Related papers: The strong coupling from a nonperturbative determi…
The precise value of the strong coupling $\alpha_s(m_{Z})$ at the $Z$-boson mass $m_{Z}$ is essential for high-energy phenomenology and precision tests of quantum chromodynamics (QCD). We present the status of a program targeting a $\sim…
We compute a theoretically driven prediction for the hadronic contribution to the electromagnetic running coupling at the $Z$ scale using lattice QCD and state-of-the-art perturbative QCD. We…
The phase structure of lattice QCD with two flavors and Wilson fermions is studied analytically. At $\beta=0$ we obtain rigorous lower and upper bounds for the critical hopping parameter $k_c(0)$ from a convergent hopping parameter…
We present O(g^4) calculations of both planar and non-planar Wilson loops for various actions in the presence of sea quarks. In particular, the plaquette, the static potential and the static self energy are calculated to this order for…
We review our new strategy and current status towards a high precision computation of the Lambda parameter from three-flavour simulations in QCD. To reach this goal we combine specific advantages of the Schr\"odinger functional and gradient…
We revisit the standard procedure to match non-perturbative models to perturbative QCD, using experimental data. The strong coupling constant plays a central role in the QCD evolution of parton densities. We will extend this procedure with…
From an accurate determination of the inter-quark potential, one can study the running coupling constant for a range of $R$-values and hence estimate the scale $\Lambda_{\overline{\rm MS}}$. Detailed results are presented for $SU(3)$ pure…
We present an overview of the recent lattice determination of the QCD coupling $\alpha_s$ by the ALPHA Collaboration. The computation is based on the non-perturbative determination of the $\Lambda$-parameter of $N_{\rm f}=3$ QCD, and the…
An elegant and more precise formula for the 3-loop perturbative QCD coupling is discussed. It improves the common expression (e.g., canonized by PDG) in few GeV region. On its base, we propose simple analytic Model for ghost-free QCD…
We compare the perturbatively calculated QCD potential to that obtained from lattice calculations in the theory without light quark flavours. We examine E_tot(r) = 2 m_pole + V_QCD(r) by re-expressing it in the MSbar mass m =…
We calculate, to 3 loops in perturbation theory, the bare $\beta$-function of QCD, formulated on the lattice with the clover fermionic action. The dependence of our result on the number of colors $N$, the number of fermionic flavors $N_f$,…
Based on a study of the analytic running coupling obtained from the standard perturbation theory results up to four-loop order, the QCD ``synthetic'' running coupling \alpha_{syn} is built. In so doing the perturbative time-like…
We determine the value of the strong coupling $\alpha_\text{s}$ and study its running over a wide range of scales as probed by the dijet production process at hadron colliders, based on an NNLO QCD analysis of LHC dijet data. From a large…
We use lattice QCD simulations, with MILC gluon configurations and HISQ c-quark propagators, to make very precise determinations of moments of charm-quark pseudoscalar, vector and axial-vector correlators. These moments are combined with…
We analyze the pressure and density equations of state of unpolarized non-relativistic fermions at finite temperature in one spatial dimension. For attractively interacting regimes, we perform a third-order lattice perturbation theory…
We present preliminary results towards a fully non-perturbative determination of the equation of state of QCD at very high-temperatures, $T\approx 3-80\,{\rm GeV}$. The key ingredient is the lattice formulation of QCD in a moving reference…
We present an extensive study on the direct determination of the running coupling alpha_s from the static quark antiquark force at short distances, in quenched QCD. We find from our high statistics potential analysis that alpha_qq exhibits…
The strong coupling limit ($\beta_{gauge}=0$) of lattice QCD with staggered fermions enjoys the same non-perturbative properties as continuum QCD, namely confinement and chiral symmetry breaking. In contrast to the situation at weak…
We describe the first lattice determination of the strong coupling constant with 3 flavors of dynamical quarks. The method follows previous analyses in using a perturbative expansion for the plaquette and Upsilon spectroscopy to set the…
While lattice QCD allows for reliable results at small momentum transfers (large quark separations), perturbative QCD is restricted to large momentum transfers (small quark separations). The latter is determined up to a reference momentum…