Related papers: The Effective Fine Structure Constant at TESLA Ene…
To measure the strong coupling alpha_s from event shape observables two ingredients are necessary. A perturbative prediction containing the dependence of observables on alpha_s and a description of the hadronisation process to match the…
In this review we discuss the progress of the past decade in testing for a possible temporal variation of the fine structure constant $\alpha$. Advances in atomic sample preparation, laser spectroscopy and optical frequency measurements led…
A means to extract the fine-structure constant $\alpha$ from precision spectroscopic data on one-electron ions is presented. We show that in an appropriately weighted difference of the bound-electron $g$ factor and the ground state energy,…
A measurement of the effective leptonic weak mixing angle $\sin^2\theta_\mathrm{eff}^\ell$ is presented using the forward-backward asymmetry in Drell-Yan dilepton events produced in pp collisions at $\sqrt{s}=13$ TeV. The data sample…
We have determined the strong coupling alpha-s from a comprehensive study of energy-energy correlations (EEC) and their asymmetry (AEEC) in hadronic decays of Z0 bosons collected by the SLD experiment at SLAC. The data were compared with…
We report progress in our lattice study of hadronic weak matrix elements relevant for the Delta I = 1/2 rule and epsilon-prime. The presented results are from our first runs on a quenched ensemble with beta=6.0 and a dynamical Nf=2 ensemble…
We present the first high-twist study of the proton form factors $F_{1,2}(Q^2)$ in $ep$ elastic scattering based on the perturbative QCD $k_T$ factorization, $Q^2$ being momentum transfer squared. It is motivated by unexpectedly large…
A high precision determination of the strong coupling constant in the MS-bar scheme at the Z-mass scale, using low energy quantities, namely pion/kaon decay constants and masses, as experimental input is presented. The computation employs…
Using the CLEO detector at the Cornell Electron Storage Ring, we have made a measurement of R=sigma(e+e- ->hadrons)/sigma(e+e- ->mu+mu-) =3.56+/-0.01+/-0.07 at ECM=10.52 GeV. This implies a value for the strong coupling constant of…
We present the first determination of the strong coupling constant from the three-jet rate in e+e- annihilation at LEP, based on a next-to-next-to-leading order (NNLO) perturbative QCD prediction. More precisely, we extract alpha_s by…
We derive a factorization theorem for the structure-dependent QED effects in the weak exclusive process $B^-\to\ell^-\bar\nu_\ell$, i.e., effects probing the internal structure of the $B$ meson. The derivation requires a careful treatment…
State-resolved laser spectroscopy at the 10$^{-12}$ precision level recently reported in $arXiv$:2406.18719 determined the fractional change in nuclear quadrupole moment between the ground and isomeric state of $^{229}\rm{Th}$, $\Delta…
The C-parameter event-shape distribution for e+e- annihilation into hadrons is computed in the framework of SCET including input from fixed-order perturbation theory. We calculate all missing ingredients for achieving N3LL resummation…
We present a new extraction of the effective strong coupling constant \alpha_{s,g_1}(Q^2). The result agrees with a previous determination and extends the measurement of the low and high Q^2 behavior of \alpha_{s,g_1}(Q^2) that was…
Effective field theories provide a formalism for categorizing low-energy effects of a high-energy fundamental theory in terms of the low-energy degrees of freedom. This process has been well established in mapping the fundamental theory of…
We study infrared contributions to the QCD description of the HERA data on the structure function $F_{2}$ within the \textit{generalized} DAS approximation. We argue that this approximation is a natural one and consistent with the…
We introduce a methodology to test models with spatial variations of the fine-structure constant $\alpha$, based on the calculation of the angular power spectrum of these measurements. This methodology enables comparisons of observations…
Charged particle production in deep-inelastic ep scattering is measured with the H1 detector at HERA. The kinematic range of the analysis covers low photon virtualities, 5 < Q^2 < 100 GeV^2, and small values of Bjorken-x, 10^{-4} < x <…
An NLO QCD analysis on the HERA combined cross sections obtained from the measurements using the data up to the year 2000 at both the H1 and ZEUS collaborations provides significantly improved parton distribution functions. In 2007, HERA…
Multi-hadronic events produced in e+e- collisions provide an excellent laboratory to study QCD, the theory of strong interactions, and in particular to determine the strong coupling parameter alpha_s and demonstrate its predicted behavior…