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تسجيل مستخدم جديدPDFs, $alpha_s$, and quark masses from global fits
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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} onumber alpha_s(M_Z)&=&0.1147pm0.0008~({rm exp.)}, onumber m_c(m_c)&=&1.252pm 0.018~({rm exp.})~{rm GeV}, onumber m_b(m_b)&=&3.83pm0.12~({rm exp.})~{rm GeV}, onumber m_t(m_t)&=&160.9pm1.1~({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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