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arXiv · 1901.06424

Strong coupling constant and heavy quark masses in 2+1 flavor QCD

P. Petreczky·J. H. Weber
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Abstract

We present a determination of the strong coupling constant and heavy quark masses in (2+1)-flavor QCD using lattice calculations of the moments of the pseudo-scalar quarkonium correlators at several values of the heavy valence quark mass with Highly Improved Staggered Quark (HISQ) action. We determine the strong coupling constant in the $\overline{MS}$ scheme at four low-energy scales corresponding to $m_c$, $1.5m_c$, $2m_c$, and $3m_c$, with $m_c$ being the charm quark mass. The novel feature of our analysis that up to eleven lattice spacings are used in the continuum extrapolations, with the smallest lattice spacing being $0.025$ fm. We obtain $Λ_{\overline{MS}}^{n_f=3}=298 \pm 16$ MeV, which is equivalent to $α_s(μ=M_Z,n_f=5)=0.1159(12)$. For the charm and bottom quark masses in the $\overline{MS}$ scheme, we obtain: $m_c(μ=m_c,n_f=4)=1.265(10)$ GeV and $m_b(μ=m_b,n_f=5)=4.188(37)$ GeV.

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BibTeXRIS

P. Petreczky, J. H. Weber. 2019-09-09. Strong coupling constant and heavy quark masses in 2+1 flavor QCD. https://doi.org/10.1103/physrevd.100.034519

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