Related papers: QCD and Hadronic Interactions with Initial-State-R…
The KLOE experiment at the DA$\Phi$NE $\phi$-factory has performed a new precise measurement of the pion form factor using Initial State Radiation events. Results based on an integrated luminosity of 240 pb$^{-1}$ and extraction of the…
We compute the vacuum polarisation on the lattice in quenched QCD using non-perturbatively improved Wilson fermions. Above Q^2 of about 2 GeV^2 the results are very close to the predictions of perturbative QCD. Below this scale we see signs…
We construct a physically motivated model for the isospin-one non-strange vacuum polarization function Pi(Q^2) based on a spectral function given by vector-channel OPAL data from hadronic tau decays for energies below the tau mass and a…
We present a progress report on the calculation of the connected hadronic contribution to the muon g-2 with C* boundary conditions. For that purpose we use a QCD gauge ensemble with 3+1 flavors and two QCD+QED gauge ensembles with 1+2+1…
In order to reduce the current hadronic uncertainties in the theory prediction for the anomalous magnetic moment of the muon, lattice calculations need to reach sub-percent accuracy on the hadronic-vacuum-polarization contribution. This…
The hadronic vacuum polarization contribution to the anomalous magnetic moment of a lepton is considered as a function of the lepton mass. We show how the analyticity properties of this function allow for its full reconstruction when it is…
In this paper, we discuss how windows in Euclidean time can be used to isolate the origin of potential conflicts between evaluations of the hadronic-vacuum-polarization (HVP) contribution to the anomalous magnetic moment of the muon in…
We discuss the prospects for improving the precision on the hadronic corrections to the anomalous magnetic moment of the muon, and the plans of the Muon $g-2$ Theory Initiative to update the Standard Model prediction.
The experimental value of g-2 of the muon is larger by $4.2 \sigma$ than the Standard Model prediction based on the hadronic vacuum polarization contribution (HVP) determined from the measured R-ratio, $\sigma(e^+e^- \! \rightarrow \!…
The dispersive approaches to the hadronic vacuum polarisation contributions to the muon anomalous magnetic moment $a_\mu$ are described. The main issues are discussed followed by perspectives in the next years.
We report the first result for the hadronic light-by-light scattering contribution to the muon anomalous magnetic moment with all errors systematically controlled. Several ensembles using 2+1 flavors of physical mass M\"obius domain-wall…
The electromagnetic interactions of electrons and muons can be described to very high accuracy within the framework of standard theory, in particular within the hydrogen-like muonium atom. Therefore precision measurements allow to test…
We present our lattice QCD result for the long-distance part of the hadronic vacuum polarization contribution, $(a_\mu^{\rm hvp})^{\rm LD}$, to the muon $g-2$ in the time-momentum representation. This is the numerically dominant, and at the…
We discuss hadronic effects in the muonium hyperfine structure and derive an expression for the hadronic contribution to the hfs interval in form of the one-dimensional integral of the cross section of e+e- annihilation into hadrons.…
The well-known problem of the unknown power corrections within QCD improved factorisation leaves the interpretation of the so-called LHCb anomalies in the angular observables of B-->K* mu+ mu- as an open problem. In order to contribute to…
The ISR method has been largely exploited by the BABAR experiment, for measuring numerous channels of the cross section e+e- into hadrons. For the pi+pi-(gamma) and K+K-(gamma) channels, BABAR has pioneered the method based on the ratio…
We investigate hadroproduction of $B_c$ mesons from initial gluons using QCD perturbation theory and nonrelativistic bound state approximations. Our results obtained by two completely independent calculations are confronted with existing…
We have performed a new evaluation of the hadronic contribution to $a_{\mu}=(g-2)/2$ of the muon with explicit correlations of systematic errors among the experimental data on $\sigma( e^+e^- \to hadrons )$. Our result for the lowest order…
The MUonE experiment aims at providing a new independent evaluation of the leading hadronic contribution to the muon anomalous magnetic moment. The proposed method is based on the measurement of the running of the QED coupling in the…
Hadronic vacuum polarization (HVP) is not only a critical part of the Standard Model (SM) prediction for the anomalous magnetic moment of the muon $(g-2)_\mu$, but also a crucial ingredient for global fits to electroweak (EW) precision…