonumber m_b(m_b)&=&3.83\pm0.12~({\rm exp.})~{\rm GeV},\\ \nonumber m_t(m_t)&=&160.9\pm1.1~({\rm exp.})~{\rm GeV} \end{eqnarray} are obtained with the $\overline{MS}$ heavy-quark mass definition being employed throughout the analysis.

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S. Alekhin, J. Bluemlein, S. Moch, R. Placakyte. 2016-09-23. PDFs, $\alpha_s$, and quark masses from global fits. https://arxiv.org/abs/1609.07417

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