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The strong running coupling from the gauge sector of Domain Wall lattice QCD with physical quark masses

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 نشر من قبل Savvas Zafeiropoulos
 تاريخ النشر 2019
  مجال البحث
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We report on the first computation of the strong running coupling at the physical point (physical pion mass) from the ghost-gluon vertex, computed from lattice simulations with three flavors of Domain Wall fermions. We find $alpha_{overline{rm MS}}(m_Z^2)=0.1172(11)$, in remarkably good agreement with the world-wide average. Our computational bridge to this value is the Taylor-scheme strong coupling, which has been revealed of great interest by itself because it can be directly related to the quark-gluon interaction kernel in continuum approaches to the QCD bound-state problem.



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