Related papers: Strong coupling constant from vacuum polarization …
In this paper we compare recent experimental data for the total cross section $\sigma(e^+e^-\to{hadrons})$ with the up-to-date theoretical prediction of perturbative QCD for those energies where perturbation theory is reliable. The…
In the strong coupling limit, $n$-point functions in lattice QCD with staggered fermions can be rewritten exactly as sums over constrained configurations of monomers, dimers, and baryon loops covering the spacetime lattice. Worm algorithms…
We present a first attempt to experimentally extract an effective strong coupling constant that we define to be a low Q2 extension of a previous definition by S. Brodsky et al. following an initial work of G. Grunberg. Using Jefferson Lab…
Using recent CLEO III results for the cross section for $e^+e^- \to {\rm hadrons}$ at seven centre-of-mass energies between 6.964 and 10.538 GeV, we derive a value for the strong coupling constant…
We present a determination of the strong coupling constant using ATLAS inclusive jet cross section data at sqrt{s} = 7TeV, with their full information on the bin-to-bin correlations. Several procedures for combining the statistical…
QCD running coupling constant $\alpha_s(m_c)$ and $\alpha_s(m_b)$ are determined from heavy quarkonia $c\overline{c}$ and $b\overline{b}$ decays. The decay rates of $V\rightarrow 3g$ and $V\rightarrow e^+ e^-$ for $V=J/\psi$ and $\Upsilon$…
We perform pQCD analysis of the existing DIS data for charged leptons with account of corrections up to the NNLO. The parton distributions, value of strong coupling constant, and high-twist terms are extracted and their stability with…
The strong coupling limit of lattice QCD with staggered fermions has been studied for decades, both via Monte Carlo and via mean field theory. In this model, the finite density sign problem can be made mild and the full phase diagram can be…
We evaluate the $\Lambda_c\Sigma_c\pi$ coupling constant ($G_{\Lambda_c \Sigma_c \pi}$) and the width of the strong decay $\Sigma_c \rightarrow\Lambda_c \pi$ in 2+1 flavor lattice QCD on four different ensembles with pion masses ranging…
Decay constants of pseudoscalar mesons $D$, $D_s$, $\eta_c$ and vector mesons $D^*$, $D_s^*$, $J/\psi$ are determined from $N_f=2+1$ lattice QCD at a lattice spacing $a\sim0.08$ fm. For vector mesons, the decay constants defined by tensor…
We develop a strong-coupling ($t \ll U$) expansion technique for calculating the density profile for bosonic atoms trapped in an optical lattice with an overall harmonic trap at finite temperature and finite on site interaction in the…
Three-flavor QCD simulation with the $O(a)$-improved Wilson fermion action is made employing an exact fermion algorithm developed for odd number of quark flavors. For the plaquette gauge action, an unexpected first-order phase transition is…
The prospects for a determination of the strong coupling constant $\alpha_s$ via scaling violations of fragmentation functions in deeply inelastic scattering are studied. The statistical error in the case of an integrated luminosity of $250…
It is expected that the only effect of heavy dynamical fermions in QCD is to renormalize the gauge coupling. We derive a simple expression for the shift in the gauge coupling induced by $N_f$ flavors of heavy fermions. We compare this…
The recent determination of the $\beta$--function of the QCD running coupling $\alpha_{\overline{MS}}(Q^2)$ to 5-loops{\color{blue},} provides a verification of the convergence of a novel method for determining the fundamental QCD parameter…
In this article, the three point QCD sum rules is used to compute the strong coupling constants of vertices containing the strange bottomed ( charmed ) mesons with pion. The coupling constants are calculated, when both the bottom ( charm )…
We make a critical analysis on the free parameters of the Cornell potential $-4\alpha_{s}/3r+br+c$ and provide a parameterisation space for the strong coupling constant $\alpha_{s}$ and the constant shift $c$ for choosing linear part as…
The current world-average of the strong coupling at the Z pole mass, $\alpha_s(m^2_{Z}) = 0.1181 \pm 0.0013$, is obtained from a comparison of perturbative QCD calculations computed, at least, at next-to-next-to-leading-order accuracy, to a…
We report on our study of flavor-singlet mesons in three-flavor QCD with dynamical overlap quarks. Gauge ensembles are generated on a 16^3 x 48 lattice at a lattice spacing of 0.10 fm with the strange quark masses around its physical value…
In this research, the strong coupling constants of the $D^*D_s^*K$, $D_1D_{s1}K$, $D^*D_sK$ and $D_1D_{s0}^*K$ vertices are evaluated, using the three-point QCD sum rules. In order to calculate the coupling constant of each vertex, either…